Fix EXIF viewer breaking on binary MakerNote fields

Pentax and other cameras have binary EXIF fields (MakerNote, etc.) that
contain raw bytes. The previous code used errors="replace" which still
produced strings with replacement characters that broke JSON parsing.

Now properly detect non-printable binary data and display as
"<N bytes binary>" instead.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.dockerignore

@@ -25,7 +25,6 @@ rpi/
 *.img.xz
 *.img.zst
 *.img.zst.zip
-pishrink.sh
 
 # Docs
 *.md

.gitignore

@@ -64,11 +64,16 @@ htmlcov/
 # Output test files.
 test_data/*.png
 
-# Dev scripts (local convenience scripts - except validate-release.sh)
+# Dev scripts (local convenience scripts - except these)
 scripts/*
 !scripts/validate-release.sh
+!scripts/smoke-test.sh
+!scripts/setup-trusted-certs.sh
+!scripts/screenshots.sh
+!scripts/build.sh
 
 # Web UI auth database and SSL certs
+instance/
 frontends/web/instance/
 frontends/web/certs/
 
@@ -79,17 +84,21 @@ tests/
 *.img
 *.img.xz
 *.img.zst
-pishrink.sh
 *.img.zst.zip
+rpi/tools/pishrink.sh
 
 # Temp file storage
 frontends/web/temp_files/
 rpi/config.json
 
 # Pre-built Pi tarballs and images (release assets, too large for git)
-rpi/stegasoo-pi-arm64.tar.zst
-rpi/stegasoo-pi-arm64.tar.zst.zip
-rpi/stegasoo-venv-pi-arm64.tar.zst
+rpi/*.tar.zst
+rpi/*.tar.zst.zip
 rpi/*.img
 rpi/*.img.zst
 rpi/*.img.zst.zip
+
+# AUR build artifacts
+aur-upload/
+aur/.SRCINFO
+aur/*.pkg.tar.zst

API.md

@@ -88,7 +88,7 @@ uvicorn main:app --host 0.0.0.0 --port 8000 --workers 4
 
 **Docker with channel key:**
 ```bash
-STEGASOO_CHANNEL_KEY=XXXX-XXXX-... docker-compose up api
+STEGASOO_CHANNEL_KEY=XXXX-XXXX-... docker-compose -f docker/docker-compose.yml up api
 ```
 
 ---
@@ -843,7 +843,7 @@ curl -s -X POST "$BASE_URL/decode/multipart" \
 
 ## Docker Configuration
 
-### docker-compose.yml
+### docker/docker-compose.yml
 
 ```yaml
 x-common-env: &common-env

CHANGELOG.md

@@ -5,6 +5,27 @@ All notable changes to Stegasoo will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org).
 
+## [4.1.5] - 2026-01-07
+
+### Added
+- **Developer Documentation**: Educational comments throughout core modules
+  - DCT module: zig-zag diagrams, QIM explanation, Reed-Solomon deep dive
+  - LSB module: visual bit embedding examples, ChaCha20 pixel selection
+  - Crypto module: multi-factor KDF flow diagrams, Argon2id reasoning
+  - CLI module: Click patterns (groups, JSON output, secure input)
+  - Web UI module: Flask architecture, subprocess isolation, async jobs
+- **Pi Test Automation**: `rpi/kickoff-pi-test.sh` script
+  - One command to flash, wait for boot, setup, and smoke test
+  - Self-contained (no dotfile dependencies)
+- **v4.2 Wishlist**: `WISHLIST-4.2.md` for blue-sky ideas (GPU acceleration)
+
+### Changed
+- **Pi MOTD Improvements**:
+  - Dynamic temperature emoji (ice/cool/fire based on temp)
+  - Rocket emoji for service status, globe emoji for URL
+  - Shortened Debian boilerplate message
+  - Fixed escaped variable syntax in heredoc
+
 ## [4.1.3] - 2026-01-05
 
 ### Added
@@ -180,6 +201,7 @@ and this project adheres to [Semantic Versioning](https://semver.org).
 - CLI interface
 - Basic PIN authentication
 
+[4.1.5]: https://github.com/adlee-was-taken/stegasoo/compare/v4.1.3...v4.1.5
 [4.1.3]: https://github.com/adlee-was-taken/stegasoo/compare/v4.1.0...v4.1.3
 [4.1.0]: https://github.com/adlee-was-taken/stegasoo/compare/v4.0.2...v4.1.0
 [4.0.2]: https://github.com/adlee-was-taken/stegasoo/compare/v4.0.1...v4.0.2

CLI.md

@@ -64,6 +64,18 @@ python -c "from stegasoo import has_dct_support; print('DCT:', 'available' if ha
 stegasoo channel show
 ```
 
+### Man Page
+
+```bash
+# Install man page
+sudo mkdir -p /usr/local/share/man/man1
+sudo cp docs/stegasoo.1 /usr/local/share/man/man1/
+sudo mandb
+
+# View
+man stegasoo
+```
+
 ---
 
 ## What's New in v4.1.0
@@ -152,7 +164,7 @@ stegasoo generate [OPTIONS]
 | `--pin/--no-pin` | | flag | `--pin` | Generate a PIN |
 | `--rsa/--no-rsa` | | flag | `--no-rsa` | Generate an RSA key |
 | `--pin-length` | | 6-9 | 6 | PIN length in digits |
-| `--rsa-bits` | | choice | 2048 | RSA key size (2048, 3072, 4096) |
+| `--rsa-bits` | | choice | 2048 | RSA key size (2048, 3072) |
 | `--words` | | 3-12 | 4 | Words in passphrase |
 | `--output` | `-o` | path | | Save RSA key to file |
 | `--password` | `-p` | string | | Password for RSA key file |
@@ -168,7 +180,7 @@ stegasoo generate
 stegasoo generate --words 6
 
 # Generate with RSA key
-stegasoo generate --rsa --rsa-bits 4096
+stegasoo generate --rsa --rsa-bits 3072
 
 # Save RSA key to encrypted file
 stegasoo generate --rsa -o mykey.pem -p "mysecretpassword"
@@ -798,7 +810,7 @@ stegasoo decode -r ref.jpg -s stego.png -p "phrase" --pin 123456
 
 ### Docker Deployment
 
-**docker-compose.yml:**
+**docker/docker-compose.yml:**
 ```yaml
 x-common-env: &common-env
   STEGASOO_CHANNEL_KEY: ${STEGASOO_CHANNEL_KEY:-}

DOCKER.md

@@ -6,14 +6,14 @@ Stegasoo provides Docker images for both the Web UI and REST API.
 
 ```bash
 # Build and start all services
-docker-compose up -d
+docker-compose -f docker/docker-compose.yml up -d
 
 # Check status
-docker-compose ps
+docker-compose -f docker/docker-compose.yml ps
 ```
 
 Access:
-- **Web UI**: http://localhost:5000
+- **Web UI**: https://localhost:5000 (HTTPS with self-signed cert)
 - **REST API**: http://localhost:8000
 
 ## Services
@@ -36,9 +36,12 @@ STEGASOO_CHANNEL_KEY=XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX
 # Web UI authentication (default: enabled)
 STEGASOO_AUTH_ENABLED=true
 
-# HTTPS support (default: disabled)
-STEGASOO_HTTPS_ENABLED=false
+# HTTPS support (default: enabled, generates self-signed cert)
+STEGASOO_HTTPS_ENABLED=true
 STEGASOO_HOSTNAME=localhost
+
+# To disable HTTPS:
+# STEGASOO_HTTPS_ENABLED=false
 ```
 
 ### Volume Mounts
@@ -58,10 +61,10 @@ Uses a pre-built base image with all dependencies:
 
 ```bash
 # First time only: build the base image
-docker build -f Dockerfile.base -t stegasoo-base:latest .
+docker build -f docker/Dockerfile.base -t stegasoo-base:latest .
 
 # Build services (fast - only copies app code)
-docker-compose build
+docker-compose -f docker/docker-compose.yml build
 ```
 
 ### Full Build (No Base Image)
@@ -69,26 +72,26 @@ docker-compose build
 If you don't have the base image, the Dockerfile will build all dependencies (slower):
 
 ```bash
-docker-compose build
+docker-compose -f docker/docker-compose.yml build
 ```
 
 ## Commands
 
 ```bash
 # Start services
-docker-compose up -d
+docker-compose -f docker/docker-compose.yml up -d
 
 # View logs
-docker-compose logs -f
+docker-compose -f docker/docker-compose.yml logs -f
 
 # Stop services
-docker-compose down
+docker-compose -f docker/docker-compose.yml down
 
 # Rebuild after code changes
-docker-compose build && docker-compose up -d
+docker-compose -f docker/docker-compose.yml build && docker-compose -f docker/docker-compose.yml up -d
 
 # Full rebuild (no cache)
-docker-compose build --no-cache
+docker-compose -f docker/docker-compose.yml build --no-cache
 ```
 
 ## Resource Limits
@@ -109,7 +112,7 @@ Both services include health checks:
 
 Check health status:
 ```bash
-docker-compose ps
+docker-compose -f docker/docker-compose.yml ps
 ```
 
 ## Production Deployment
@@ -126,7 +129,7 @@ For production, consider:
    ```bash
    # Don't commit .env files with secrets
    export STEGASOO_CHANNEL_KEY=your-key
-   docker-compose up -d
+   docker-compose -f docker/docker-compose.yml up -d
    ```
 
 3. **Reverse proxy**: Put behind nginx/traefik for TLS termination
@@ -142,12 +145,12 @@ For production, consider:
 ### Container won't start
 ```bash
 # Check logs
-docker-compose logs web
-docker-compose logs api
+docker-compose -f docker/docker-compose.yml logs web
+docker-compose -f docker/docker-compose.yml logs api
 ```
 
 ### Out of memory
-Increase Docker's memory allocation or reduce worker count in Dockerfile.
+Increase Docker's memory allocation or reduce worker count in `docker/Dockerfile`.
 
 ### Permission errors
 The containers run as non-root user `stego` (UID 1000). Ensure volume permissions match.

INSTALL.md

@@ -154,10 +154,10 @@ Build and run individual containers.
 #### Build Images
 
 ```bash
-# Build all targets
-docker build -t stegasoo-web --target web .
-docker build -t stegasoo-api --target api .
-docker build -t stegasoo-cli --target cli .
+# From project root - build all targets
+docker build -t stegasoo-web --target web -f docker/Dockerfile .
+docker build -t stegasoo-api --target api -f docker/Dockerfile .
+docker build -t stegasoo-cli --target cli -f docker/Dockerfile .
 ```
 
 #### Run Web UI
@@ -214,17 +214,17 @@ The easiest way to run all services.
 
 ```bash
 # Start in background
-docker-compose up -d
+docker-compose -f docker/docker-compose.yml up -d
 
 # Start specific service
-docker-compose up -d web
-docker-compose up -d api
+docker-compose -f docker/docker-compose.yml up -d web
+docker-compose -f docker/docker-compose.yml up -d api
 
 # View logs
-docker-compose logs -f
+docker-compose -f docker/docker-compose.yml logs -f
 
 # Stop all
-docker-compose down
+docker-compose -f docker/docker-compose.yml down
 ```
 
 #### Authentication Configuration (v4.0.2)
@@ -239,7 +239,7 @@ STEGASOO_HOSTNAME=localhost     # Hostname for SSL cert
 STEGASOO_CHANNEL_KEY=           # Optional channel key
 
 # Then run
-docker-compose up -d web
+docker-compose -f docker/docker-compose.yml up -d web
 ```
 
 On first access, you'll be prompted to create an admin account. The database and SSL certs are persisted in Docker volumes.
@@ -255,16 +255,16 @@ On first access, you'll be prompted to create an admin account. The database and
 
 ```bash
 # Build images and start
-docker-compose up -d --build
+docker-compose -f docker/docker-compose.yml up -d --build
 
 # Force rebuild (no cache)
-docker-compose build --no-cache
-docker-compose up -d
+docker-compose -f docker/docker-compose.yml build --no-cache
+docker-compose -f docker/docker-compose.yml up -d
 ```
 
 #### Resource Configuration
 
-The `docker-compose.yml` includes resource limits:
+The `docker/docker-compose.yml` includes resource limits:
 
 ```yaml
 services:
@@ -852,7 +852,7 @@ Argon2 needs 256MB per operation. Increase container memory:
 # Docker run
 docker run --memory=768m ...
 
-# Docker Compose - edit docker-compose.yml
+# Docker Compose - edit docker/docker-compose.yml
 deploy:
   resources:
     limits:

PLAN-4.1.0.md

@@ -1,538 +0,0 @@
-# Stegasoo 4.1.0 Plan
-
-## Overview
-
-Version 4.1.0 is a feature release focusing on small-group deployment improvements and new utilities.
-
-## Goals
-
-1. ~~**Multi-User Support** - Admin can create up to 16 users for shared deployments~~ ✅ DONE
-2. **Channel Key QR** - Easy visual sharing of channel keys via QR codes
-3. ~~**CLI Channel Commands** - Manage channel keys from command line~~ ✅ DONE
-4. **Advanced Tools** - Image/stego utilities (TBD)
-
----
-
-## Feature 1: Multi-User Support ✅ COMPLETED
-
-> Implemented in commit 7b33501. All requirements met.
-
-### Requirements
-
-- 16 users + 1 admin maximum (17 total)
-- First user created at setup is always admin
-- Admin can add/delete users, reset passwords
-- Regular users can only change their own password
-- No self-registration (admin-invite only)
-
-### Database Changes
-
-**Update User model in `frontends/web/models.py`:**
-
-```python
-class User(db.Model):
-    id = Column(Integer, primary_key=True)
-    username = Column(String(80), unique=True, nullable=False)
-    password_hash = Column(String(255), nullable=False)
-    role = Column(String(20), default='user')  # 'admin' or 'user'
-    created_at = Column(DateTime, default=datetime.utcnow)
-```
-
-**Migration:** Add `role` and `created_at` columns. Existing users get `role='admin'`.
-
-### New Routes
-
-| Route | Method | Access | Description |
-|-------|--------|--------|-------------|
-| `/admin/users` | GET | admin | List all users |
-| `/admin/users/new` | GET, POST | admin | Create user form |
-| `/admin/users/<id>/delete` | POST | admin | Delete user |
-| `/admin/users/<id>/reset-password` | POST | admin | Generate temp password |
-
-### New Decorator
-
-```python
-# auth.py
-def admin_required(f):
-    @wraps(f)
-    def decorated(*args, **kwargs):
-        if not current_user.is_authenticated:
-            return redirect(url_for('login'))
-        if current_user.role != 'admin':
-            flash('Admin access required', 'error')
-            return redirect(url_for('index'))
-        return f(*args, **kwargs)
-    return decorated
-```
-
-### UI Changes
-
-**Navigation (for admin users):**
-- Add "Users" link in navbar (visible only to admin)
-
-**Account page (`/account`):**
-- Admin sees link to user management
-- All users see their own password change form
-
-**New template: `templates/admin/users.html`:**
-- Table: Username | Role | Created | Actions
-- Actions: Reset Password, Delete (disabled for self)
-- "Add User" button (disabled if at 16 user limit)
-- Show count: "3 of 16 users"
-
-**New template: `templates/admin/user_new.html`:**
-- Username field (email-style allowed)
-- Password field (auto-populated with random 8-char, admin can override)
-- Submit → confirmation page shows password once with copy button
-
-### Validation
-
-- Username: 3-80 chars, alphanumeric + underscore/hyphen + @/. for email-style
-- Password: 8+ chars (same as current)
-- Can't delete yourself
-- Can't demote the last admin
-- Deleting user immediately invalidates their sessions
-
----
-
-## Feature 2: Channel Key QR
-
-### Web UI
-
-**About page additions:**
-
-If `STEGASOO_CHANNEL_KEY` environment variable is set:
-
-```
-┌─────────────────────────────────────────┐
-│  Channel Key                            │
-│                                         │
-│  ██████████████    Your server uses a   │
-│  ██          ██    private channel key. │
-│  ██  ██████  ██    Share this QR with   │
-│  ██  ██████  ██    others to join.      │
-│  ██          ██                         │
-│  ██████████████    [Copy Key] [Download]│
-│                                         │
-│  Key: abc123...xyz                      │
-└─────────────────────────────────────────┘
-```
-
-- QR generated server-side using `qrcode` library
-- "Copy Key" copies text to clipboard
-- "Download QR" saves as PNG
-
-**Implementation:**
-
-```python
-# about route addition
-@app.route('/about')
-def about():
-    channel_key = os.environ.get('STEGASOO_CHANNEL_KEY', '')
-    channel_qr_b64 = None
-    if channel_key:
-        # Generate QR as base64 PNG
-        qr = qrcode.make(channel_key)
-        buffer = BytesIO()
-        qr.save(buffer, format='PNG')
-        channel_qr_b64 = base64.b64encode(buffer.getvalue()).decode()
-    return render_template('about.html',
-                          channel_key=channel_key,
-                          channel_qr=channel_qr_b64)
-```
-
-### CLI Commands
-
-**New command group: `stegasoo channel`**
-
-```bash
-# Generate a new channel key
-stegasoo channel generate
-# Output:
-# Channel Key: stg_abc123...xyz789
-#
-# ██████████████████
-# ██              ██
-# ██  ██████████  ██
-# ...
-#
-# Set in environment: export STEGASOO_CHANNEL_KEY="stg_abc123..."
-
-# Show current key (from env or argument)
-stegasoo channel show
-# Output:
-# Channel Key: stg_abc123...xyz789
-
-# Display QR in terminal (ASCII)
-stegasoo channel qr
-# Output: ASCII QR code
-
-# Save QR as PNG
-stegasoo channel qr -o channel-key.png
-# Output: Saved to channel-key.png
-
-# Explicit format selection
-stegasoo channel qr --format ascii      # Terminal (default)
-stegasoo channel qr --format png -o -   # PNG to stdout
-```
-
-**Implementation notes:**
-
-- Use `qrcode[pil]` for PNG output
-- Use `qrcode` with `print_ascii()` for terminal
-- Read key from `--key` argument or `STEGASOO_CHANNEL_KEY` env var
-- `generate` uses existing `generate_channel_key()` from `stegasoo.channel`
-
----
-
-## File Changes Summary
-
-### New Files
-
-| File | Description |
-|------|-------------|
-| `frontends/web/templates/admin/users.html` | User management page |
-| `frontends/web/templates/admin/user_new.html` | Add user form |
-
-### Modified Files
-
-| File | Changes |
-|------|---------|
-| `frontends/web/models.py` | Add `role`, `created_at` to User |
-| `frontends/web/auth.py` | Add `@admin_required`, user management routes |
-| `frontends/web/templates/base.html` | Add Users link for admins |
-| `frontends/web/templates/account.html` | Add admin link |
-| `frontends/web/templates/about.html` | Add channel key QR section |
-| `src/stegasoo/cli.py` | Add `channel` command group |
-
----
-
-## Testing Plan
-
-### Multi-User
-
-1. Fresh install → first user is admin
-2. Admin can create users up to limit (16)
-3. Admin can't create 17th user (shows error)
-4. Regular user can log in, encode/decode
-5. Regular user can't access `/admin/users`
-6. Admin can reset user password
-7. Admin can delete user
-8. Admin can't delete self
-9. Existing 4.0.2 databases upgrade correctly (single user becomes admin)
-
-### Channel Key QR
-
-1. About page shows nothing if no channel key
-2. About page shows QR + key if channel key set
-3. Copy button works
-4. Download gives valid PNG
-5. QR scans correctly to key value
-
-### CLI
-
-1. `channel generate` creates valid key + shows QR
-2. `channel show` displays current key
-3. `channel qr` outputs ASCII to terminal
-4. `channel qr -o file.png` saves PNG
-5. Commands work with `--key` override
-6. Commands read from env var
-
----
-
-## Feature 3: Advanced Tools
-
-### Included Tools
-
-| Tool | Web | CLI | Description |
-|------|-----|-----|-------------|
-| **Capacity Calculator** | ✓ | ✓ | Upload image → show DCT/LSB capacity |
-| **Metadata Stripper** | ✓ | ✓ | Remove EXIF/metadata from image |
-| **Stego Detector** | ✓ | ✓ | Analyze image for signs of hidden data |
-| **Image Compare** | ✓ | - | Side-by-side before/after diff |
-| **Header Peek** | ✓ | ✓ | Check for Stegasoo header without decrypting |
-| **Batch Mode** | - | ✓ | Encode/decode multiple files |
-
-### Web UI: `/tools` Page
-
-New page with card-based layout:
-
-```
-┌─────────────────────────────────────────────────────────────┐
-│  🛠️ Advanced Tools                                          │
-├─────────────────────────────────────────────────────────────┤
-│                                                             │
-│  ┌─────────────────┐  ┌─────────────────┐                   │
-│  │ 📏 Capacity     │  │ 🧹 Metadata     │                   │
-│  │   Calculator    │  │   Stripper      │                   │
-│  │                 │  │                 │                   │
-│  │ Check how much  │  │ Remove EXIF     │                   │
-│  │ data fits       │  │ before encoding │                   │
-│  └─────────────────┘  └─────────────────┘                   │
-│                                                             │
-│  ┌─────────────────┐  ┌─────────────────┐                   │
-│  │ 🔍 Stego        │  │ 🔎 Header       │                   │
-│  │   Detector      │  │   Peek          │                   │
-│  │                 │  │                 │                   │
-│  │ Analyze image   │  │ Check for       │                   │
-│  │ for hidden data │  │ Stegasoo data   │                   │
-│  └─────────────────┘  └─────────────────┘                   │
-│                                                             │
-│  ┌─────────────────┐                                        │
-│  │ ⚖️ Image        │                                        │
-│  │   Compare       │                                        │
-│  │                 │                                        │
-│  │ Before/after    │                                        │
-│  │ diff view       │                                        │
-│  └─────────────────┘                                        │
-│                                                             │
-└─────────────────────────────────────────────────────────────┘
-```
-
-Each card opens a modal or expands inline for the tool interface.
-
-### CLI Structure
-
-```bash
-# Capacity calculator
-stegasoo capacity image.jpg
-stegasoo capacity image.jpg --format json
-
-# Metadata stripper
-stegasoo strip image.jpg                    # Output to image_stripped.jpg
-stegasoo strip image.jpg -o clean.jpg       # Custom output
-stegasoo strip image.jpg --in-place         # Overwrite original
-
-# Stego detector
-stegasoo detect image.jpg
-stegasoo detect image.jpg --verbose         # Detailed analysis
-
-# Header peek
-stegasoo peek image.jpg
-# Output: "Stegasoo DCT header detected" or "No Stegasoo header found"
-
-# Batch mode
-stegasoo encode --batch manifest.json       # JSON with files + credentials
-stegasoo decode --batch input_dir/ --out output_dir/
-```
-
-### Tool Details
-
-#### Capacity Calculator
-- Input: Image file
-- Output: Dimensions, megapixels, DCT capacity, LSB capacity
-- Web: Upload zone + results panel
-- CLI: Table or JSON output
-
-#### Metadata Stripper
-- Input: Image file
-- Output: Clean image (EXIF/metadata removed)
-- Show what was removed (camera model, GPS, etc.)
-- Preserve image quality
-
-#### Stego Detector
-- Input: Image file
-- Analysis:
-  - Chi-square analysis (LSB detection)
-  - DCT coefficient histogram analysis
-  - Visual inspection hints
-- Output: Likelihood score + findings
-- Note: Detection is probabilistic, not definitive
-
-#### Image Compare
-- Input: Two images (original + stego)
-- Output:
-  - Side-by-side view
-  - Difference overlay (amplified)
-  - Pixel-level stats (PSNR, SSIM)
-- Web only (visual tool)
-
-#### Header Peek
-- Input: Image file
-- Output: Header found (yes/no), mode (DCT/LSB), embedded size estimate
-- Does NOT decrypt - just checks for valid header structure
-- Useful for "is this a stego image?" without credentials
-
-#### Batch Mode
-- CLI only
-- Manifest file (JSON) or directory-based
-- Progress bar for multiple files
-- Error handling per-file (continue on failure)
-
----
-
-## Migration Notes
-
-### Database Migration
-
-For existing 4.0.2 installations:
-
-```python
-# migrations/add_user_role.py
-def upgrade():
-    # Add columns with defaults
-    op.add_column('user', sa.Column('role', sa.String(20), default='user'))
-    op.add_column('user', sa.Column('created_at', sa.DateTime))
-
-    # Set existing users as admin (they were the first user)
-    op.execute("UPDATE user SET role = 'admin' WHERE role IS NULL")
-    op.execute("UPDATE user SET created_at = datetime('now') WHERE created_at IS NULL")
-```
-
-Or simpler: detect on startup, update schema automatically (current pattern).
-
----
-
-## Out of Scope
-
-- Per-user channel keys
-- User groups/teams
-- API authentication tokens
-- User activity logging
-- Password complexity rules beyond length
-
----
-
-## Estimated Effort
-
-| Component | Complexity |
-|-----------|------------|
-| Database schema change | Low |
-| Admin routes + templates | Medium |
-| Access control decorator | Low |
-| About page QR | Low |
-| CLI channel commands | Medium |
-| Advanced Tools (TBD) | Medium-High |
-| Testing | Medium |
-
----
-
-## Decisions
-
-1. **Temp password flow:** Password field auto-populates with random 8-char password. Admin can override if desired. Show password once on confirmation page.
-
-2. **Session handling:** Yes - deleting a user immediately invalidates their active sessions (ban hammer).
-
-3. **Username rules:** Sane requirements, email-style allowed. Validation: 3-80 chars, alphanumeric, underscore, hyphen, @ and . for email-style.
-
----
-
-## Approval
-
-- [x] Plan reviewed
-- [x] Questions resolved
-- [x] Ready to implement
-
-## Progress
-
-- [x] Multi-User Support (commit 7b33501)
-- [x] Channel Key QR (Web UI) - added QR generator on About page
-- [x] CLI Channel Commands
-- [x] Saved Channel Keys (Web UI) - users can save/manage channel keys
-- [x] Advanced Tools - Image Security Toolkit
-  - [x] CLI: `stegasoo tools capacity/strip/peek/exif`
-  - [x] API: `/api/tools/capacity`, `/api/tools/peek`, `/api/tools/exif/*`
-  - [x] WebUI: Tools page with tabbed interface
-  - [x] EXIF Editor with inline editing, clear all, save/download
-
----
-
-## Architectural Improvements (4.1.0)
-
-### Consolidated Channel Key Resolution
-
-Moved `resolve_channel_key()` from 3 duplicate implementations to single source of truth in `src/stegasoo/channel.py`:
-
-```python
-# Library: src/stegasoo/channel.py
-def resolve_channel_key(value, *, file_path=None, no_channel=False) -> str | None:
-    """Unified channel key resolution - returns None (auto), "" (public), or key."""
-
-def get_channel_response_info(channel_key) -> dict:
-    """Get channel info dict for API/WebUI responses."""
-```
-
-Frontends now use thin wrappers that translate exceptions to their context (Click/HTTP).
-
-### DCT Payload Pre-Check
-
-Added `will_fit_by_mode()` pre-check to WebUI encode to fail fast with helpful error message instead of cryptic exception deep in DCT processing.
-
-### EXIF Tools (Library Layer)
-
-Added to `src/stegasoo/utils.py`:
-- `read_image_exif(image_data)` - Read EXIF metadata as dict
-- `write_image_exif(image_data, updates)` - Update EXIF fields (JPEG only)
-
-Dependencies added: `piexif>=1.1.0`
-
----
-
-## Action Item: Architectural Review ✅ DONE
-
-Reviewed modules for consistency with Library → CLI → API → WebUI pattern:
-
-| Module | Library | CLI | API | WebUI | Status |
-|--------|---------|-----|-----|-------|--------|
-| encode | ✓ | ✓ | ✓ | ✓ | Consistent |
-| decode | ✓ | ✓ | ✓ | ✓ | Consistent |
-| channel | ✓ | ✓ | ✓ | ✓ | Consolidated resolve_channel_key |
-| tools | ✓ | ✓ | ✓ | ✓ | Complete |
-| generate | ✓ | ✓ | - | ✓ | CLI has `stegasoo generate` |
-
-Priority order: Developer/CLI → API integrator → WebUI end-user
-
----
-
-## Admin Recovery System (4.1.0) ✅ DONE
-
-Password reset capability for locked-out admins with multiple backup options.
-
-### Library Layer (`src/stegasoo/recovery.py`)
-
-```python
-# Key generation and validation
-generate_recovery_key() -> str       # XXXX-XXXX-XXXX-... (32 chars)
-hash_recovery_key(key) -> str        # SHA-256 for storage
-verify_recovery_key(key, hash) -> bool
-
-# QR code (obfuscated - scans as gibberish)
-obfuscate_key(key) -> str            # XOR with RECOVERY_OBFUSCATION_KEY
-deobfuscate_key(data) -> str | None
-generate_recovery_qr(key) -> bytes   # PNG with obfuscated data
-extract_key_from_qr(image) -> str | None
-
-# Stego backup (hide key in an image)
-create_stego_backup(key, carrier_image) -> bytes
-extract_stego_backup(stego_image, reference) -> str | None
-```
-
-### Database (`app_settings` table)
-
-- `recovery_key_hash` - SHA-256 of recovery key (or null if disabled)
-
-### Web Routes
-
-| Route | Method | Description |
-|-------|--------|-------------|
-| `/setup/recovery` | GET, POST | Step 2 of initial setup |
-| `/recover` | GET, POST | Password reset page |
-| `/recover/stego` | POST | Extract key from stego backup |
-| `/account/recovery/regenerate` | GET, POST | Generate new key |
-| `/account/recovery/disable` | POST | Remove recovery option |
-| `/account/recovery/stego-backup` | POST | Create stego backup |
-
-### CLI Commands
-
-```bash
-stegasoo admin recover --db path/to/stegasoo.db  # Reset password
-stegasoo admin generate-key [--qr]               # Generate key (reference)
-```
-
-### Security Model
-
-1. Recovery key shown once during setup - only hash stored
-2. QR codes XOR'd with `RECOVERY_OBFUSCATION_KEY` (fixed in constants.py)
-3. Stego backups use fixed internal passphrase/PIN - security is obscurity
-4. Instance-bound: recovery key hash must match in target database
-5. Options: text file, QR image, stego image, or no recovery (most secure)

PLAN-4.1.2.md

@@ -1,250 +0,0 @@
-# Stegasoo 4.1.2 Plan
-
-## Release Theme
-Polish and UX improvements after the 4.1.1 stability release.
-
----
-
-## 1. Real Progress Bar for Encode/Decode
-
-**Status:** Done
-
-**Problem:** Users see elapsed time but no indication of how far along the operation is. Long DCT encodes on Pi can take 2-3 minutes with no feedback.
-
-**Solution:** Polling + progress file approach
-
-### Backend Changes
-
-1. **dct_steganography.py** - Write progress during block loop:
-   ```python
-   if progress_file and block_num % 50 == 0:
-       with open(progress_file, 'w') as f:
-           json.dump({"current": block_num, "total": total_blocks, "phase": "embedding"}, f)
-   ```
-
-2. **app.py** - New endpoints:
-   - `POST /encode` returns `job_id`, starts subprocess
-   - `GET /encode/progress/<job_id>` returns progress JSON
-   - `GET /encode/result/<job_id>` returns final result when done
-
-3. **Subprocess wrapper** - Pass progress file path to encode/decode functions
-
-### Frontend Changes
-
-1. **stegasoo.js** - After form submit:
-   - Show progress bar (Bootstrap progress component)
-   - Poll `/encode/progress/{job_id}` every 500ms
-   - Update bar width and percentage text
-   - Show phase (hashing, embedding, encoding, etc.)
-
-2. **Templates** - Add progress bar markup to encode.html and decode.html
-
-### Files to Modify
-- `src/stegasoo/dct_steganography.py`
-- `frontends/web/app.py`
-- `frontends/web/static/js/stegasoo.js`
-- `frontends/web/templates/encode.html`
-- `frontends/web/templates/decode.html`
-
----
-
-## 2. Granular Decode Error Messages
-
-**Status:** Done
-
-**Problem:** Decode failures show generic "Decryption failed" - users don't know if it's wrong photo, wrong passphrase, wrong PIN, corrupted image, or format mismatch.
-
-**Solution:** Bubble up specific error types from library to UI
-
-### Implementation
-- Added new exceptions: InvalidMagicBytesError, ReedSolomonError, NoDataFoundError, ModeMismatchError
-- DCT decode now raises InvalidMagicBytesError for wrong magic bytes
-- DCT decode now raises ReedSolomonError (renamed from reedsolo's) for corruption
-- app.py catches specific exceptions with user-friendly messages:
-  - Invalid magic → "Try a different mode (LSB/DCT)"
-  - RS error → "Image too corrupted, may have been re-saved"
-  - Invalid header → "Image may have been modified"
-  - Decryption error → "Wrong credentials"
-
-### Files Modified
-- `src/stegasoo/exceptions.py` (new exceptions)
-- `src/stegasoo/__init__.py` (exports)
-- `src/stegasoo/dct_steganography.py` (raise specific exceptions)
-- `frontends/web/app.py` (catch and display)
-
----
-
-## 3. Mobile-Responsive Polish
-
-**Status:** Done
-
-**Problem:** UI works on mobile but has rough edges - cramped buttons, hard-to-tap targets, awkward layouts on small screens.
-
-**Solution:** Targeted CSS/layout fixes for mobile breakpoints
-
-### Areas to Improve
-
-1. **Encode/Decode Forms:**
-   - Stack image drop zones vertically on mobile (currently side-by-side)
-   - Larger touch targets for file inputs
-   - Full-width buttons on small screens
-   - Passphrase input readable at smaller sizes
-
-2. **Navigation:**
-   - Hamburger menu for mobile navbar (if not already)
-   - Sticky header doesn't eat too much screen
-   - Easy thumb reach for main actions
-
-3. **Results/Output:**
-   - Download buttons full-width on mobile
-   - QR codes sized appropriately
-   - Click-to-copy message box works well with touch
-
-4. **Drop Zones:**
-   - Larger tap targets
-   - Visual feedback for touch (not just hover)
-   - Camera integration hint on mobile ("Tap to take photo or choose file")
-
-### Testing Targets
-- iPhone SE (small)
-- iPhone 14 (medium)
-- iPad (tablet)
-- Android Chrome
-
-### Files to Modify
-- `frontends/web/static/css/style.css` (or new mobile.css)
-- `frontends/web/templates/encode.html`
-- `frontends/web/templates/decode.html`
-- `frontends/web/templates/base.html` (navbar)
-
----
-
-## Testing Checklist
-
-- [ ] Progress bar works on localhost
-- [ ] Progress bar works on Pi (slower, more visible)
-- [ ] Cancellation handling (what if user navigates away?)
-- [ ] Error states display correctly
-- [ ] Smoke test passes
-
----
-
-## 4. Forced First-Login Setup
-
-**Status:** Done
-
-**Problem:** Users can navigate the app without creating an admin account first. Should force password setup before anything else.
-
-**Solution:** Middleware/decorator that redirects to setup page if no users exist.
-
-### Implementation
-- Added `@app.before_request` hook that redirects to /setup if no users exist
-- Skips redirect for static files and setup-related routes
-
-### Files Modified
-- `frontends/web/app.py` (added require_setup before_request hook)
-
----
-
-## 5. Dropzone UX Fixes
-
-**Status:** Done
-
-**Problem:** Dropzone has some interaction bugs:
-- Dropzone doesn't clear properly if first QR image fails
-- Can't click on image preview to replace file (have to click surrounding border)
-
-**Solution:** Fix JS event handling and state management
-
-### Implementation
-- Added click handler on preview images to trigger file input
-- Made entire drop zone clickable (not just label)
-- QR zone now resets after 2 seconds on error, allowing retry
-- Clear file input on QR error so same file can be re-selected
-
-### Files Modified
-- `frontends/web/static/js/stegasoo.js`
-
----
-
-## 6. Smoke Test Benchmarking
-
-**Status:** Done
-
-**Problem:** No way to measure encode/decode performance or track regressions.
-
-**Solution:** Add timing to smoke tests using `hyperfine` or `time`.
-
-### Implementation
-- Added `--benchmark` flag to run encode/decode benchmarks after tests
-- Added `--runs=N` flag to customize number of benchmark runs (default: 5)
-- Uses hyperfine if available for precise timing with warmup
-- Falls back to manual timing with bc if hyperfine not installed
-- Outputs min/max/avg stats for both encode and decode operations
-
-### Files Modified
-- `tests/smoke-test.sh`
-
----
-
-## 7. Docker Cleanup
-
-**Status:** Done (4.1.1)
-
-**Problem:** Docker build context is larger than needed (includes test images, rpi scripts, etc.)
-
-**Solution:** Added `.dockerignore` and fixed volume permissions in Dockerfile
-
-### Files Modified
-- `.dockerignore` (created)
-- `Dockerfile` (instance dir permissions)
-
----
-
-## 8. Release Validation Script
-
-**Status:** Done
-
-**Problem:** Manual release checklist is error-prone. Need automated validation.
-
-**Solution:** Script that runs through testable checklist items
-
-### Features
-- Run pytest
-- Build and test Docker image
-- SSH to Pi and run smoke test (optional, if PI_IP provided)
-- Report pass/fail summary
-
-### Files to Create
-- `scripts/validate-release.sh`
-
----
-
-## 9. Smoke Test Docker Support
-
-**Status:** Done
-
-**Problem:** Smoke test expects systemd service, doesn't auto-create admin for Docker.
-
-**Solution:** Make smoke test Docker-aware
-
-### Features
-- Skip systemd checks if not on Pi/Linux with systemd
-- Auto-detect fresh Docker (no users) and create admin via /setup
-- Add `--docker` flag to skip Pi-specific checks
-
-### Implementation
-- Added `--docker` flag that sets localhost and skips SSH/systemd checks
-- Docker health check verifies container responds with HTTP 200/302
-- Header shows "Docker Smoke Test" in Docker mode
-
-### Files Modified
-- `rpi/smoke-test.sh`
-
----
-
-## Notes
-
-- Keep 4.1.2 focused - 9 features (9 done)
-- Don't break DCT compatibility (4.1.1 RS format is stable)
-- Test on Pi before release

PLAN-4.1.3.md

@@ -1,42 +0,0 @@
-# Stegasoo 4.1.3 Plan
-
-## Release Theme
-Performance and admin features.
-
----
-
-## 1. DCT Performance Optimizations
-
-**Status:** Planned
-
-**Problem:** DCT encode/decode can be slow on Pi, especially for large images.
-
-**Ideas:**
-- Vectorize block processing with NumPy
-- Reduce Python loop overhead
-- Parallel block processing (multiprocessing?)
-- Profile and identify bottlenecks
-- Consider Cython for hot paths
-
----
-
-## 2. User Management UI
-
-**Status:** Planned
-
-**Problem:** No way for admin to manage users via UI. Currently need direct DB access.
-
-**Features:**
-- List all users
-- Create new user (admin only)
-- Delete user (admin only)
-- Reset user password
-- User activity/last login
-
----
-
-## Notes
-
-- These are heavier lifts than 4.1.2
-- Profile before optimizing
-- Consider security implications of user management

PLAN-4.1.4.md

@@ -1,165 +0,0 @@
-# Stegasoo 4.1.4 Plan
-
-## Build / Deploy
-- [x] Pre-built Python 3.12 venv tarball for Pi (skip 20+ min compile) - see details below
-- [x] Fixed partition sizing in flash script (16GB rootfs for faster imaging)
-- [x] Rename `flash-pi.sh` → `flash-stock-img.sh` for clarity
-- [x] pip-audit integration in release validation
-
-### Pi venv Tarball Approach
-1. Flash fresh Pi image, let it fully build (20+ min compile)
-2. Once running and working, SSH in and create optimized tarball:
-   ```bash
-   cd /opt/stegasoo
-   # Strip caches and tests (295MB → 208MB)
-   find venv/ -type d -name '__pycache__' -exec rm -rf {} + 2>/dev/null
-   find venv/ -type d -name 'tests' -exec rm -rf {} + 2>/dev/null
-   find venv/ -type d -name 'test' -exec rm -rf {} + 2>/dev/null
-   # Compress with zstd (208MB → 39MB)
-   tar -cf - venv/ | zstd -19 -T0 > /tmp/stegasoo-venv-pi-arm64.tar.zst
-   ```
-3. Pull tarball to host: `scp admin@pi:/tmp/stegasoo-venv-pi-arm64.tar.zst rpi/`
-4. setup.sh auto-detects and extracts tarball if present in rpi/
-5. Re-flash and test fresh build with pre-built venv (should be <2 min vs 20+)
-
-## Features
-- [x] QR channel key sharing (see detailed plan below)
-- [ ] Role-based permissions: admin / mod / user
-- [x] `stegasoo info` fastfetch-style command (version, service status, channel, CPU, temp, etc.)
-- [ ] Better capacity estimates / pre-flight check before encode fails
-
----
-
-## QR Channel Key Sharing - Implementation Plan
-
-### Current State
-- ✅ **CLI**: `stegasoo channel qr` generates ASCII/PNG QR for server channel key
-- ✅ **Web UI (about.html)**: Client-side QR generator exists - input key, generate/show QR, download PNG
-- ✅ **Account page**: Shows saved channel keys with fingerprint, rename, delete
-- ❌ No role restrictions on QR sharing
-- ❌ No QR button for saved keys on account page
-- ❌ No QR scanning to import keys
-
-### Design Decisions
-
-**UI Placement** (avoiding encode/decode page crowding):
-- Keep QR generator in **about.html** (already exists, logical place for tools)
-- Add QR button to **account.html** saved keys (small icon, doesn't crowd)
-- Both should be admin-only
-
-**Role Restriction** (per user request):
-- QR sharing = admin only (hide generator + saved key QR buttons from non-admins)
-- Prerequisite: Need role-based permissions feature first
-- Interim option: Just hide from non-admin users using existing `is_admin` flag
-
-### Implementation Steps
-
-#### Phase 1: Admin-only restriction (quick win)
-1. **about.html**: Wrap QR generator section in `{% if is_admin %}` block
-2. **Account route**: Pass `is_admin` to template (if not already)
-3. **account.html**: Add small QR icon button to saved keys row (admin only)
-   - Opens modal with QR canvas (reuse qrcode.js pattern from about.html)
-   - Download PNG button in modal
-
-#### Phase 2: QR Import (optional enhancement)
-1. Add "Import via QR" button to account.html key-add section
-2. Use device camera or file upload to scan QR
-3. Decode and populate channel_key input field
-4. Requires `pyzbar` on server OR client-side JS library like `jsQR`
-
-### Files to Modify
-
-```
-frontends/web/app.py
-  - about() route: Add missing vars: is_admin, channel_configured,
-    channel_fingerprint, channel_source (BUG: currently not passed!)
-  - account() route: ✅ Already passes is_admin
-
-frontends/web/templates/about.html
-  - Wrap channel key QR section in {% if is_admin %}
-
-frontends/web/templates/account.html
-  - Add QR button to saved keys (admin only)
-  - Add QR modal (copy pattern from about.html)
-  - Include qrcode.min.js CDN script
-```
-
-### Bug Found During Research
-The about.html template uses `channel_configured`, `channel_fingerprint`,
-`channel_source` but the route doesn't pass them - always shows "public mode".
-Fix this while implementing QR admin restriction.
-
-### Exact Code Changes
-
-**app.py - Fix about() route (around line 1564):**
-```python
-@app.route("/about")
-def about():
-    from stegasoo.channel import get_channel_status
-    channel_status = get_channel_status()
-
-    # Check if user is admin (for QR sharing)
-    current_user = get_current_user()
-    is_admin = current_user.is_admin if current_user else False
-
-    return render_template(
-        "about.html",
-        has_argon2=has_argon2(),
-        has_qrcode_read=HAS_QRCODE_READ,
-        # Channel info (bugfix)
-        channel_configured=channel_status["configured"],
-        channel_fingerprint=channel_status.get("fingerprint"),
-        channel_source=channel_status.get("source"),
-        # Admin check for QR sharing
-        is_admin=is_admin,
-    )
-```
-
-### Template Changes Preview
-
-**account.html - Add to saved key row:**
-```html
-{% if is_admin %}
-<button type="button" class="btn btn-outline-info btn-sm"
-        onclick="showKeyQr('{{ key.channel_key }}')" title="Show QR">
-    <i class="bi bi-qr-code"></i>
-</button>
-{% endif %}
-```
-
-**about.html - Wrap existing section:**
-```html
-{% if is_admin %}
-<!-- Channel Key QR Generator -->
-<div class="card bg-dark border-secondary">
-    ...existing QR generator...
-</div>
-{% endif %}
-```
-
-### Testing Checklist (Phase 1 Implemented)
-- [ ] Non-admin users cannot see QR generator in about.html
-- [ ] Non-admin users cannot see QR buttons on account page
-- [ ] Admin users can generate QR for any saved key
-- [ ] QR downloads work correctly
-- [ ] QR scans correctly with phone camera
-
-### Implementation Status
-**Phase 1: COMPLETE** - Admin-only QR sharing implemented:
-- `app.py`: Fixed about() route to pass channel status + is_admin
-- `about.html`: QR generator wrapped in `{% if is_admin %}` with Admin badge
-- `account.html`: QR button added to saved keys (admin only), modal + JS for generation/download
-
----
-
-## Security
-- [ ] Optional encryption for temp file storage (paranoid mode, config toggle)
-
-## Docs
-- [x] Update UNDER_THE_HOOD.md (v4.1 changes, channel keys)
-- [ ] General docs refresh
-
-## Ideas (maybe later)
-- [ ] Stego detection tool
-- [ ] Browser extension
-- [ ] Pi snapshot/backup feature

PLAN-4.1.5.md

@@ -1,106 +0,0 @@
-# Stegasoo 4.1.5 Plan
-
-## Decode Progress Bar (Real Progress)
-
-Mirror the encode async pattern for decode operations.
-
-### Backend Changes
-
-**1. Add async mode to `/decode` route (`app.py`)**
-- Check for `async=true` form param
-- Generate job_id, store job, submit to executor
-- Return `{"job_id": ..., "status": "pending"}` immediately
-
-**2. Add decode status/progress endpoints (`app.py`)**
-```python
-@app.route("/decode/status/<job_id>")
-def decode_status(job_id):
-    # Return {"status": "pending|running|complete|error", "result": {...}}
-
-@app.route("/decode/progress/<job_id>")
-def decode_progress(job_id):
-    # Read from /tmp/stegasoo_progress_{job_id}.json
-    # Return {"percent": 0-100, "phase": "..."}
-```
-
-**3. Add `_run_decode_job()` background worker (`app.py`)**
-- Similar to `_run_encode_job()`
-- Pass `progress_file` param to decode function
-- Store result/error in job dict
-
-**4. Update decode functions to write progress (`lsb_steganography.py`, `dct_steganography.py`)**
-
-Phases for decode:
-- `"starting"` (0%)
-- `"reading"` (10%) - reading stego image
-- `"extracting"` (30%) - extracting hidden data
-- `"decrypting"` (60%) - Argon2 + AES decryption
-- `"verifying"` (80%) - HMAC verification
-- `"finalizing"` (95%) - preparing output
-- `"complete"` (100%)
-
-### Frontend Changes
-
-**5. Update decode form submission (`decode.html`)**
-- Add async form handler like encode
-- Call `Stegasoo.submitDecodeAsync(form, btn)`
-
-**6. Add decode async methods (`stegasoo.js`)**
-```javascript
-submitDecodeAsync(form, btn)     // POST with async=true, show modal
-pollDecodeProgress(jobId)        // Poll /decode/status, /decode/progress
-```
-
-Reuse existing:
-- `showProgressModal('Decoding')`
-- `updateProgress(percent, phase)`
-
-**7. Handle decode result redirect**
-- On complete: redirect to `/decode/result/{file_id}` or display inline
-
-### Files to Modify
-
-```
-frontends/web/app.py
-  - Add async handling to /decode route (~line 1300+)
-  - Add /decode/status/<job_id> endpoint
-  - Add /decode/progress/<job_id> endpoint
-  - Add _run_decode_job() function
-
-frontends/web/static/js/stegasoo.js
-  - Add submitDecodeAsync()
-  - Add pollDecodeProgress()
-
-frontends/web/templates/decode.html
-  - Update form submit to use async mode
-
-src/stegasoo/lsb_steganography.py
-  - Add progress_file param to decode()
-  - Write progress at each phase
-
-src/stegasoo/dct_steganography.py
-  - Add progress_file param to decode()
-  - Write progress at each phase
-```
-
-### Testing Checklist
-
-- [ ] Decode shows progress modal on submit
-- [ ] Progress bar animates through phases
-- [ ] Successful decode redirects to result
-- [ ] Failed decode shows error in modal
-- [ ] Works for both LSB and DCT modes
-- [ ] Works for message and file payloads
-- [ ] Progress file cleaned up after completion
-
----
-
-## Other 4.1.5 Ideas (if time)
-
-- [ ] Role-based permissions: admin / mod / user
-- [ ] Better capacity estimates / pre-flight check
-- [ ] Stego detection tool
-
-## Bugs / Nice to Have
-
-- [ ] **flash-stock-img.sh 16GB resize not working** - partition still full SD size after flash, makes dd pull slow. Investigate resize2fs/parted logic and test fix.

PLAN-4.1.6.md

@@ -0,0 +1,97 @@
+# Stegasoo v4.1.6 Planning
+
+## UI Tweaks
+
+### 1. Revamp Tron Lines Animation (Carrier/Stego Image)
+**Current state:**
+- 6-8 snake paths, each with 3-5 segments (~24-40 total lines)
+- 2px thick lines
+- 30-60px length per segment
+- Starting points spread across 80% of image area
+- Colors: yellow, cyan, purple, blue with glow
+
+**Target improvements:**
+- [x] Thinner lines (1px instead of 2px)
+- [x] More numerous (20-40 paths via 5x4 grid, ~60-200 segments total)
+- [x] Better distribution across entire image (grid-based seeding)
+- [x] Shorter segments (12-30px) for denser "circuit board" look
+
+**Files:**
+- `frontends/web/static/style.css` (~881-979) - `.embed-trace` styling
+- `frontends/web/static/js/stegasoo.js` (~333-390) - `generateEmbedTraces()`
+
+---
+
+## Tools Page Expansion
+
+### Analysis Tools
+- [x] **JPEG Compression Tester** - Preview image at different quality levels (10-100%), show file size delta. Useful for understanding stego survivability.
+- [ ] **LSB Plane Viewer** - Visualize least significant bit plane(s) of RGB channels. Classic stego analysis tool.
+- [ ] **Histogram Viewer** - Color distribution graph per channel. Anomalies can indicate hidden data.
+- [ ] **Image Diff** - Compare two images side-by-side with pixel difference highlighting. Great for original vs stego comparison.
+- [ ] **Noise Analysis** - Chi-square or similar statistical analysis for detecting LSB embedding.
+
+### Transform Tools
+- [x] **Rotate/Flip** - 90°/180°/270° rotation, horizontal/vertical flip
+- [ ] **Resize** - Scale with aspect ratio lock, common presets (50%, 25%, etc.)
+- [ ] **Crop** - Basic rectangular crop with preview
+- [x] **Format Convert** - PNG ↔ JPEG ↔ WebP with quality slider
+
+### Existing Tools (already done)
+- [x] Capacity Calculator
+- [x] EXIF Viewer
+- [x] EXIF Strip
+- [x] Image Peek (header analysis)
+
+### Tools UI/UX Overhaul
+
+**Final Layout: Office-style Ribbon + Two-Panel**
+```
+┌─────────────────────────────────────────────────────────────┐
+│  📏  📋  👁️  📊  ┃  ✂️  🔄  📐  🔀      Image Tools         │ ← Icon toolbar
+├────────────────────────────────────────┬────────────────────┤
+│  [Format: PNG ▼] [Quality: 85]         │                    │
+├────────────────────────────────────────┤  Capacity          │
+│                                        │  Calculator        │
+│    ┌────────────────────────────┐     │  ──────────────    │
+│    │                            │     │                    │
+│    │      Drop image here       │     │  Dimensions:       │
+│    │         or click           │     │  1920 × 1080       │
+│    │                            │     │                    │
+│    └────────────────────────────┘     │  LSB Capacity:     │
+│                                        │  245 KB            │
+│           [image.jpg]                  │                    │
+│                                        │  ──────────────    │
+│                                        │  [Clear] [Export]  │
+└────────────────────────────────────────┴────────────────────┘
+      Options + dropzone/preview             Results sidebar
+```
+
+- Top ribbon: Icon buttons grouped by category (Analyze | Transform)
+- Left panel: Tool options + dropzone/preview (INPUT)
+- Right panel: Tool name + results/metadata + actions (OUTPUT)
+- Flow: Left → Right (input → output)
+
+**Implementation Tasks:**
+- [x] Move inline CSS to style.css
+- [x] Build icon toolbar ribbon
+- [x] Build two-panel layout structure
+- [x] Migrate existing tools (Capacity, EXIF, Strip)
+- [x] Add new tools (Rotate, Compress, Convert)
+- [ ] Loading spinner on all async operations
+- [ ] Toast notifications instead of alerts
+- [ ] Consistent color coding (green=analysis, amber=transform)
+- [ ] Mobile: stack panels vertically
+
+---
+
+## CLI Improvements
+
+### (Add items here)
+
+---
+
+## Other UI Tweaks
+
+### (Add items here)
+

README.md

@@ -105,15 +105,18 @@ ruff check src/ tests/ frontends/
 ## Docker
 
 ```bash
-# Quick start
-docker-compose up -d
+# Quick start (HTTPS enabled by default)
+docker-compose -f docker/docker-compose.yml up -d
 
 # Access
-# Web UI:   http://localhost:5000
+# Web UI:   https://localhost:5000  (self-signed cert)
 # REST API: http://localhost:8000
+
+# Disable HTTPS if needed:
+STEGASOO_HTTPS_ENABLED=false docker-compose -f docker/docker-compose.yml up -d
 ```
 
-See [DOCKER.md](DOCKER.md) for full documentation.
+See [DOCKER.md](DOCKER.md) and [docs/DOCKER_QUICKSTART.md](docs/DOCKER_QUICKSTART.md) for full documentation.
 
 ## Raspberry Pi
 
@@ -143,6 +146,7 @@ See [rpi/README.md](rpi/README.md) for manual installation.
 - [UNDER_THE_HOOD.md](UNDER_THE_HOOD.md) - Technical deep-dive
 - [CHANGELOG.md](CHANGELOG.md) - Version history
 - [CONTRIBUTING.md](CONTRIBUTING.md) - Contributor guide
+- `man stegasoo` - Man page (install: `sudo cp docs/stegasoo.1 /usr/local/share/man/man1/ && sudo mandb`)
 
 ## License
 

RELEASE-4.1.1.md

@@ -1,93 +0,0 @@
-# Stegasoo 4.1.1 Release Notes
-
-**Release Date:** January 5, 2026
-
-## Highlights
-
-- **Reed-Solomon Error Correction** - DCT steganography now includes RS error correction, making encoded images more resilient to minor corruption and compression artifacts
-- **Completely Rewritten Pi Setup** - Fresh install tested and validated, works reliably from scratch
-- **SSH Login Banner** - See your Stegasoo URL immediately on SSH login
-
-## New Features
-
-### Reed-Solomon Error Correction
-DCT-encoded images now include Reed-Solomon error correction codes, allowing recovery from minor image corruption. This significantly improves reliability when images are shared through platforms that may slightly modify them.
-
-### SSH Login Banner (MOTD)
-When you SSH into your Stegasoo Pi, you'll now see:
-```
-  ___  _____  ___    ___    _    ___    ___    ___
- / __||_   _|| __|  / __|  /_\  / __|  / _ \  / _ \
- \__ \  | |  | _|  | (_ | / _ \ \__ \ | (_) || (_) |
- |___/  |_|  |___|  \___//_/ \_\|___/  \___/  \___/
-
- ● Stegasoo is running
-   https://192.168.0.4
-```
-
-### Elapsed Time Counter
-Encode/decode buttons now show elapsed time during operations.
-
-### Click-to-Copy Decoded Message
-Click the decoded message box to copy to clipboard (no button needed).
-
-### Overclock Wizard Option
-First-boot wizard now offers optional CPU overclocking for Pi 4/5 with active cooling.
-
-## Improvements
-
-### Setup Script (setup.sh)
-- Fixed pyenv Python path resolution (handles 3.12 → 3.12.12 mapping)
-- Changed default install location to `/opt/stegasoo`
-- Fixed jpegio build order (clone stegasoo first, then build jpegio into venv)
-- Added python3-dev to dependencies
-- Added btop for system monitoring
-- Shows `/setup` URL at completion for admin account creation
-
-### Sanitize Script
-- Now clears port 443 iptables redirect (clean slate for wizard)
-- Removes overclock settings before imaging
-
-### Documentation
-- Updated all docs to reference `/opt/stegasoo` path
-- Added pre-setup steps (chown /opt, install git)
-- Added Pi 4 performance baseline (~60s for 10MB JPEG)
-
-### About Page
-- Redesigned "Limits & Specs" section with key stats cards and accordion
-
-## Bug Fixes
-
-- Fixed DCT steganography for non-8-aligned images
-- Fixed MOTD port detection (was using iptables which requires root)
-- Fixed smoke test `--443` flag parsing
-
-## Performance
-
-On a Raspberry Pi 4 at 2GHz with USB 3.0 NVMe:
-- ~50 seconds to encode a 10MB JPEG
-- ~60 seconds to decode a 10MB JPEG
-- Full encryption: passphrase + PIN + reference photo
-
-## Upgrade Notes
-
-If upgrading from 4.1.0:
-```bash
-cd /opt/stegasoo  # or ~/stegasoo
-git pull origin 4.1
-```
-
-For fresh installs, see the [Pi README](rpi/README.md).
-
-## Pre-built Images
-
-- `stegasoo-rpi-4.1.1_20260105-2.img.zst` - Raspberry Pi 4/5 image
-
-Flash with:
-```bash
-zstdcat stegasoo-rpi-4.1.1_20260105-2.img.zst | sudo dd of=/dev/sdX bs=4M status=progress
-```
-
----
-
-Full changelog: [v4.1.0...v4.1.1](https://github.com/adlee-was-taken/stegasoo/compare/v4.1.0...v4.1.1)

RELEASE_CHECKLIST.md

@@ -21,12 +21,12 @@ Pre-release validation checklist. Complete all items before tagging a release.
 
 ## Docker Validation
 
-- [ ] Base image builds: `docker build -f Dockerfile.base -t stegasoo-base:latest .`
-- [ ] Web image builds: `docker-compose build web`
-- [ ] Container starts: `docker-compose up -d web`
+- [ ] Base image builds: `docker build -f docker/Dockerfile.base -t stegasoo-base:latest .`
+- [ ] Web image builds: `docker-compose -f docker/docker-compose.yml build web`
+- [ ] Container starts: `docker-compose -f docker/docker-compose.yml up -d web`
 - [ ] Web UI accessible at http://localhost:5000
 - [ ] Encode/decode works in container
-- [ ] Container stops cleanly: `docker-compose down`
+- [ ] Container stops cleanly: `docker-compose -f docker/docker-compose.yml down`
 
 ## Release Process
 

RELEASE_NOTES.md

@@ -1,34 +1,86 @@
-## Stegasoo v4.1.3
+## Stegasoo v4.2.0
 
-### Fixes
-- **SSL Certificate Generation**: First-boot wizard now properly generates self-signed certs when HTTPS is enabled
-- **Download Bug Fixed**: No more "File expired or not found" errors - fixed multi-worker temp file sharing
-- **Docker Build**: Reduced build context from 2.3GB to ~900KB
+### Performance Optimizations
 
-### Improvements
-- Docker memory limits increased to 2GB (prevents OOM on large DCT operations)
-- Decode button now shows loading spinner during processing
-- Headless Pi flash script with Trixie/NetworkManager support
+Major performance improvements for Raspberry Pi and resource-constrained deployments.
+
+#### DCT Vectorization (~14x faster)
+- Batch DCT processing using `scipy.fft.dctn` with `axes=(1,2)`
+- Processes 500 blocks at once instead of one-by-one
+- Decode time reduced from ~2.6s to ~0.8s on 1MB images
+
+#### Memory Optimization (50% reduction)
+- Switched from `float64` to `float32` for all DCT operations
+- Peak RAM: 211 MB → 107 MB for encode, 104 MB → 52 MB for decode
+- Critical for Pi 3/4 avoiding swap thrashing
+
+#### Progress Callbacks for Decode
+- `progress_file` parameter added to `decode()` and extraction functions
+- UI can now show decode progress (phases: loading, extracting, decoding, complete)
+- JSON format: `{"current": 80, "total": 100, "percent": 80.0, "phase": "decoding"}`
+
+#### Async API Endpoints
+- Encode/decode operations now run in thread pool via `asyncio.to_thread()`
+- API server can handle concurrent requests without blocking
+- Essential for multi-user Pi deployments
+
+### Compression
+
+#### Zstd Default Compression
+- `zstandard` is now a core dependency (always installed)
+- Better compression ratio than zlib for QR code RSA keys
+- New `STEGASOO-ZS:` prefix for zstd, backward compatible with `STEGASOO-Z:` (zlib)
+
+### QR Code Generation
+
+#### CLI Support
+- `stegasoo generate --rsa --qr key.png` - save RSA key as QR image (PNG/JPG)
+- `stegasoo generate --rsa --qr-ascii` - print ASCII QR to terminal
+
+#### API Support
+- `POST /generate-key-qr` - generate QR from RSA key
+- Supports `png`, `jpg`, and `ascii` output formats
+- Uses zstd compression by default
+
+### Other Changes
+
+- RSA key size capped at 3072 bits (4096 too large for QR codes)
+- File auto-expire increased to 10 minutes
+- Progress bar "candy cane" animation during Argon2 key derivation
+- Optional API service in Pi setup (with security warning)
+
+### Summary
+
+| Metric | v4.1.7 | v4.2.0 | Improvement |
+|--------|--------|--------|-------------|
+| Decode (1MB) | ~2.6s | ~0.8s | **70% faster** |
+| Peak RAM | 211 MB | 107 MB | **50% less** |
+| Concurrent API | No | Yes | ✓ |
+| QR Compression | zlib | zstd | **~15% smaller** |
+
+### Raspberry Pi Image
+Download `stegasoo-rpi-4.2.0_final.img.zst` from Releases.
+
+```bash
+# Flash (auto-detects SD card)
+sudo ./rpi/flash-image.sh stegasoo-rpi-4.2.0_final.img.zst
+
+# Or manual
+zstdcat stegasoo-rpi-4.2.0_final.img.zst | sudo dd of=/dev/sdX bs=4M status=progress
+```
+
+Default login: `admin` / `stegasoo`
 
 ### Docker
 ```bash
-docker-compose up -d web  # Web UI on :5000
-docker-compose up -d api  # REST API on :8000
-```
+# Build and run
+docker build -f docker/Dockerfile.base -t stegasoo-base:latest .
+docker-compose -f docker/docker-compose.yml up -d
 
-### Raspberry Pi Image
-Download `stegasoo-rpi-4.1.3.img.zst`, flash to SD card, and boot. The first-boot wizard will guide you through WiFi, HTTPS, and channel key setup.
-
-```bash
-# Flash with included script
-./rpi/flash-image.sh stegasoo-rpi-4.1.3.img.zst /dev/sdX
-
-# First time: save your WiFi credentials
-./rpi/inject-wifi.sh --setup
-
-# Then inject WiFi after flashing
-sudo ./rpi/inject-wifi.sh /dev/sdX
+# Or individual services
+docker-compose -f docker/docker-compose.yml up -d web  # Web UI on :5000
+docker-compose -f docker/docker-compose.yml up -d api  # REST API on :8000
 ```
 
 ### Full Changelog
-See [CHANGELOG.md](CHANGELOG.md) for complete details.
+See [CHANGELOG.md](CHANGELOG.md) for complete version history.

SECURITY_AUDIT_PLAN.md

@@ -0,0 +1,284 @@
+# Stegasoo Security Audit Plan
+
+> **Target Audience**: Developers, security reviewers, and deployment administrators
+> **Scope**: Web UI, REST API, CLI, and cryptographic core
+> **Deployment Model**: Air-gapped / private LAN (primary), Internet-facing (secondary)
+
+---
+
+## Overview
+
+Stegasoo is a steganography tool designed for **air-gapped deployments** on private networks. While the primary threat model assumes a trusted local network, this audit plan covers security best practices for both isolated and potentially exposed deployments.
+
+### Known Limitations (By Design)
+
+- **Self-signed certificates**: HTTPS uses self-signed certs; users must add exceptions or deploy their own CA
+- **No rate limiting**: Assumes trusted users on private network
+- **Single-node**: No distributed session store; sessions are per-instance
+- **Air-gap focus**: External security (firewalls, network isolation) is user's responsibility
+
+---
+
+## 1. Authentication & Authorization
+
+### 1.1 Password Security
+- [ ] Passwords hashed with Argon2id (preferred) or PBKDF2 fallback
+- [ ] Minimum password length enforced (8+ characters)
+- [ ] Password not logged or exposed in error messages
+- [ ] Password change requires current password verification
+- [ ] Admin re-authentication required for sensitive operations (channel key export)
+
+### 1.2 Session Management
+- [ ] Session tokens are cryptographically random
+- [ ] Session cookies have `HttpOnly` flag
+- [ ] Session cookies have `Secure` flag (when HTTPS enabled)
+- [ ] Session cookies have `SameSite` attribute
+- [ ] Sessions invalidated on logout
+- [ ] Sessions invalidated on password change
+- [ ] Session timeout configured appropriately
+
+### 1.3 Authorization
+- [ ] Admin-only routes protected by `@admin_required` decorator
+- [ ] User-only routes protected by `@login_required` decorator
+- [ ] Users cannot access other users' saved channel keys
+- [ ] Users cannot modify other users' accounts
+- [ ] Role escalation not possible through API manipulation
+
+---
+
+## 2. Cryptographic Implementation
+
+### 2.1 Key Derivation
+- [ ] KDF uses Argon2id with appropriate parameters (memory, iterations, parallelism)
+- [ ] PBKDF2 fallback uses sufficient iterations (600,000+)
+- [ ] Salt is cryptographically random and unique per operation
+- [ ] PIN/passphrase combined securely before KDF
+
+### 2.2 Encryption
+- [ ] AES-256-GCM used for payload encryption
+- [ ] Nonce/IV is unique per encryption operation
+- [ ] Authentication tag verified before decryption
+- [ ] No padding oracle vulnerabilities
+
+### 2.3 Channel Keys
+- [ ] Channel keys are 128-bit (32 hex chars)
+- [ ] Channel key derivation uses HKDF or similar
+- [ ] Channel isolation prevents cross-channel decryption
+- [ ] Fingerprint reveals no information about full key
+
+### 2.4 Random Number Generation
+- [ ] All random values use `secrets` module or OS CSPRNG
+- [ ] No use of `random` module for security-sensitive operations
+
+---
+
+## 3. Input Validation & Injection Prevention
+
+### 3.1 Web UI
+- [ ] All user input sanitized before rendering (XSS prevention)
+- [ ] Jinja2 auto-escaping enabled
+- [ ] No `| safe` filter on user-controlled content
+- [ ] Content-Security-Policy header configured
+- [ ] X-Content-Type-Options: nosniff
+
+### 3.2 File Uploads
+- [ ] File size limits enforced server-side
+- [ ] File type validation (magic bytes, not just extension)
+- [ ] Uploaded files not executed
+- [ ] Filenames sanitized (path traversal prevention)
+- [ ] Temporary files cleaned up after processing
+
+### 3.3 API Inputs
+- [ ] JSON schema validation on API endpoints
+- [ ] Integer overflow checks on size parameters
+- [ ] No SQL injection (parameterized queries only)
+- [ ] No command injection (no shell=True with user input)
+
+---
+
+## 4. Steganography-Specific Security
+
+### 4.1 Carrier Image Handling
+- [ ] Malformed images don't crash the server (PIL/jpegio hardening)
+- [ ] DCT mode subprocess isolation for crash protection
+- [ ] Memory limits on image processing
+- [ ] No arbitrary code execution from image metadata
+
+### 4.2 Payload Security
+- [ ] Payload size limits enforced
+- [ ] Encrypted payload indistinguishable from random noise
+- [ ] No metadata leakage in output images
+- [ ] Reference photo required (prevents dictionary attacks)
+
+### 4.3 Capacity Reporting
+- [ ] Capacity calculation doesn't leak information about encoding method
+- [ ] Failed decodes don't reveal why (wrong key vs no data vs corrupted)
+
+---
+
+## 5. Network & Transport Security
+
+### 5.1 HTTPS Configuration
+- [ ] TLS 1.2+ only (no SSLv3, TLS 1.0/1.1)
+- [ ] Strong cipher suites configured
+- [ ] Certificate generation uses 2048+ bit RSA or P-256 EC
+- [ ] Private key file permissions restricted (600)
+
+### 5.2 Headers
+- [ ] X-Frame-Options: DENY (clickjacking prevention)
+- [ ] X-Content-Type-Options: nosniff
+- [ ] Referrer-Policy: same-origin
+- [ ] Permissions-Policy configured
+
+### 5.3 CORS (if applicable)
+- [ ] CORS not enabled (or restricted to specific origins)
+- [ ] Credentials not allowed cross-origin
+
+---
+
+## 6. Error Handling & Logging
+
+### 6.1 Error Messages
+- [ ] Stack traces not exposed to users in production
+- [ ] Error messages don't reveal sensitive paths or config
+- [ ] Failed login doesn't reveal if username exists
+
+### 6.2 Logging
+- [ ] Passwords never logged
+- [ ] Channel keys never logged
+- [ ] Passphrases never logged
+- [ ] Log files have appropriate permissions
+- [ ] Sensitive operations logged for audit trail (optional)
+
+---
+
+## 7. Dependency Security
+
+### 7.1 Python Dependencies
+- [ ] All dependencies pinned to specific versions
+- [ ] No known vulnerabilities in dependencies (run `pip-audit` or `safety`)
+- [ ] Dependencies from trusted sources only (PyPI)
+
+### 7.2 Frontend Dependencies
+- [ ] All JS/CSS served locally (air-gap ready)
+- [ ] No CDN dependencies
+- [ ] Bootstrap and libraries are official releases
+- [ ] Subresource integrity considered for any external loads
+
+---
+
+## 8. Deployment Security
+
+### 8.1 File Permissions
+- [ ] Database file not world-readable (600 or 640)
+- [ ] SSL certificates/keys not world-readable
+- [ ] Config files with secrets protected
+- [ ] Instance directory not in web root
+
+### 8.2 Docker Deployment
+- [ ] Container runs as non-root user
+- [ ] No unnecessary capabilities
+- [ ] Resource limits configured
+- [ ] Health checks don't expose sensitive info
+
+### 8.3 Raspberry Pi Deployment
+- [ ] Default passwords changed
+- [ ] SSH key-only authentication (recommended)
+- [ ] Unnecessary services disabled
+- [ ] Firewall configured (UFW/iptables)
+
+---
+
+## 9. Air-Gap Specific Considerations
+
+### 9.1 Network Isolation
+- [ ] Document expected network topology
+- [ ] No phone-home or telemetry
+- [ ] No external API calls
+- [ ] Works fully offline after deployment
+
+### 9.2 Key Distribution
+- [ ] QR code export for channel keys (offline transfer)
+- [ ] Print sheet for physical key backup
+- [ ] No cloud sync or external key servers
+
+### 9.3 Updates
+- [ ] Document offline update procedure
+- [ ] Signed releases (future consideration)
+- [ ] Checksum verification for downloads
+
+---
+
+## 10. Penetration Testing Checklist
+
+### 10.1 Authentication Attacks
+- [ ] Brute force login (note: no rate limiting by design)
+- [ ] Session fixation
+- [ ] Session hijacking
+- [ ] Password reset flow abuse
+
+### 10.2 Injection Attacks
+- [ ] SQL injection on all inputs
+- [ ] XSS (stored, reflected, DOM-based)
+- [ ] Command injection
+- [ ] Path traversal
+- [ ] SSTI (Server-Side Template Injection)
+
+### 10.3 Business Logic
+- [ ] Access control bypass
+- [ ] IDOR (Insecure Direct Object Reference)
+- [ ] Race conditions
+- [ ] Integer overflow in capacity calculations
+
+### 10.4 Cryptographic Attacks
+- [ ] Known-plaintext attacks on stego output
+- [ ] Timing attacks on password verification
+- [ ] Padding oracle attacks
+- [ ] Key reuse vulnerabilities
+
+---
+
+## Tools for Automated Testing
+
+```bash
+# Dependency vulnerability scan
+pip-audit
+safety check
+
+# Static analysis
+bandit -r stegasoo/ frontends/
+
+# Web security scan (if exposed)
+nikto -h https://localhost:5000
+OWASP ZAP (manual)
+
+# SSL/TLS configuration
+testssl.sh https://localhost:5000
+
+# Python code quality
+ruff check .
+mypy stegasoo/
+```
+
+---
+
+## Audit Schedule
+
+| Phase | Focus Area | Priority |
+|-------|-----------|----------|
+| Pre-release | Crypto implementation, auth flow | Critical |
+| Post-release | Dependency scan, static analysis | High |
+| Quarterly | Full penetration test | Medium |
+| Ongoing | CVE monitoring for dependencies | High |
+
+---
+
+## Notes
+
+- This plan assumes **trusted users on a private network** as the primary deployment model
+- Internet-facing deployments should add rate limiting, fail2ban, and reverse proxy hardening
+- For high-security deployments, consider external security audit by professionals
+
+---
+
+*Last updated: 2026-01-07*

WEB_UI.md

@@ -177,7 +177,7 @@ python app.py
 ### Docker Configuration
 
 ```yaml
-# docker-compose.yml
+# docker/docker-compose.yml
 services:
   web:
     environment:
@@ -360,7 +360,7 @@ gunicorn --bind 0.0.0.0:5000 --workers 2 --threads 4 --timeout 60 app:app
 
 **Docker:**
 ```bash
-docker-compose up web
+docker-compose -f docker/docker-compose.yml up web
 ```
 
 ### First-Time Setup
@@ -411,7 +411,7 @@ Create a new set of credentials for steganography operations.
 | Use PIN | on/off | on | Generate a numeric PIN |
 | PIN length | 6-9 | 6 | Digits in the PIN |
 | Use RSA Key | on/off | off | Generate an RSA key pair |
-| RSA key size | 2048/3072/4096 | 2048 | Key size in bits |
+| RSA key size | 2048/3072 | 2048 | Key size in bits |
 
 #### Entropy Calculator
 
@@ -1245,7 +1245,7 @@ volumes:
 ```bash
 pip install scipy
 # Or rebuild Docker image
-docker-compose build --no-cache
+docker-compose -f docker/docker-compose.yml build --no-cache
 ```
 
 ### Browser Compatibility

WISHLIST-4.2.md

@@ -0,0 +1,42 @@
+# Stegasoo v4.2 Wishlist
+
+Blue sky ideas for future development. No timeline - just capturing thoughts.
+
+---
+
+## Performance
+
+### GPU-Accelerated DCT Encoding/Decoding
+- **Idea**: Leverage GPU for JPEG DCT coefficient manipulation
+- **Potential Approaches**:
+  - OpenCL/CUDA for parallel DCT operations
+  - Raspberry Pi VideoCore IV/VI GPU compute
+  - WebGPU for browser-based acceleration
+- **Challenges**:
+  - jpegio library is CPU-bound (C extension)
+  - Would need custom DCT implementation
+  - Memory transfer overhead may negate gains for small images
+- **Research**:
+  - libjpeg-turbo uses SIMD but not GPU
+  - nvJPEG (NVIDIA) does GPU-accelerated JPEG
+  - Could potentially use GPU for the embedding math, not JPEG decode
+
+---
+
+## Features
+
+(Add ideas here)
+
+---
+
+## Infrastructure
+
+(Add ideas here)
+
+---
+
+## Notes
+
+- This is a living document - add ideas anytime
+- Not all ideas will be implemented
+- Feasibility research needed before committing to roadmap

aur/PKGBUILD

@@ -0,0 +1,116 @@
+# Maintainer: Aaron D. Lee <your-email@example.com>
+pkgname=stegasoo-git
+pkgver=4.2.0.r0.g530e5de
+pkgrel=1
+pkgdesc="Secure steganography with hybrid photo + passphrase + PIN authentication"
+arch=('x86_64')
+url="https://github.com/adlee-was-taken/stegasoo"
+license=('MIT')
+
+# Python 3.11-3.14 supported (uses jpeglib for modern Python compatibility)
+depends=(
+    'python>=3.11'
+    'zbar'  # QR code reading for Web UI
+)
+makedepends=(
+    'git'
+    'python'
+    'python-build'
+    'python-hatchling'
+)
+provides=('stegasoo')
+conflicts=('stegasoo')
+install=stegasoo-git.install
+source=("${pkgname}::git+https://github.com/adlee-was-taken/stegasoo.git#branch=main")
+sha256sums=('SKIP')
+
+pkgver() {
+    cd "$pkgname"
+    git describe --long --tags 2>/dev/null | sed 's/^v//;s/\([^-]*-g\)/r\1/;s/-/./g' || \
+    printf "%s.r%s.g%s" "4.2.0" "$(git rev-list --count HEAD)" "$(git rev-parse --short HEAD)"
+}
+
+build() {
+    cd "$pkgname"
+    python -m build --wheel --no-isolation
+}
+
+package() {
+    cd "$pkgname"
+
+    # Detect Python version for site-packages path
+    local pyver=$(python -c 'import sys; print(f"{sys.version_info.major}.{sys.version_info.minor}")')
+
+    # Install to /opt/stegasoo with dedicated venv
+    install -dm755 "$pkgdir/opt/stegasoo"
+
+    # Create fresh venv in package
+    python -m venv "$pkgdir/opt/stegasoo/venv"
+
+    # Install the wheel with all extras
+    local wheel=$(ls dist/*.whl | head -1)
+    "$pkgdir/opt/stegasoo/venv/bin/pip" install --no-cache-dir "${wheel}[all]"
+
+    # Install frontends (not included in wheel)
+    local site_packages="$pkgdir/opt/stegasoo/venv/lib/python${pyver}/site-packages"
+    cp -r frontends "$site_packages/"
+
+    # Create writable directories for stegasoo user
+    install -dm755 "$pkgdir/opt/stegasoo/venv/var/app-instance"
+    install -dm755 "$site_packages/frontends/web/temp_files"
+    install -dm755 "$site_packages/frontends/api/temp_files"
+
+    # Fix shebangs - replace build-time paths with installed paths
+    find "$pkgdir/opt/stegasoo/venv/bin" -type f -exec \
+        sed -i "s|$pkgdir/opt/stegasoo/venv|/opt/stegasoo/venv|g" {} \;
+
+    # Fix pyvenv.cfg
+    sed -i "s|$pkgdir||g" "$pkgdir/opt/stegasoo/venv/pyvenv.cfg"
+
+    # Create symlinks to /usr/bin
+    install -dm755 "$pkgdir/usr/bin"
+    ln -s /opt/stegasoo/venv/bin/stegasoo "$pkgdir/usr/bin/stegasoo"
+
+    # Install license
+    install -Dm644 LICENSE "$pkgdir/usr/share/licenses/$pkgname/LICENSE"
+
+    # Install docs
+    install -Dm644 README.md "$pkgdir/usr/share/doc/$pkgname/README.md"
+
+    # Install systemd service files
+    install -Dm644 /dev/stdin "$pkgdir/usr/lib/systemd/system/stegasoo-web.service" <<EOF
+[Unit]
+Description=Stegasoo Web UI
+After=network.target
+
+[Service]
+Type=simple
+User=stegasoo
+WorkingDirectory=/opt/stegasoo/venv/lib/python${pyver}/site-packages/frontends/web
+Environment="PATH=/opt/stegasoo/venv/bin"
+ExecStart=/opt/stegasoo/venv/bin/gunicorn -b 127.0.0.1:5000 app:app
+Restart=on-failure
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+    install -Dm644 /dev/stdin "$pkgdir/usr/lib/systemd/system/stegasoo-api.service" <<EOF
+[Unit]
+Description=Stegasoo REST API
+After=network.target
+
+[Service]
+Type=simple
+User=stegasoo
+WorkingDirectory=/opt/stegasoo/venv/lib/python${pyver}/site-packages/frontends/api
+Environment="PATH=/opt/stegasoo/venv/bin"
+ExecStart=/opt/stegasoo/venv/bin/uvicorn main:app --host 127.0.0.1 --port 8000
+Restart=on-failure
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target
+EOF
+}

aur/README.md

@@ -0,0 +1,79 @@
+# Stegasoo AUR Package
+
+> **Note:** Uses Python 3.12 via `python312` AUR package (jpegio not yet compatible with 3.13)
+
+## Installation
+
+### From AUR (once published)
+```bash
+yay -S stegasoo-git
+# or
+paru -S stegasoo-git
+```
+
+### Manual build
+```bash
+git clone https://aur.archlinux.org/stegasoo-git.git
+cd stegasoo-git
+makepkg -si
+```
+
+## What Gets Installed
+
+- `/opt/stegasoo/venv/` - Self-contained Python 3.12 venv with all dependencies
+- `/usr/bin/stegasoo` - CLI symlink
+- `/usr/lib/systemd/system/stegasoo-web.service` - Web UI service
+- `/usr/lib/systemd/system/stegasoo-api.service` - REST API service
+
+## Optional Dependencies
+
+```bash
+# QR code reading from webcam/images
+sudo pacman -S zbar
+```
+
+All other dependencies are bundled in the venv.
+
+## Usage
+
+### CLI
+```bash
+stegasoo --help
+stegasoo generate --rsa --qr-ascii
+stegasoo encode -i carrier.jpg -r reference.jpg -m "secret" -P passphrase -p 123456
+```
+
+### Web UI (systemd)
+```bash
+# Create service user (first time)
+sudo useradd -r -s /usr/bin/nologin stegasoo
+
+# Start service
+sudo systemctl enable --now stegasoo-web
+
+# Access at http://localhost:5000
+```
+
+### REST API (systemd)
+```bash
+# Start service
+sudo systemctl enable --now stegasoo-api
+
+# Access at http://localhost:8000/docs
+```
+
+### Manual run (without systemd)
+```bash
+# Web UI
+/opt/stegasoo/venv/bin/python -m gunicorn -b 0.0.0.0:5000 \
+    --chdir /opt/stegasoo/venv/lib/python3.12/site-packages/frontends/web app:app
+
+# REST API
+/opt/stegasoo/venv/bin/uvicorn \
+    --app-dir /opt/stegasoo/venv/lib/python3.12/site-packages/frontends/api \
+    main:app --host 0.0.0.0 --port 8000
+```
+
+## Maintainer
+
+Aaron D. Lee

aur/stegasoo-git.install

@@ -0,0 +1,40 @@
+post_install() {
+    # Create stegasoo system user if it doesn't exist
+    if ! getent passwd stegasoo >/dev/null; then
+        useradd -r -s /usr/bin/nologin -d /opt/stegasoo stegasoo
+        echo "Created system user 'stegasoo'"
+    fi
+
+    # Set ownership of instance directory for Flask
+    chown -R stegasoo:stegasoo /opt/stegasoo/venv/var/app-instance 2>/dev/null || true
+
+    echo ""
+    echo "Stegasoo installed successfully!"
+    echo ""
+    echo "CLI usage:"
+    echo "  stegasoo --help"
+    echo ""
+    echo "To start the web UI:"
+    echo "  sudo systemctl start stegasoo-web"
+    echo ""
+    echo "To start the REST API:"
+    echo "  sudo systemctl start stegasoo-api"
+    echo ""
+}
+
+post_upgrade() {
+    post_install
+}
+
+pre_remove() {
+    # Stop services if running
+    systemctl stop stegasoo-web 2>/dev/null || true
+    systemctl stop stegasoo-api 2>/dev/null || true
+}
+
+post_remove() {
+    # Optionally remove the stegasoo user
+    # userdel stegasoo 2>/dev/null || true
+    echo "Stegasoo removed. User 'stegasoo' was not removed."
+    echo "To remove: userdel stegasoo"
+}

aur/test-build.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+# Test build the AUR package locally
+
+set -e
+
+cd "$(dirname "$0")"
+
+echo "=== Cleaning previous builds ==="
+rm -rf stegasoo-git pkg src *.pkg.tar.zst *.whl 2>/dev/null || true
+
+echo "=== Generating .SRCINFO ==="
+makepkg --printsrcinfo > .SRCINFO
+
+echo "=== Building package ==="
+makepkg -sf
+
+echo "=== Package built ==="
+ls -la *.pkg.tar.zst
+
+echo ""
+echo "To install: sudo pacman -U stegasoo-git-*.pkg.tar.zst"
+echo "To test:    makepkg -si"

docker/Dockerfile

@@ -35,12 +35,15 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     libzbar0 \
     libjpeg-dev \
     zlib1g-dev \
+    curl \
+    openssl \
     && rm -rf /var/lib/apt/lists/*
 
 # Install ALL dependencies (slow path)
 RUN pip install --no-cache-dir \
     cython numpy scipy>=1.10.0 jpegio>=0.2.0 \
     argon2-cffi>=23.0.0 pillow>=10.0.0 cryptography>=41.0.0 \
+    reedsolo>=1.7.0 \
     flask>=3.0.0 gunicorn>=21.0.0 \
     fastapi>=0.100.0 "uvicorn[standard]>=0.20.0" python-multipart>=0.0.6 \
     qrcode>=7.3.0 pyzbar>=0.1.9 click>=8.0.0 lz4>=4.0.0
@@ -57,6 +60,12 @@ FROM base AS web
 
 WORKDIR /app
 
+# Install runtime dependencies (curl for healthcheck, openssl for cert generation)
+USER root
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    curl openssl \
+    && rm -rf /var/lib/apt/lists/*
+
 # Copy application files (this is all that rebuilds normally!)
 COPY src/ src/
 COPY data/ data/
@@ -66,6 +75,10 @@ COPY frontends/web/ frontends/web/
 # temp_files is for multi-worker temp file sharing
 RUN mkdir -p /tmp/stego_uploads /app/frontends/web/instance /app/frontends/web/certs /app/frontends/web/temp_files
 
+# Copy and set up entrypoint (before switching to non-root user)
+COPY frontends/web/docker-entrypoint.sh /app/frontends/web/
+RUN chmod +x /app/frontends/web/docker-entrypoint.sh
+
 # Create non-root user
 RUN useradd -m -u 1000 stego && chown -R stego:stego /app /tmp/stego_uploads
 USER stego
@@ -77,12 +90,12 @@ ENV PYTHONPATH=/app/src
 EXPOSE 5000
 
 # Health check
-HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
-    CMD python -c "import urllib.request; urllib.request.urlopen('http://localhost:5000/')" || exit 1
+HEALTHCHECK --interval=30s --timeout=10s --start-period=10s --retries=3 \
+    CMD curl -fsk https://localhost:5000/ || curl -fs http://localhost:5000/ || exit 1
 
-# Run with gunicorn
+# Run with entrypoint (handles HTTPS/HTTP mode)
 WORKDIR /app/frontends/web
-CMD ["gunicorn", "--bind", "0.0.0.0:5000", "--workers", "2", "--threads", "4", "--timeout", "120", "app:app"]
+ENTRYPOINT ["/app/frontends/web/docker-entrypoint.sh"]
 
 # ============================================================================
 # API stage - REST API

docker/Dockerfile.base

@@ -32,7 +32,9 @@ RUN pip install --no-cache-dir \
     jpegio>=0.2.0 \
     argon2-cffi>=23.0.0 \
     pillow>=10.0.0 \
-    cryptography>=41.0.0
+    cryptography>=41.0.0 \
+    reedsolo>=1.7.0 \
+    zstandard>=0.22.0
 
 # Install web/api framework packages (also stable)
 RUN pip install --no-cache-dir \
@@ -47,9 +49,9 @@ RUN pip install --no-cache-dir \
     lz4>=4.0.0
 
 # Verify key packages work
-RUN python -c "import jpegio; import scipy; import numpy; print('jpegio + scipy + numpy OK')"
+RUN python -c "import jpegio; import scipy; import numpy; import zstandard; print('jpegio + scipy + numpy + zstd OK')"
 
 # Label for tracking
 LABEL org.opencontainers.image.title="Stegasoo Base"
 LABEL org.opencontainers.image.description="Pre-compiled dependencies for Stegasoo"
-LABEL org.opencontainers.image.version="4.0.0"
+LABEL org.opencontainers.image.version="4.2.0"

docker/docker-compose.yml

@@ -8,7 +8,8 @@ services:
   # ============================================================================
   web:
     build:
-      context: .
+      context: ..
+      dockerfile: docker/Dockerfile
       target: web
     container_name: stegasoo-web
     ports:
@@ -18,7 +19,9 @@ services:
       FLASK_ENV: production
       # Authentication (v4.0.2)
       STEGASOO_AUTH_ENABLED: ${STEGASOO_AUTH_ENABLED:-true}
-      STEGASOO_HTTPS_ENABLED: ${STEGASOO_HTTPS_ENABLED:-false}
+      # HTTPS enabled by default - generates self-signed cert if none provided
+      # To disable: STEGASOO_HTTPS_ENABLED=false docker-compose up
+      STEGASOO_HTTPS_ENABLED: ${STEGASOO_HTTPS_ENABLED:-true}
       STEGASOO_HOSTNAME: ${STEGASOO_HOSTNAME:-localhost}
     volumes:
       # Persist auth database and SSL certs (v4.0.2)
@@ -37,7 +40,8 @@ services:
   # ============================================================================
   api:
     build:
-      context: .
+      context: ..
+      dockerfile: docker/Dockerfile
       target: api
     container_name: stegasoo-api
     ports:

docs/DOCKER_QUICKSTART.md

@@ -0,0 +1,162 @@
+# Docker Quickstart
+
+Get Stegasoo running in Docker in under 5 minutes.
+
+## Build
+
+```bash
+# From project root:
+
+# Build web UI image
+sudo docker build -t stegasoo-web --target web -f docker/Dockerfile .
+
+# Or build all targets
+sudo docker build -t stegasoo-api --target api -f docker/Dockerfile .
+sudo docker build -t stegasoo-cli --target cli -f docker/Dockerfile .
+
+# Or use docker-compose
+sudo docker-compose -f docker/docker-compose.yml build
+```
+
+## Run (Basic)
+
+```bash
+# HTTP only, no auth
+sudo docker run -d \
+  -p 5000:5000 \
+  -e STEGASOO_AUTH_ENABLED=false \
+  --name stegasoo \
+  stegasoo-web
+```
+
+Visit http://localhost:5000
+
+## Run (Production)
+
+```bash
+# HTTPS + Auth + Channel Key
+sudo docker run -d \
+  -p 5000:5000 \
+  -e STEGASOO_AUTH_ENABLED=true \
+  -e STEGASOO_HTTPS_ENABLED=true \
+  -e STEGASOO_HOSTNAME=stegasoo.local \
+  -e STEGASOO_CHANNEL_KEY=ABCD-1234-EFGH-5678-IJKL-9012-MNOP-3456 \
+  -v stegasoo-data:/opt/stegasoo/frontends/web/instance \
+  -v stegasoo-certs:/opt/stegasoo/frontends/web/certs \
+  --name stegasoo \
+  stegasoo-web
+```
+
+Visit https://localhost:5000 (accept self-signed cert warning)
+
+## Environment Variables
+
+| Variable | Default | Description |
+|----------|---------|-------------|
+| `STEGASOO_AUTH_ENABLED` | `true` | Require login |
+| `STEGASOO_HTTPS_ENABLED` | `false` | Enable HTTPS |
+| `STEGASOO_HOSTNAME` | `localhost` | Hostname for SSL cert |
+| `STEGASOO_CHANNEL_KEY` | *(none)* | Shared channel key (32 alphanumeric chars with dashes) |
+
+## Docker Compose
+
+Create `.env` file in project root:
+```bash
+STEGASOO_AUTH_ENABLED=true
+STEGASOO_HTTPS_ENABLED=true
+STEGASOO_HOSTNAME=stegasoo.local
+STEGASOO_CHANNEL_KEY=
+```
+
+Run:
+```bash
+sudo docker-compose -f docker/docker-compose.yml up -d web
+```
+
+## Custom SSL Certificates
+
+### Use Your Own Certs
+
+```bash
+# Stop container
+sudo docker stop stegasoo
+
+# Copy certs to volume
+sudo docker run --rm -v stegasoo-certs:/certs -v $(pwd):/src alpine \
+  sh -c "cp /src/your-cert.crt /certs/server.crt && cp /src/your-key.key /certs/server.key && chmod 600 /certs/server.key"
+
+# Start container
+sudo docker start stegasoo
+```
+
+### Use mkcert (Local Development)
+
+```bash
+# Install mkcert
+brew install mkcert  # macOS
+# or: sudo apt install mkcert  # Debian/Ubuntu
+
+# Create local CA and certs
+mkcert -install
+mkcert -cert-file server.crt -key-file server.key localhost 127.0.0.1 stegasoo.local
+
+# Copy to Docker volume (see above)
+```
+
+### Use Let's Encrypt (Public Server)
+
+```bash
+# Get cert
+sudo certbot certonly --standalone -d yourdomain.com
+
+# Copy to Docker volume
+sudo docker run --rm -v stegasoo-certs:/certs alpine \
+  sh -c "cp /etc/letsencrypt/live/yourdomain.com/fullchain.pem /certs/server.crt && \
+         cp /etc/letsencrypt/live/yourdomain.com/privkey.pem /certs/server.key && \
+         chmod 600 /certs/server.key"
+```
+
+## Volumes
+
+| Volume | Purpose |
+|--------|---------|
+| `stegasoo-data` | User database, settings |
+| `stegasoo-certs` | SSL certificates |
+
+## Smoke Test
+
+```bash
+# Check container logs
+sudo docker logs stegasoo
+
+# Test HTTP endpoint
+curl -k https://localhost:5000/health
+
+# Expected: {"status":"ok","version":"4.1.7",...}
+```
+
+## Troubleshooting
+
+**Container won't start:**
+```bash
+sudo docker logs stegasoo
+```
+
+**Out of memory:**
+```bash
+# Argon2 needs 256MB+ per operation
+sudo docker run --memory=768m ...
+```
+
+**Certificate errors:**
+```bash
+# Regenerate self-signed cert
+sudo docker exec stegasoo rm -rf /opt/stegasoo/frontends/web/certs/*
+sudo docker restart stegasoo
+```
+
+**Reset everything:**
+```bash
+sudo docker stop stegasoo && sudo docker rm stegasoo
+sudo docker volume rm stegasoo-data stegasoo-certs
+```

docs/TEMPLATES.md

@@ -126,7 +126,7 @@ Quick reference for all Jinja2 templates in `frontends/web/templates/`.
 - `use_pin` - checkbox
 - `pin_length` - PIN digits (6-9)
 - `use_rsa` - checkbox
-- `rsa_bits` - key size (2048/3072/4096)
+- `rsa_bits` - key size (2048/3072)
 
 **Output panels:**
 - Passphrase display

docs/stegasoo.1

@@ -0,0 +1,340 @@
+.\" Stegasoo man page
+.\" Generate with: groff -man -Tascii stegasoo.1
+.TH STEGASOO 1 "January 2026" "Stegasoo 4.1.7" "User Commands"
+.SH NAME
+stegasoo \- steganography with hybrid authentication
+.SH SYNOPSIS
+.B stegasoo
+[\fB\-v\fR|\fB\-\-version\fR]
+[\fB\-\-json\fR]
+[\fB\-h\fR|\fB\-\-help\fR]
+.I command
+[\fIargs\fR]
+.SH DESCRIPTION
+.B stegasoo
+hides messages and files in images using PIN + passphrase security.
+It uses LSB (Least Significant Bit) steganography with optional DCT
+(Discrete Cosine Transform) encoding for JPEG resilience.
+.PP
+Messages are encrypted using a hybrid authentication scheme that combines
+a reference photo (shared secret), passphrase, and PIN code.
+.SH GLOBAL OPTIONS
+.TP
+.BR \-v ", " \-\-version
+Show version and exit.
+.TP
+.B \-\-json
+Output results as JSON (where supported).
+.TP
+.BR \-h ", " \-\-help
+Show help message and exit.
+.SH COMMANDS
+.SS encode
+Encode a message or file into an image.
+.PP
+.B stegasoo encode
+.I carrier
+.B \-r
+.I reference
+[\fB\-m\fR \fImessage\fR | \fB\-f\fR \fIfile\fR]
+[\fIoptions\fR]
+.TP
+.BR \-r ", " \-\-reference " " \fIPATH\fR
+Reference photo (shared secret). Required.
+.TP
+.BR \-m ", " \-\-message " " \fITEXT\fR
+Message to encode.
+.TP
+.BR \-f ", " \-\-file " " \fIPATH\fR
+File to embed instead of message.
+.TP
+.BR \-o ", " \-\-output " " \fIPATH\fR
+Output image path.
+.TP
+.B \-\-passphrase " " \fITEXT\fR
+Passphrase (recommend 4+ words). Prompts if not provided.
+.TP
+.B \-\-pin " " \fITEXT\fR
+PIN code. Prompts if not provided.
+.TP
+.B \-\-dry\-run
+Show capacity usage without encoding.
+.PP
+.B Examples:
+.nf
+    stegasoo encode photo.png -r ref.jpg -m "Secret" --passphrase --pin
+    stegasoo encode photo.png -r ref.jpg -f doc.pdf -o encoded.png
+.fi
+.SS decode
+Decode a message or file from an image.
+.PP
+.B stegasoo decode
+.I image
+.B \-r
+.I reference
+[\fIoptions\fR]
+.TP
+.BR \-r ", " \-\-reference " " \fIPATH\fR
+Reference photo (shared secret). Required.
+.TP
+.B \-\-passphrase " " \fITEXT\fR
+Passphrase. Prompts if not provided.
+.TP
+.B \-\-pin " " \fITEXT\fR
+PIN code. Prompts if not provided.
+.TP
+.BR \-o ", " \-\-output " " \fIPATH\fR
+Output path for file payloads.
+.PP
+.B Examples:
+.nf
+    stegasoo decode encoded.png -r ref.jpg --passphrase --pin
+    stegasoo decode encoded.png -r ref.jpg -o ./extracted/
+.fi
+.SS generate
+Generate random credentials (passphrase + PIN + optional channel key).
+.PP
+.B stegasoo generate
+[\fIoptions\fR]
+.TP
+.B \-\-words " " \fIINTEGER\fR
+Number of words in passphrase (default: 4).
+.TP
+.B \-\-pin\-length " " \fIINTEGER\fR
+PIN length (default: 6).
+.TP
+.B \-\-channel\-key
+Also generate a 256-bit channel key.
+.PP
+.B Examples:
+.nf
+    stegasoo generate
+    stegasoo generate --words 6 --pin-length 8
+    stegasoo generate --channel-key
+.fi
+.SS info
+Show version, features, and system information.
+.PP
+.B stegasoo info
+[\fB\-\-full\fR]
+.TP
+.B \-\-full
+Show full system information (CPU, temperature, disk on Pi).
+.SS batch
+Batch operations on multiple images.
+.PP
+.B stegasoo batch
+.I subcommand
+[\fIargs\fR]
+.TP
+.B batch encode
+Encode message into multiple images.
+.RS
+.PP
+.B stegasoo batch encode
+.I images...
+[\fB\-m\fR \fImessage\fR | \fB\-f\fR \fIfile\fR]
+[\fIoptions\fR]
+.PP
+Options: \fB\-m\fR, \fB\-f\fR, \fB\-o\fR/\fB\-\-output\-dir\fR, \fB\-\-suffix\fR, \fB\-\-passphrase\fR, \fB\-\-pin\fR,
+\fB\-r\fR/\fB\-\-recursive\fR, \fB\-j\fR/\fB\-\-jobs\fR, \fB\-v\fR/\fB\-\-verbose\fR.
+.RE
+.TP
+.B batch decode
+Decode messages from multiple images.
+.RS
+.PP
+.B stegasoo batch decode
+.I images...
+[\fIoptions\fR]
+.PP
+Options: \fB\-o\fR/\fB\-\-output\-dir\fR, \fB\-\-passphrase\fR, \fB\-\-pin\fR, \fB\-r\fR/\fB\-\-recursive\fR,
+\fB\-j\fR/\fB\-\-jobs\fR, \fB\-v\fR/\fB\-\-verbose\fR.
+.RE
+.TP
+.B batch check
+Check capacity of multiple images.
+.RS
+.PP
+.B stegasoo batch check
+.I images...
+[\fB\-r\fR/\fB\-\-recursive\fR]
+.RE
+.SS channel
+Manage channel keys for deployment isolation.
+.PP
+Channel keys bind encode/decode operations to a specific group or deployment.
+Messages encoded with one channel key can only be decoded by systems with
+the same channel key.
+.PP
+.B stegasoo channel
+.I subcommand
+[\fIargs\fR]
+.TP
+.B channel generate
+Generate a new random channel key.
+.RS
+.PP
+Options: \fB\-\-save\fR (project config), \fB\-\-save\-user\fR (user config).
+.RE
+.TP
+.B channel show
+Show the current channel key.
+.RS
+.PP
+Options: \fB\-\-key\fR \fITEXT\fR (show specific key instead).
+.RE
+.TP
+.B channel qr
+Display channel key as QR code.
+.RS
+.PP
+Options: \fB\-\-key\fR \fITEXT\fR, \fB\-\-format\fR [\fIascii\fR|\fIpng\fR], \fB\-o\fR/\fB\-\-output\fR \fIPATH\fR.
+.RE
+.TP
+.B channel status
+Show channel key status and configuration.
+.TP
+.B channel clear
+Remove channel key configuration.
+.RS
+.PP
+Options: \fB\-\-project\fR, \fB\-\-user\fR.
+.RE
+.SS admin
+Web UI administration commands.
+.PP
+.B stegasoo admin
+.I subcommand
+[\fIargs\fR]
+.TP
+.B admin generate\-key
+Generate a new recovery key (for reference only).
+.RS
+.PP
+Options: \fB\-\-qr\fR (show QR code in terminal).
+.RE
+.TP
+.B admin recover
+Reset admin password using recovery key.
+.RS
+.PP
+Options: \fB\-\-db\fR \fIPATH\fR (path to stegasoo.db), \fB\-\-password\fR \fITEXT\fR.
+.RE
+.SS tools
+Image security tools.
+.PP
+.B stegasoo tools
+.I subcommand
+[\fIargs\fR]
+.TP
+.B tools capacity
+Show steganography capacity for an image.
+.RS
+.PP
+.B stegasoo tools capacity
+.I image
+[\fB\-\-json\fR]
+.RE
+.TP
+.B tools exif
+View or edit EXIF metadata.
+.RS
+.PP
+.B stegasoo tools exif
+.I image
+[\fB\-\-clear\fR] [\fB\-\-set\fR \fIFIELD=VALUE\fR] [\fB\-o\fR \fIPATH\fR] [\fB\-\-json\fR]
+.RE
+.TP
+.B tools peek
+Check if image contains Stegasoo hidden data.
+.RS
+.PP
+.B stegasoo tools peek
+.I image
+[\fB\-\-json\fR]
+.RE
+.TP
+.B tools strip
+Strip EXIF/metadata from an image.
+.RS
+.PP
+.B stegasoo tools strip
+.I image
+[\fB\-o\fR \fIPATH\fR] [\fB\-\-format\fR [\fIpng\fR|\fIbmp\fR]]
+.RE
+.SH ENVIRONMENT
+.TP
+.B STEGASOO_CHANNEL_KEY
+Channel key for encode/decode operations. Overrides config file settings.
+.TP
+.B STEGASOO_HTTPS_ENABLED
+Enable HTTPS for web UI (Docker/service mode).
+.TP
+.B STEGASOO_HOSTNAME
+Hostname for SSL certificate generation.
+.SH FILES
+.TP
+.I ~/.stegasoo/channel.key
+User's channel key configuration (encrypted).
+.TP
+.I .stegasoo.toml
+Project-level configuration file.
+.TP
+.I frontends/web/instance/stegasoo.db
+Web UI SQLite database (accounts, settings).
+.SH EXAMPLES
+.SS Basic encode/decode workflow
+.nf
+# Generate credentials
+stegasoo generate
+
+# Encode a secret message
+stegasoo encode vacation.png -r selfie.jpg -m "Meet at noon"
+
+# Decode the message (on another system with same reference photo)
+stegasoo decode vacation_steg.png -r selfie.jpg
+.fi
+.SS Using channel keys for team isolation
+.nf
+# Generate and save a channel key
+stegasoo channel generate --save-user
+
+# Share the key with your team
+stegasoo channel qr -o team-key.png
+
+# Now all encode/decode operations use this channel
+stegasoo encode photo.png -r ref.jpg -m "Team secret"
+.fi
+.SS Batch processing
+.nf
+# Check capacity of all PNGs in a directory
+stegasoo batch check ./photos/*.png
+
+# Encode same message into multiple images
+stegasoo batch encode ./photos/ -r ref.jpg -m "Secret" -o ./encoded/
+.fi
+.SH SECURITY
+Stegasoo uses multiple layers of security:
+.IP \(bu 2
+Reference photo provides a visual shared secret
+.IP \(bu 2
+Passphrase (recommend 4+ words) for strong encryption
+.IP \(bu 2
+PIN code adds additional entropy
+.IP \(bu 2
+Channel keys isolate different deployments
+.IP \(bu 2
+AES-256 encryption for payload data
+.PP
+For maximum security, share the reference photo out-of-band (in person,
+secure messenger) and use a strong passphrase.
+.SH SEE ALSO
+.BR openssl (1),
+.BR qrencode (1)
+.SH BUGS
+Report bugs at: https://github.com/adlee-was-taken/stegasoo/issues
+.SH AUTHOR
+Written by the Stegasoo contributors.
+.SH COPYRIGHT
+Copyright \(co 2024-2026. MIT License.

frontends/api/main.py

@@ -1,10 +1,14 @@
 #!/usr/bin/env python3
 """
-Stegasoo REST API (v4.0.0)
+Stegasoo REST API (v4.2.0)
 
 FastAPI-based REST API for steganography operations.
 Supports both text messages and file embedding.
 
+CHANGES in v4.2.0:
+- Async encode/decode operations (run in thread pool)
+- Server can handle concurrent requests without blocking
+
 CHANGES in v4.0.0:
 - Added channel key support for deployment/group isolation
 - New /channel endpoints for key management
@@ -21,8 +25,10 @@ NEW in v3.0: LSB and DCT embedding modes.
 NEW in v3.0.1: DCT color mode and JPEG output format.
 """
 
+import asyncio
 import base64
 import sys
+from functools import partial
 from pathlib import Path
 from typing import Literal
 
@@ -68,13 +74,20 @@ from stegasoo.constants import (
 try:
     from stegasoo.qr_utils import (
         extract_key_from_qr,
+        generate_qr_ascii,
+        generate_qr_code,
         has_qr_read,
+        has_qr_write,
     )
 
     HAS_QR_READ = has_qr_read()
+    HAS_QR_WRITE = has_qr_write()
 except ImportError:
     HAS_QR_READ = False
+    HAS_QR_WRITE = False
     extract_key_from_qr = None
+    generate_qr_code = None
+    generate_qr_ascii = None
 
 
 # ============================================================================
@@ -357,6 +370,7 @@ class StatusResponse(BaseModel):
     version: str
     has_argon2: bool
     has_qrcode_read: bool
+    has_qrcode_write: bool  # v4.2.0: QR generation capability
     has_dct: bool
     max_payload_kb: int
     available_modes: list[str]
@@ -372,6 +386,32 @@ class QrExtractResponse(BaseModel):
     error: str | None = None
 
 
+class QrGenerateRequest(BaseModel):
+    """Request to generate QR code from RSA key."""
+
+    key_pem: str = Field(..., description="RSA private key in PEM format")
+    output_format: str = Field(
+        default="png",
+        description="Output format: 'png', 'jpg', or 'ascii'",
+    )
+    compress: bool = Field(
+        default=True,
+        description="Compress key data with zstd (recommended for larger keys)",
+    )
+
+
+class QrGenerateResponse(BaseModel):
+    """Response containing generated QR code."""
+
+    success: bool
+    format: str | None = None
+    qr_data: str | None = Field(
+        default=None,
+        description="Base64-encoded image data (for png/jpg) or ASCII string",
+    )
+    error: str | None = None
+
+
 class WillFitRequest(BaseModel):
     """Request to check if payload will fit."""
 
@@ -436,6 +476,27 @@ def _get_channel_info(channel_key: str | None) -> tuple[str, str | None]:
     return info["mode"], info.get("fingerprint")
 
 
+# ============================================================================
+# HELPER: ASYNC EXECUTION
+# ============================================================================
+
+
+async def run_in_thread(func, *args, **kwargs):
+    """
+    Run a CPU-bound function in a thread pool.
+
+    This allows the FastAPI server to handle other requests while
+    encode/decode operations are running. Essential for Pi deployments
+    where operations can take several seconds.
+
+    Usage:
+        result = await run_in_thread(encode, message=msg, carrier_image=carrier, ...)
+    """
+    if kwargs:
+        func = partial(func, **kwargs)
+    return await asyncio.to_thread(func, *args)
+
+
 # ============================================================================
 # ROUTES - STATUS & INFO
 # ============================================================================
@@ -469,6 +530,7 @@ async def root():
         version=__version__,
         has_argon2=has_argon2(),
         has_qrcode_read=HAS_QR_READ,
+        has_qrcode_write=HAS_QR_WRITE,
         has_dct=has_dct_support(),
         max_payload_kb=MAX_FILE_PAYLOAD_SIZE // 1024,
         available_modes=available_modes,
@@ -760,6 +822,51 @@ async def api_extract_key_from_qr(
         return QrExtractResponse(success=False, error=str(e))
 
 
+@app.post("/generate-key-qr", response_model=QrGenerateResponse)
+async def api_generate_key_qr(request: QrGenerateRequest):
+    """
+    Generate QR code from an RSA private key.
+
+    Supports PNG, JPG, and ASCII output formats.
+    Uses zstd compression by default for better QR code density.
+    """
+    if not HAS_QR_WRITE:
+        raise HTTPException(501, "QR code generation not available. Install qrcode library.")
+
+    try:
+        fmt = request.output_format.lower()
+
+        if fmt == "ascii":
+            ascii_qr = generate_qr_ascii(
+                request.key_pem,
+                compress=request.compress,
+                invert=False,
+            )
+            return QrGenerateResponse(success=True, format="ascii", qr_data=ascii_qr)
+
+        elif fmt in ("png", "jpg", "jpeg"):
+            import base64
+
+            qr_bytes = generate_qr_code(
+                request.key_pem,
+                compress=request.compress,
+                output_format=fmt,
+            )
+            qr_b64 = base64.b64encode(qr_bytes).decode("ascii")
+            return QrGenerateResponse(success=True, format=fmt, qr_data=qr_b64)
+
+        else:
+            return QrGenerateResponse(
+                success=False,
+                error=f"Unsupported format: {fmt}. Use 'png', 'jpg', or 'ascii'",
+            )
+
+    except ValueError as e:
+        return QrGenerateResponse(success=False, error=str(e))
+    except Exception as e:
+        return QrGenerateResponse(success=False, error=f"QR generation failed: {e}")
+
+
 # ============================================================================
 # ROUTES - GENERATE
 # ============================================================================
@@ -874,8 +981,9 @@ async def api_encode(request: EncodeRequest):
             request.embed_mode, request.dct_output_format, request.dct_color_mode
         )
 
-        # v4.0.0: Include channel_key
-        result = encode(
+        # v4.2.0: Run CPU-bound encode in thread pool
+        result = await run_in_thread(
+            encode,
             message=request.message,
             reference_photo=ref_photo,
             carrier_image=carrier,
@@ -950,8 +1058,9 @@ async def api_encode_file(request: EncodeFileRequest):
             request.embed_mode, request.dct_output_format, request.dct_color_mode
         )
 
-        # v4.0.0: Include channel_key
-        result = encode(
+        # v4.2.0: Run CPU-bound encode in thread pool
+        result = await run_in_thread(
+            encode,
             message=payload,
             reference_photo=ref_photo,
             carrier_image=carrier,
@@ -1021,8 +1130,9 @@ async def api_decode(request: DecodeRequest):
         ref_photo = base64.b64decode(request.reference_photo_base64)
         rsa_key = base64.b64decode(request.rsa_key_base64) if request.rsa_key_base64 else None
 
-        # v4.0.0: Include channel_key
-        result = decode(
+        # v4.2.0: Run CPU-bound decode in thread pool
+        result = await run_in_thread(
+            decode,
             stego_image=stego,
             reference_photo=ref_photo,
             passphrase=request.passphrase,
@@ -1150,8 +1260,9 @@ async def api_encode_multipart(
         # Get DCT parameters
         dct_params = _get_dct_params(embed_mode, dct_output_format, dct_color_mode)
 
-        # v4.0.0: Include channel_key
-        result = encode(
+        # v4.2.0: Run CPU-bound encode in thread pool
+        result = await run_in_thread(
+            encode,
             message=payload,
             reference_photo=ref_data,
             carrier_image=carrier_data,
@@ -1264,8 +1375,9 @@ async def api_decode_multipart(
         # QR code keys are never password-protected
         effective_password = None if rsa_key_from_qr else (rsa_password if rsa_password else None)
 
-        # v4.0.0: Include channel_key
-        result = decode(
+        # v4.2.0: Run CPU-bound decode in thread pool
+        result = await run_in_thread(
+            decode,
             stego_image=stego_data,
             reference_photo=ref_data,
             passphrase=passphrase,

frontends/cli/main.py

@@ -120,6 +120,7 @@ try:
     from stegasoo.qr_utils import (  # noqa: F401
         can_fit_in_qr,
         extract_key_from_qr_file,
+        generate_qr_ascii,
         generate_qr_code,
         has_qr_read,
         has_qr_write,
@@ -136,6 +137,9 @@ except ImportError:
     def has_qr_write() -> bool:
         return False
 
+    def generate_qr_ascii(*args, **kwargs):
+        raise RuntimeError("QR code generation not available")
+
 
 # ============================================================================
 # CLI SETUP
@@ -236,7 +240,7 @@ def format_channel_status_line(quiet: bool = False) -> str | None:
     help=f"PIN length (6-9, default: {DEFAULT_PIN_LENGTH})",
 )
 @click.option(
-    "--rsa-bits", type=click.Choice(["2048", "3072", "4096"]), default="2048", help="RSA key size"
+    "--rsa-bits", type=click.Choice(["2048", "3072"]), default="2048", help="RSA key size"
 )
 @click.option(
     "--words",
@@ -247,7 +251,13 @@ def format_channel_status_line(quiet: bool = False) -> str | None:
 @click.option("--output", "-o", type=click.Path(), help="Save RSA key to file (requires password)")
 @click.option("--password", "-p", help="Password for RSA key file")
 @click.option("--json", "as_json", is_flag=True, help="Output as JSON")
-def generate(pin, rsa, pin_length, rsa_bits, words, output, password, as_json):
+@click.option(
+    "--qr",
+    type=click.Path(),
+    help="Save RSA key QR code to file (png/jpg, uses zstd compression)",
+)
+@click.option("--qr-ascii", is_flag=True, help="Print RSA key as ASCII QR code to terminal")
+def generate(pin, rsa, pin_length, rsa_bits, words, output, password, as_json, qr, qr_ascii):
     """
     Generate credentials for encoding/decoding.
 
@@ -261,13 +271,18 @@ def generate(pin, rsa, pin_length, rsa_bits, words, output, password, as_json):
     Examples:
         stegasoo generate
         stegasoo generate --words 5
-        stegasoo generate --rsa --rsa-bits 4096
+        stegasoo generate --rsa --rsa-bits 3072
         stegasoo generate --rsa -o mykey.pem -p "secretpassword"
+        stegasoo generate --rsa --qr key.png
+        stegasoo generate --rsa --qr-ascii
         stegasoo generate --no-pin --rsa
     """
     if not pin and not rsa:
         raise click.UsageError("Must enable at least one of --pin or --rsa")
 
+    if (qr or qr_ascii) and not rsa:
+        raise click.UsageError("QR output requires --rsa to generate an RSA key")
+
     if output and not password:
         raise click.UsageError("--password is required when saving RSA key to file")
 
@@ -334,6 +349,33 @@ def generate(pin, rsa, pin_length, rsa_bits, words, output, password, as_json):
                 click.echo(creds.rsa_key_pem)
             click.echo()
 
+            # QR code output (v4.2.0)
+            if qr:
+                if not HAS_QR:
+                    click.secho("    ⚠️  QR code library not available", fg="yellow")
+                else:
+                    # Determine format from extension
+                    qr_path = Path(qr)
+                    ext = qr_path.suffix.lower()
+                    fmt = "jpeg" if ext in (".jpg", ".jpeg") else "png"
+
+                    qr_bytes = generate_qr_code(creds.rsa_key_pem, compress=True, output_format=fmt)
+                    qr_path.write_bytes(qr_bytes)
+                    click.secho(f"─── RSA KEY QR CODE ───", fg="green")
+                    click.secho(f"    Saved to: {qr}", fg="bright_white")
+                    click.secho("    ⚠️  Contains unencrypted private key!", fg="yellow")
+                    click.echo()
+
+            if qr_ascii:
+                if not HAS_QR:
+                    click.secho("    ⚠️  QR code library not available", fg="yellow")
+                else:
+                    click.secho("─── RSA KEY QR CODE (ASCII) ───", fg="green")
+                    click.secho("    ⚠️  Contains unencrypted private key!", fg="yellow")
+                    click.echo()
+                    ascii_qr = generate_qr_ascii(creds.rsa_key_pem, compress=True, invert=True)
+                    click.echo(ascii_qr)
+
         click.secho("─── SECURITY ───", fg="green")
         click.echo(f"    Passphrase entropy: {creds.passphrase_entropy} bits ({words} words)")
         if creds.pin:

frontends/web/app.py

@@ -2,23 +2,76 @@
 """
 Stegasoo Web Frontend (v4.0.0)
 
-Flask-based web UI for steganography operations.
-Supports both text messages and file embedding.
+A production Flask application demonstrating proper web architecture patterns.
+This isn't just a quick demo - it's built to run on a Raspberry Pi 24/7.
+
+ARCHITECTURE OVERVIEW
+=====================
+
+    ┌─────────────────────────────────────────────────────────────────────┐
+    │                         FLASK APPLICATION                            │
+    ├─────────────────────────────────────────────────────────────────────┤
+    │                                                                      │
+    │   Routes (/encode, /decode, /api/*)                                  │
+    │       │                                                              │
+    │       ├── auth.py           # Session management, user accounts      │
+    │       ├── temp_storage.py   # File-based temp storage with expiry    │
+    │       ├── subprocess_stego.py  # Isolated encode/decode workers      │
+    │       └── ssl_utils.py      # Self-signed cert generation            │
+    │                                                                      │
+    │   Templates (Jinja2)                                                 │
+    │       └── base.html → encode.html, decode.html, etc.                │
+    │                                                                      │
+    │   Static assets (CSS, JS)                                           │
+    │       └── Vanilla JS, no framework (keeps it simple)                │
+    │                                                                      │
+    └─────────────────────────────────────────────────────────────────────┘
+
+KEY PATTERNS
+============
+
+1. SUBPROCESS ISOLATION
+   Stegasoo's DCT mode uses scipy/jpeglib which can crash on malformed input.
+   We run encode/decode in subprocesses so crashes don't take down the server:
+
+       subprocess_stego = SubprocessStego(timeout=180)
+       result = subprocess_stego.encode(carrier, ref, message, ...)
+
+   If the subprocess crashes, we catch it and return an error gracefully.
+
+2. ASYNC JOBS WITH PROGRESS
+   Encoding large images can take 30+ seconds. We use ThreadPoolExecutor
+   to run jobs in background threads with progress reporting:
+
+       job_id = generate_job_id()
+       _executor.submit(_run_encode_job, job_id, params)
+       # Client polls /api/encode/progress/<job_id> for updates
+
+3. CONTEXT PROCESSORS
+   @app.context_processor injects variables into ALL templates:
+
+       return {"version": __version__, "has_dct": has_dct_support()}
+
+   Now every template can use {{ version }} without passing it explicitly.
+
+4. BEFORE_REQUEST HOOKS
+   @app.before_request runs before every request. We use it for:
+   - First-run setup redirect (no users → /setup)
+   - Session validation
+   - Cleanup of old temp files
+
+5. SECURE SECRET KEY
+   Flask sessions need a secret key. We persist it to a file so sessions
+   survive server restarts (otherwise everyone gets logged out).
 
 CHANGES in v4.0.0:
 - Added channel key support for deployment/group isolation
 - New /api/channel/status endpoint
 - Channel key selector on encode/decode pages
-- Messages encoded with channel key require same key to decode
 
 CHANGES in v3.2.0:
 - Removed date dependency from all operations
-- Renamed day_phrase → passphrase
-- No date selection or tracking needed
 - Simplified user experience for asynchronous communications
-
-NEW in v3.0: LSB and DCT embedding modes with advanced options.
-NEW in v3.0.1: DCT output format selection (PNG or JPEG) and color mode (grayscale or color).
 """
 
 import io
@@ -31,6 +84,7 @@ import time
 from concurrent.futures import ThreadPoolExecutor
 from pathlib import Path
 
+import temp_storage
 from auth import (
     MAX_CHANNEL_KEYS,
     MAX_USERS,
@@ -83,7 +137,6 @@ from flask import (
 )
 from PIL import Image
 from ssl_utils import ensure_certs
-import temp_storage
 
 os.environ["NUMPY_MADVISE_HUGEPAGE"] = "0"
 os.environ["OMP_NUM_THREADS"] = "1"
@@ -157,8 +210,35 @@ except ImportError:
 # ============================================================================
 # SUBPROCESS ISOLATION FOR STEGASOO OPERATIONS
 # ============================================================================
-# Runs encode/decode/compare in subprocesses to prevent jpegio/scipy crashes
-# from taking down the Flask server.
+#
+# This is a critical reliability pattern. Here's the problem:
+#
+# scipy's DCT and jpeglib can crash (segfault) on:
+# - Malformed JPEG files
+# - Very large images that exhaust memory
+# - Certain edge cases in coefficient manipulation
+#
+# If these crash in the main Flask process, your whole server dies.
+# Users get a connection reset, and the service goes down.
+#
+# The solution: Run stegasoo operations in separate Python processes.
+#
+#     Main Flask process                 Worker subprocess
+#     ┌─────────────────┐               ┌─────────────────┐
+#     │                 │   spawn       │                 │
+#     │  /api/encode    │──────────────>│  encode()       │
+#     │                 │               │                 │
+#     │  wait for       │<──────────────│  return result  │
+#     │  result         │    or crash   │  (or crash)     │
+#     │                 │               │                 │
+#     │  handle error   │               │  (process dies) │
+#     └─────────────────┘               └─────────────────┘
+#
+# If the subprocess crashes, we catch the error and return a friendly message.
+# The main server keeps running. Users can try again with different input.
+#
+# The subprocess_stego module handles all the pickling/unpickling of data.
+
 from subprocess_stego import (
     SubprocessStego,
     cleanup_progress_file,
@@ -169,9 +249,11 @@ from subprocess_stego import (
 
 from stegasoo.qr_utils import (
     can_fit_in_qr,
+    decompress_data,
     detect_and_crop_qr,
     extract_key_from_qr,
     generate_qr_code,
+    is_compressed,
 )
 
 # Initialize subprocess wrapper (worker script must be in same directory)
@@ -181,38 +263,89 @@ subprocess_stego = SubprocessStego(timeout=180)  # 3 minute timeout for large im
 # ============================================================================
 # FLASK APP CONFIGURATION
 # ============================================================================
+#
+# Flask configuration demonstrates several production patterns:
+#
+# 1. SECRET KEY PERSISTENCE
+#    Flask uses secret_key to sign session cookies. If it changes, all users
+#    get logged out. We save it to a file so it survives restarts.
+#
+# 2. CONTENT LENGTH LIMITS
+#    MAX_CONTENT_LENGTH prevents DoS via huge uploads. Flask will reject
+#    requests that exceed this before loading them into memory.
+#
+# 3. ENVIRONMENT-BASED CONFIG
+#    Settings come from environment variables, allowing:
+#    - Different settings per deployment (dev/staging/prod)
+#    - Docker/systemd to inject config without code changes
+#    - 12-factor app compliance
+#
+# 4. INSTANCE FOLDER
+#    Flask's instance_path is for per-deployment data (databases, keys).
+#    It's .gitignored by default - perfect for secrets.
 
 app = Flask(__name__)
 
 # Persist secret key so sessions survive restarts
+# Without this, every restart = everyone gets logged out
 _instance_path = Path(app.instance_path)
 _instance_path.mkdir(parents=True, exist_ok=True)
 _secret_key_file = _instance_path / ".secret_key"
 if _secret_key_file.exists():
     app.secret_key = _secret_key_file.read_text().strip()
 else:
-    app.secret_key = secrets.token_hex(32)
+    # First run: generate a new key and save it
+    app.secret_key = secrets.token_hex(32)  # 256 bits of randomness
     _secret_key_file.write_text(app.secret_key)
-    _secret_key_file.chmod(0o600)
+    _secret_key_file.chmod(0o600)  # Only owner can read
 
+# Reject uploads larger than this (prevents memory exhaustion)
 app.config["MAX_CONTENT_LENGTH"] = MAX_FILE_SIZE
 
 # Auth configuration from environment
+# STEGASOO_AUTH_ENABLED=false disables login (for local/dev use)
 app.config["AUTH_ENABLED"] = os.environ.get("STEGASOO_AUTH_ENABLED", "true").lower() == "true"
 app.config["HTTPS_ENABLED"] = os.environ.get("STEGASOO_HTTPS_ENABLED", "false").lower() == "true"
 
-# Initialize auth module
+# Initialize auth module (sets up session handling, user DB)
 init_auth(app)
 
 # ============================================================================
 # ASYNC JOB MANAGEMENT (v4.1.2)
 # ============================================================================
-# Encode operations can run in background threads with progress reporting
+#
+# Problem: DCT encoding a large image can take 30-60 seconds.
+# Solution: Run it in a background thread, let the client poll for progress.
+#
+# The flow:
+#
+#     Client                          Server
+#     ──────                          ──────
+#     POST /api/encode/async ──────>  Start background job
+#                            <──────  Return job_id
+#
+#     GET /api/encode/progress/123 ─>  Check job status
+#                            <──────  {"progress": 45, "phase": "embedding"}
+#
+#     GET /api/encode/progress/123 ─>  Check again
+#                            <──────  {"status": "complete", "file_id": "abc"}
+#
+#     GET /api/download/abc ────────>  Download result
+#                            <──────  Encoded image
+#
+# Why ThreadPoolExecutor instead of Celery/Redis?
+# - This runs on a Raspberry Pi with 1GB RAM
+# - We don't need distributed workers
+# - Keep it simple - threads are fine for 2 concurrent jobs
+#
+# The thread pool is limited to 2 workers because:
+# - Each encode loads the full image into memory
+# - Too many concurrent jobs = OOM on the Pi
 
-# Thread pool for background encode/decode operations
 _executor = ThreadPoolExecutor(max_workers=2)
 
-# Job storage: job_id -> {status, result, error, file_id, ...}
+# Job storage: job_id -> {status, result, error, file_id, created, ...}
+# We use a dict with a lock because threads access it concurrently
 _jobs = {}
 _jobs_lock = threading.Lock()
 
@@ -267,6 +400,27 @@ THUMBNAIL_FILES: dict[str, bytes] = {}  # Not used - see temp_storage.py
 # ============================================================================
 # TEMPLATE CONTEXT PROCESSOR
 # ============================================================================
+#
+# Context processors inject variables into EVERY template automatically.
+# Instead of passing the same data to every render_template() call:
+#
+#     # Bad: repetitive and error-prone
+#     return render_template("page.html", version=__version__, has_dct=...)
+#
+# We define it once here and it's available everywhere:
+#
+#     # In any template:
+#     <p>Version: {{ version }}</p>
+#     {% if has_dct %}DCT mode available{% endif %}
+#
+# This is great for:
+# - Version numbers (show in footer)
+# - Feature flags (has_dct, auth_enabled)
+# - User info (username, is_admin)
+# - Global config (max sizes, limits)
+#
+# The function runs on EVERY request, so keep it fast.
+# Don't do expensive database queries here.
 
 
 @app.context_processor
@@ -963,6 +1117,13 @@ def encode_page():
         # Check if async mode requested
         is_async = request.form.get("async") == "true" or request.headers.get("X-Async") == "true"
 
+        def _error_response(msg):
+            """Return error as JSON (async) or HTML flash (sync)."""
+            if is_async:
+                return jsonify({"error": msg}), 400
+            flash(msg, "error")
+            return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+
         try:
             # Get files
             ref_photo = request.files.get("reference_photo")
@@ -971,12 +1132,10 @@ def encode_page():
             payload_file = request.files.get("payload_file")
 
             if not ref_photo or not carrier:
-                flash("Both reference photo and carrier image are required", "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response("Both reference photo and carrier image are required")
 
             if not allowed_image(ref_photo.filename) or not allowed_image(carrier.filename):
-                flash("Invalid file type. Use PNG, JPG, or BMP", "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response("Invalid file type. Use PNG, JPG, or BMP")
 
             # Get form data - v3.2.0: renamed from day_phrase to passphrase
             message = request.form.get("message", "")
@@ -1005,8 +1164,7 @@ def encode_page():
 
             # Check DCT availability
             if embed_mode == "dct" and not has_dct_support():
-                flash("DCT mode requires scipy. Install with: pip install scipy", "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response("DCT mode requires scipy. Install with: pip install scipy")
 
             # Determine payload
             if payload_type == "file" and payload_file and payload_file.filename:
@@ -1015,8 +1173,7 @@ def encode_page():
 
                 result = validate_file_payload(file_data, payload_file.filename)
                 if not result.is_valid:
-                    flash(result.error_message, "error")
-                    return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                    return _error_response(result.error_message)
 
                 mime_type, _ = mimetypes.guess_type(payload_file.filename)
                 payload = FilePayload(
@@ -1026,20 +1183,17 @@ def encode_page():
                 # Text message
                 result = validate_message(message)
                 if not result.is_valid:
-                    flash(result.error_message, "error")
-                    return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                    return _error_response(result.error_message)
                 payload = message
 
             # v3.2.0: Renamed from day_phrase
             if not passphrase:
-                flash("Passphrase is required", "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response("Passphrase is required")
 
             # v3.2.0: Validate passphrase
             result = validate_passphrase(passphrase)
             if not result.is_valid:
-                flash(result.error_message, "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response(result.error_message)
 
             # Show warning if passphrase is short
             if result.warning:
@@ -1049,12 +1203,19 @@ def encode_page():
             ref_data = ref_photo.read()
             carrier_data = carrier.read()
 
-            # Handle RSA key - can come from .pem file or QR code image
+            # Handle RSA key - can come from .pem file, QR code image, or webcam-scanned PEM (v4.1.5)
             rsa_key_data = None
+            rsa_key_pem = request.form.get("rsa_key_pem", "").strip()
             rsa_key_qr = request.files.get("rsa_key_qr")
             rsa_key_from_qr = False
 
-            if rsa_key_file and rsa_key_file.filename:
+            if rsa_key_pem:
+                # Webcam-scanned PEM key (v4.1.5+) - may be compressed (zlib or zstd)
+                if is_compressed(rsa_key_pem):
+                    rsa_key_pem = decompress_data(rsa_key_pem)
+                rsa_key_data = rsa_key_pem.encode("utf-8")
+                rsa_key_from_qr = True
+            elif rsa_key_file and rsa_key_file.filename:
                 rsa_key_data = rsa_key_file.read()
             elif rsa_key_qr and rsa_key_qr.filename and HAS_QRCODE_READ:
                 qr_image_data = rsa_key_qr.read()
@@ -1063,21 +1224,18 @@ def encode_page():
                     rsa_key_data = key_pem.encode("utf-8")
                     rsa_key_from_qr = True
                 else:
-                    flash("Could not extract RSA key from QR code image.", "error")
-                    return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                    return _error_response("Could not extract RSA key from QR code image.")
 
             # Validate security factors
             result = validate_security_factors(pin, rsa_key_data)
             if not result.is_valid:
-                flash(result.error_message, "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response(result.error_message)
 
             # Validate PIN if provided
             if pin:
                 result = validate_pin(pin)
                 if not result.is_valid:
-                    flash(result.error_message, "error")
-                    return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                    return _error_response(result.error_message)
 
             # Determine key password
             key_password = None if rsa_key_from_qr else (rsa_password if rsa_password else None)
@@ -1086,14 +1244,12 @@ def encode_page():
             if rsa_key_data:
                 result = validate_rsa_key(rsa_key_data, key_password)
                 if not result.is_valid:
-                    flash(result.error_message, "error")
-                    return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                    return _error_response(result.error_message)
 
             # Validate carrier image
             result = validate_image(carrier_data, "Carrier image")
             if not result.is_valid:
-                flash(result.error_message, "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response(result.error_message)
 
             # Pre-check payload capacity BEFORE encode (fail fast)
             from stegasoo.steganography import will_fit_by_mode
@@ -1113,8 +1269,7 @@ def encode_page():
                     alt_check = will_fit_by_mode(payload_size, carrier_data, embed_mode="lsb")
                     if alt_check.get("fits"):
                         error_msg += " - Try LSB mode instead."
-                flash(error_msg, "error")
-                return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+                return _error_response(error_msg)
 
             # Build encode params for either sync or async
             encode_params = {
@@ -1215,14 +1370,11 @@ def encode_page():
             return redirect(url_for("encode_result", file_id=file_id))
 
         except CapacityError as e:
-            flash(str(e), "error")
-            return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+            return _error_response(str(e))
         except StegasooError as e:
-            flash(str(e), "error")
-            return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+            return _error_response(str(e))
         except Exception as e:
-            flash(f"Error: {e}", "error")
-            return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
+            return _error_response(f"Error: {e}")
 
     return render_template("encode.html", has_qrcode_read=HAS_QRCODE_READ)
 
@@ -1371,6 +1523,82 @@ def encode_cleanup(file_id):
 # ============================================================================
 
 
+def _run_decode_job(job_id: str, decode_params: dict) -> None:
+    """Background thread function for async decode."""
+    progress_file = get_progress_file_path(job_id)
+
+    try:
+        _store_job(job_id, {"status": "running", "created": time.time()})
+
+        # Run decode with progress file
+        decode_result = subprocess_stego.decode(
+            stego_data=decode_params["stego_data"],
+            reference_data=decode_params["ref_data"],
+            passphrase=decode_params["passphrase"],
+            pin=decode_params.get("pin"),
+            rsa_key_data=decode_params.get("rsa_key_data"),
+            rsa_password=decode_params.get("rsa_password"),
+            embed_mode=decode_params.get("embed_mode", "auto"),
+            channel_key=decode_params.get("channel_key"),
+            progress_file=progress_file,
+        )
+
+        if not decode_result.success:
+            _store_job(
+                job_id,
+                {
+                    "status": "error",
+                    "error": decode_result.error or "Decoding failed",
+                    "error_type": decode_result.error_type,
+                    "created": time.time(),
+                },
+            )
+            return
+
+        # Store result based on type
+        if decode_result.is_file:
+            file_id = secrets.token_urlsafe(16)
+            filename = decode_result.filename or "decoded_file"
+            temp_storage.save_temp_file(file_id, decode_result.file_data, {
+                "filename": filename,
+                "mime_type": decode_result.mime_type,
+            })
+            _store_job(
+                job_id,
+                {
+                    "status": "complete",
+                    "file_id": file_id,
+                    "is_file": True,
+                    "filename": filename,
+                    "file_size": len(decode_result.file_data),
+                    "mime_type": decode_result.mime_type,
+                    "created": time.time(),
+                },
+            )
+        else:
+            _store_job(
+                job_id,
+                {
+                    "status": "complete",
+                    "is_file": False,
+                    "message": decode_result.message,
+                    "created": time.time(),
+                },
+            )
+
+    except Exception as e:
+        _store_job(
+            job_id,
+            {
+                "status": "error",
+                "error": str(e),
+                "created": time.time(),
+            },
+        )
+    finally:
+        cleanup_progress_file(job_id)
+
+
 @app.route("/decode", methods=["GET", "POST"])
 @login_required
 def decode_page():
@@ -1414,12 +1642,19 @@ def decode_page():
             ref_data = ref_photo.read()
             stego_data = stego_image.read()
 
-            # Handle RSA key - can come from .pem file or QR code image
+            # Handle RSA key - can come from .pem file, QR code image, or webcam-scanned PEM (v4.1.5)
             rsa_key_data = None
+            rsa_key_pem = request.form.get("rsa_key_pem", "").strip()
             rsa_key_qr = request.files.get("rsa_key_qr")
             rsa_key_from_qr = False
 
-            if rsa_key_file and rsa_key_file.filename:
+            if rsa_key_pem:
+                # Webcam-scanned PEM key (v4.1.5+) - may be compressed (zlib or zstd)
+                if is_compressed(rsa_key_pem):
+                    rsa_key_pem = decompress_data(rsa_key_pem)
+                rsa_key_data = rsa_key_pem.encode("utf-8")
+                rsa_key_from_qr = True
+            elif rsa_key_file and rsa_key_file.filename:
                 rsa_key_data = rsa_key_file.read()
             elif rsa_key_qr and rsa_key_qr.filename and HAS_QRCODE_READ:
                 qr_image_data = rsa_key_qr.read()
@@ -1454,6 +1689,29 @@ def decode_page():
                     flash(result.error_message, "error")
                     return render_template("decode.html", has_qrcode_read=HAS_QRCODE_READ)
 
+            # Check for async mode (v4.1.5)
+            is_async = request.form.get("async") == "true" or request.headers.get("X-Async") == "true"
+
+            # Build decode params
+            decode_params = {
+                "stego_data": stego_data,
+                "ref_data": ref_data,
+                "passphrase": passphrase,
+                "pin": pin if pin else None,
+                "rsa_key_data": rsa_key_data,
+                "rsa_password": key_password,
+                "embed_mode": embed_mode,
+                "channel_key": channel_key,
+            }
+
+            # ASYNC MODE: Start background job and return JSON
+            if is_async:
+                job_id = generate_job_id()
+                _store_job(job_id, {"status": "pending", "created": time.time()})
+                _executor.submit(_run_decode_job, job_id, decode_params)
+                return jsonify({"job_id": job_id, "status": "pending"})
+
+            # SYNC MODE: Run inline (original behavior)
             # v4.0.0: Include channel_key parameter
             # Use subprocess-isolated decode to prevent crashes
             decode_result = subprocess_stego.decode(
@@ -1559,6 +1817,92 @@ def decode_download(file_id):
     )
 
 
+# ============================================================================
+# DECODE PROGRESS ENDPOINTS (v4.1.5)
+# ============================================================================
+
+
+@app.route("/decode/status/<job_id>")
+@login_required
+def decode_status(job_id):
+    """Get the status of an async decode job."""
+    job = _get_job(job_id)
+    if not job:
+        return jsonify({"error": "Job not found"}), 404
+
+    response = {"status": job.get("status", "unknown")}
+
+    if job["status"] == "complete":
+        response["is_file"] = job.get("is_file", False)
+        if job.get("is_file"):
+            response["file_id"] = job.get("file_id")
+            response["filename"] = job.get("filename")
+            response["file_size"] = job.get("file_size")
+            response["mime_type"] = job.get("mime_type")
+        else:
+            response["message"] = job.get("message")
+    elif job["status"] == "error":
+        response["error"] = job.get("error", "Unknown error")
+        response["error_type"] = job.get("error_type")
+
+    return jsonify(response)
+
+
+@app.route("/decode/progress/<job_id>")
+@login_required
+def decode_progress(job_id):
+    """Get the progress of an async decode job."""
+    progress = read_progress(job_id)
+    if progress:
+        return jsonify(progress)
+
+    # No progress file yet - check job status
+    job = _get_job(job_id)
+    if not job:
+        return jsonify({"error": "Job not found"}), 404
+
+    if job["status"] == "complete":
+        return jsonify({"percent": 100, "phase": "complete"})
+    elif job["status"] == "error":
+        return jsonify({"percent": 0, "phase": "error", "error": job.get("error")})
+    elif job["status"] == "pending":
+        return jsonify({"percent": 0, "phase": "starting"})
+
+    # Running but no progress file yet
+    return jsonify({"percent": 5, "phase": "reading"})
+
+
+@app.route("/decode/result/<job_id>")
+@login_required
+def decode_result(job_id):
+    """Get the result page for an async decode job."""
+    job = _get_job(job_id)
+    if not job:
+        flash("Job not found or expired.", "error")
+        return redirect(url_for("decode_page"))
+
+    if job["status"] != "complete":
+        flash("Decode not complete.", "error")
+        return redirect(url_for("decode_page"))
+
+    if job.get("is_file"):
+        return render_template(
+            "decode.html",
+            decoded_file=True,
+            file_id=job.get("file_id"),
+            filename=job.get("filename"),
+            file_size=format_size(job.get("file_size", 0)),
+            mime_type=job.get("mime_type"),
+            has_qrcode_read=HAS_QRCODE_READ,
+        )
+    else:
+        return render_template(
+            "decode.html",
+            decoded_message=job.get("message"),
+            has_qrcode_read=HAS_QRCODE_READ,
+        )
+
+
 @app.route("/about")
 def about():
     from stegasoo.channel import get_channel_status
@@ -1753,6 +2097,145 @@ def api_tools_exif_clear():
         return jsonify({"success": False, "error": str(e)}), 500
 
 
+@app.route("/api/tools/rotate", methods=["POST"])
+@login_required
+def api_tools_rotate():
+    """Rotate and/or flip an image."""
+    from PIL import Image
+
+    image_file = request.files.get("image")
+    if not image_file:
+        return jsonify({"success": False, "error": "No image provided"}), 400
+
+    rotation = int(request.form.get("rotation", 0))
+    flip_h = request.form.get("flip_h", "false").lower() == "true"
+    flip_v = request.form.get("flip_v", "false").lower() == "true"
+
+    try:
+        img = Image.open(io.BytesIO(image_file.read()))
+
+        # Apply rotation (PIL rotates counter-clockwise, so negate)
+        if rotation:
+            img = img.rotate(-rotation, expand=True)
+
+        # Apply flips
+        if flip_h:
+            img = img.transpose(Image.FLIP_LEFT_RIGHT)
+        if flip_v:
+            img = img.transpose(Image.FLIP_TOP_BOTTOM)
+
+        # Output as PNG (lossless)
+        buffer = io.BytesIO()
+        img.save(buffer, format="PNG")
+        buffer.seek(0)
+
+        stem = (
+            image_file.filename.rsplit(".", 1)[0]
+            if "." in image_file.filename
+            else image_file.filename
+        )
+        return send_file(
+            buffer,
+            mimetype="image/png",
+            as_attachment=True,
+            download_name=f"{stem}_transformed.png",
+        )
+    except Exception as e:
+        return jsonify({"success": False, "error": str(e)}), 500
+
+
+@app.route("/api/tools/compress", methods=["POST"])
+@login_required
+def api_tools_compress():
+    """Compress image to JPEG at specified quality."""
+    from PIL import Image
+
+    image_file = request.files.get("image")
+    if not image_file:
+        return jsonify({"success": False, "error": "No image provided"}), 400
+
+    quality = int(request.form.get("quality", 85))
+    quality = max(10, min(100, quality))  # Clamp to valid range
+
+    try:
+        img = Image.open(io.BytesIO(image_file.read()))
+
+        # Convert to RGB if necessary (JPEG doesn't support alpha)
+        if img.mode in ("RGBA", "LA", "P"):
+            img = img.convert("RGB")
+
+        buffer = io.BytesIO()
+        img.save(buffer, format="JPEG", quality=quality)
+        buffer.seek(0)
+
+        stem = (
+            image_file.filename.rsplit(".", 1)[0]
+            if "." in image_file.filename
+            else image_file.filename
+        )
+        return send_file(
+            buffer,
+            mimetype="image/jpeg",
+            as_attachment=True,
+            download_name=f"{stem}_q{quality}.jpg",
+        )
+    except Exception as e:
+        return jsonify({"success": False, "error": str(e)}), 500
+
+
+@app.route("/api/tools/convert", methods=["POST"])
+@login_required
+def api_tools_convert():
+    """Convert image to different format."""
+    from PIL import Image
+
+    image_file = request.files.get("image")
+    if not image_file:
+        return jsonify({"success": False, "error": "No image provided"}), 400
+
+    output_format = request.form.get("format", "PNG").upper()
+    quality = int(request.form.get("quality", 90))
+    quality = max(10, min(100, quality))
+
+    # Validate format
+    format_map = {
+        "PNG": ("png", "image/png"),
+        "JPEG": ("jpg", "image/jpeg"),
+        "WEBP": ("webp", "image/webp"),
+    }
+    if output_format not in format_map:
+        return jsonify({"success": False, "error": f"Unsupported format: {output_format}"}), 400
+
+    try:
+        img = Image.open(io.BytesIO(image_file.read()))
+
+        # Convert to RGB for JPEG (no alpha)
+        if output_format == "JPEG" and img.mode in ("RGBA", "LA", "P"):
+            img = img.convert("RGB")
+
+        buffer = io.BytesIO()
+        save_kwargs = {"format": output_format}
+        if output_format in ("JPEG", "WEBP"):
+            save_kwargs["quality"] = quality
+        img.save(buffer, **save_kwargs)
+        buffer.seek(0)
+
+        ext, mimetype = format_map[output_format]
+        stem = (
+            image_file.filename.rsplit(".", 1)[0]
+            if "." in image_file.filename
+            else image_file.filename
+        )
+        return send_file(
+            buffer,
+            mimetype=mimetype,
+            as_attachment=True,
+            download_name=f"{stem}.{ext}",
+        )
+    except Exception as e:
+        return jsonify({"success": False, "error": str(e)}), 500
+
+
 # Add these two test routes anywhere in app.py after the app = Flask(...) line:
 
 
@@ -2202,6 +2685,70 @@ def api_channel_key_use(key_id):
 # ============================================================================
 
 
+@app.route("/admin/settings")
+@admin_required
+def admin_settings():
+    """System settings page (admin only)."""
+    import platform
+    import sys
+
+    from stegasoo import __version__
+    from stegasoo.channel import get_channel_status
+
+    channel_status = get_channel_status()
+
+    return render_template(
+        "admin/settings.html",
+        # Channel info (key hidden until password verified)
+        channel_configured=channel_status["configured"],
+        channel_fingerprint=channel_status.get("fingerprint"),
+        channel_source=channel_status.get("source"),
+        # Server config
+        hostname=os.environ.get("STEGASOO_HOSTNAME") or socket.gethostname(),
+        port=os.environ.get("STEGASOO_PORT", "5000"),
+        https_enabled=app.config.get("HTTPS_ENABLED", False),
+        auth_enabled=app.config.get("AUTH_ENABLED", True),
+        max_payload_kb=MAX_FILE_PAYLOAD_SIZE // 1024,
+        max_upload_mb=MAX_FILE_SIZE // (1024 * 1024),
+        dct_available=has_dct_support(),
+        qr_available=HAS_QRCODE_READ,
+        # Environment
+        version=__version__,
+        python_version=f"{sys.version_info.major}.{sys.version_info.minor}.{sys.version_info.micro}",
+        platform=platform.system(),
+        kdf_type="Argon2id" if has_argon2() else "PBKDF2",
+    )
+
+
+@app.route("/admin/settings/unlock", methods=["POST"])
+@admin_required
+def admin_settings_unlock():
+    """Verify password and return channel key (AJAX)."""
+    from stegasoo.channel import get_channel_status
+
+    data = request.get_json() or {}
+    password = data.get("password", "")
+
+    if not password:
+        return jsonify({"success": False, "error": "Password required"})
+
+    # Get current user and verify password
+    username = get_username()
+    user = verify_user_password(username, password)
+
+    if not user:
+        return jsonify({"success": False, "error": "Incorrect password"})
+
+    # Password verified - return channel key
+    channel_status = get_channel_status()
+    channel_key = channel_status.get("key") if channel_status["configured"] else ""
+
+    return jsonify({
+        "success": True,
+        "channel_key": channel_key
+    })
+
+
 @app.route("/admin/users")
 @admin_required
 def admin_users():
@@ -2332,7 +2879,8 @@ if __name__ == "__main__":
     # HTTPS configuration
     ssl_context = None
     if app.config.get("HTTPS_ENABLED", False):
-        hostname = os.environ.get("STEGASOO_HOSTNAME", "localhost")
+        import socket
+        hostname = os.environ.get("STEGASOO_HOSTNAME") or socket.gethostname()
         try:
             cert_path, key_path = ensure_certs(base_dir, hostname)
             if cert_path.exists() and key_path.exists():

frontends/web/dev_run.sh

@@ -0,0 +1,52 @@
+#!/bin/bash
+# Stegasoo Web Frontend - Development Runner
+# Press 'r' to restart, 'q' to quit (single keypress, no Enter needed)
+
+cd "$(dirname "$0")"
+
+PID=""
+
+cleanup() {
+    echo -e "\n\033[33mShutting down...\033[0m"
+    [[ -n "$PID" ]] && kill "$PID" 2>/dev/null
+    stty sane 2>/dev/null
+    exit 0
+}
+
+trap cleanup SIGINT SIGTERM EXIT
+
+start_server() {
+    clear
+    echo -e "\033[36m┌──────────────────────────────────────┐\033[0m"
+    echo -e "\033[36m│  Stegasoo Dev Server                 │\033[0m"
+    echo -e "\033[36m│  \033[0m[r] restart  [q] quit\033[36m              │\033[0m"
+    echo -e "\033[36m└──────────────────────────────────────┘\033[0m"
+
+    pkill -f "python app.py" 2>/dev/null
+    sleep 0.3
+
+    python app.py 2>&1 &
+    PID=$!
+    echo -e "\033[32m✓ Running on http://localhost:5000 (PID: $PID)\033[0m\n"
+}
+
+start_server
+
+# Single keypress mode
+stty -echo -icanon time 0 min 0
+
+while true; do
+    key=$(dd bs=1 count=1 2>/dev/null)
+    case "$key" in
+        r|R) start_server ;;
+        q|Q) cleanup ;;
+    esac
+
+    # Check if crashed
+    if [[ -n "$PID" ]] && ! kill -0 "$PID" 2>/dev/null; then
+        echo -e "\033[31m✗ Crashed! Press 'r' to restart\033[0m"
+        PID=""
+    fi
+
+    sleep 0.1
+done

frontends/web/docker-entrypoint.sh

@@ -0,0 +1,75 @@
+#!/bin/bash
+#
+# Docker entrypoint for Stegasoo Web UI
+# Handles SSL certificate generation and gunicorn startup
+#
+# Supports mkcert for browser-trusted certificates (no warning screen)
+#
+
+set -e
+
+CERT_DIR="/app/frontends/web/certs"
+CERT_FILE="$CERT_DIR/cert.pem"
+KEY_FILE="$CERT_DIR/key.pem"
+HOSTNAME="${STEGASOO_HOSTNAME:-localhost}"
+
+# Generate SSL certificates
+# Priority: 1) Existing certs, 2) mkcert (trusted), 3) openssl (self-signed)
+generate_certs() {
+    if [ -f "$CERT_FILE" ] && [ -f "$KEY_FILE" ]; then
+        echo "Using existing SSL certificates."
+        return
+    fi
+
+    mkdir -p "$CERT_DIR"
+
+    # Try mkcert first (creates browser-trusted certs)
+    if command -v mkcert &> /dev/null; then
+        echo "Generating trusted certificate with mkcert for $HOSTNAME..."
+        cd "$CERT_DIR"
+        mkcert -key-file key.pem -cert-file cert.pem "$HOSTNAME" localhost 127.0.0.1 ::1
+        echo "Trusted certificate generated."
+        echo ""
+        echo "  To trust on other devices, install the CA cert from:"
+        echo "  $(mkcert -CAROOT)/rootCA.pem"
+        echo ""
+        return
+    fi
+
+    # Fallback to self-signed (shows browser warning)
+    echo "Generating self-signed SSL certificate for $HOSTNAME..."
+    echo "(Install mkcert for browser-trusted certs without warnings)"
+
+    openssl req -x509 -newkey rsa:2048 \
+        -keyout "$KEY_FILE" \
+        -out "$CERT_FILE" \
+        -sha256 -days 365 -nodes \
+        -subj "/CN=$HOSTNAME" \
+        -addext "subjectAltName=DNS:$HOSTNAME,DNS:localhost,IP:127.0.0.1" \
+        2>/dev/null
+
+    echo "Self-signed certificate generated."
+}
+
+# Start gunicorn with appropriate settings
+if [ "${STEGASOO_HTTPS_ENABLED:-false}" = "true" ]; then
+    echo "HTTPS mode enabled"
+    generate_certs
+
+    exec gunicorn \
+        --bind 0.0.0.0:5000 \
+        --workers 2 \
+        --threads 4 \
+        --timeout 120 \
+        --certfile "$CERT_FILE" \
+        --keyfile "$KEY_FILE" \
+        app:app
+else
+    echo "HTTP mode (HTTPS disabled)"
+    exec gunicorn \
+        --bind 0.0.0.0:5000 \
+        --workers 2 \
+        --threads 4 \
+        --timeout 120 \
+        app:app
+fi

frontends/web/ssl_utils.py

@@ -7,6 +7,7 @@ Uses cryptography library (already a dependency).
 
 import datetime
 import ipaddress
+import socket
 from pathlib import Path
 
 from cryptography import x509
@@ -15,6 +16,33 @@ from cryptography.hazmat.primitives.asymmetric import rsa
 from cryptography.x509.oid import NameOID
 
 
+def _get_local_ips() -> list[str]:
+    """Get local IP addresses for this machine."""
+    ips = []
+    try:
+        # Get hostname and resolve to IP
+        hostname = socket.gethostname()
+        for addr_info in socket.getaddrinfo(hostname, None, socket.AF_INET):
+            ip = addr_info[4][0]
+            if ip not in ips and not ip.startswith("127."):
+                ips.append(ip)
+    except Exception:
+        pass
+
+    # Also try connecting to external to get primary interface IP
+    try:
+        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        s.connect(("8.8.8.8", 80))
+        ip = s.getsockname()[0]
+        if ip not in ips:
+            ips.append(ip)
+        s.close()
+    except Exception:
+        pass
+
+    return ips
+
+
 def get_cert_paths(base_dir: Path) -> tuple[Path, Path]:
     """Get paths for cert and key files."""
     cert_dir = base_dir / "certs"
@@ -64,12 +92,26 @@ def generate_self_signed_cert(
         x509.DNSName("localhost"),
         x509.IPAddress(ipaddress.IPv4Address("127.0.0.1")),
     ]
+
+    # Add hostname.local for mDNS access
+    if not hostname.endswith(".local"):
+        san_list.append(x509.DNSName(f"{hostname}.local"))
+
     # Add the hostname as IP if it looks like one
     try:
         san_list.append(x509.IPAddress(ipaddress.IPv4Address(hostname)))
     except ipaddress.AddressValueError:
         pass
 
+    # Add local network IPs
+    for local_ip in _get_local_ips():
+        try:
+            ip_addr = ipaddress.IPv4Address(local_ip)
+            if x509.IPAddress(ip_addr) not in san_list:
+                san_list.append(x509.IPAddress(ip_addr))
+        except (ipaddress.AddressValueError, ValueError):
+            pass
+
     now = datetime.datetime.now(datetime.timezone.utc)
     cert = (
         x509.CertificateBuilder()

frontends/web/static/js/generate.js

@@ -231,20 +231,14 @@ const StegasooGenerate = {
         printWindow.document.write(`<!DOCTYPE html>
 <html>
 <head>
-    <title>Stegasoo RSA Key QR Code</title>
+    <title>QR Code</title>
     <style>
-        body { display: flex; flex-direction: column; align-items: center; justify-content: center; min-height: 100vh; margin: 0; font-family: sans-serif; }
+        body { display: flex; flex-direction: column; align-items: center; justify-content: center; min-height: 100vh; margin: 0; }
         img { max-width: 400px; }
-        .warning { margin-top: 20px; padding: 10px; border: 2px solid #ff9800; background: #fff3e0; max-width: 400px; text-align: center; font-size: 12px; }
     </style>
 </head>
 <body>
-    <h2>Stegasoo RSA Private Key</h2>
-    <img src="${qrImg.src}" alt="RSA Key QR Code">
-    <div class="warning">
-        <strong>Warning:</strong> This QR code contains your unencrypted RSA private key.
-        Store securely and destroy after use.
-    </div>
+    <img src="${qrImg.src}" alt="QR Code">
     <script>window.onload = function() { window.print(); }<\/script>
 </body>
 </html>`);

frontends/web/static/js/stegasoo.js

@@ -333,56 +333,68 @@ const Stegasoo = {
     generateEmbedTraces(container, width, height) {
         // Color classes for variety
         const colors = ['color-yellow', 'color-cyan', 'color-purple', 'color-blue'];
-        
-        // Generate 6-8 snake paths spread across the whole image
-        const numPaths = 6 + Math.floor(Math.random() * 3);
-        
-        for (let p = 0; p < numPaths; p++) {
-            // Each path gets a random color
-            const pathColor = colors[Math.floor(Math.random() * colors.length)];
-            
-            // Distribute starting points across the image
-            let x = (width * 0.1) + (Math.random() * width * 0.8);
-            let y = (height * 0.1) + (Math.random() * height * 0.8);
-            let delay = p * 40;
-            
-            // Each path has 3-5 segments for more coverage
-            const numSegments = 3 + Math.floor(Math.random() * 3);
-            let horizontal = Math.random() > 0.5;
-            
-            for (let s = 0; s < numSegments; s++) {
-                const trace = document.createElement('div');
-                trace.className = 'embed-trace ' + (horizontal ? 'h' : 'v') + ' ' + pathColor;
-                
-                const length = 30 + Math.random() * 60;
-                trace.style.left = x + 'px';
-                trace.style.top = y + 'px';
-                trace.style.animationDelay = delay + 'ms';
-                
-                if (horizontal) {
-                    trace.style.width = length + 'px';
-                } else {
-                    trace.style.height = length + 'px';
+
+        // Grid-based distribution: divide image into cells for even coverage
+        const gridCols = 5;
+        const gridRows = 4;
+        const cellWidth = width / gridCols;
+        const cellHeight = height / gridRows;
+
+        let pathIndex = 0;
+
+        // Spawn 1-2 paths from each grid cell for even distribution
+        for (let row = 0; row < gridRows; row++) {
+            for (let col = 0; col < gridCols; col++) {
+                // 1-2 paths per cell
+                const pathsInCell = 1 + Math.floor(Math.random() * 2);
+
+                for (let p = 0; p < pathsInCell; p++) {
+                    const pathColor = colors[Math.floor(Math.random() * colors.length)];
+
+                    // Start within this grid cell (with padding)
+                    let x = (col * cellWidth) + (cellWidth * 0.15) + (Math.random() * cellWidth * 0.7);
+                    let y = (row * cellHeight) + (cellHeight * 0.15) + (Math.random() * cellHeight * 0.7);
+                    let delay = pathIndex * 15;
+
+                    // Each path has 3-5 short segments
+                    const numSegments = 3 + Math.floor(Math.random() * 3);
+                    let horizontal = Math.random() > 0.5;
+
+                    for (let s = 0; s < numSegments; s++) {
+                        const trace = document.createElement('div');
+                        trace.className = 'embed-trace ' + (horizontal ? 'h' : 'v') + ' ' + pathColor;
+
+                        // Shorter segments: 12-30px for denser circuit look
+                        const length = 12 + Math.random() * 18;
+                        trace.style.left = Math.max(0, Math.min(x, width - length)) + 'px';
+                        trace.style.top = Math.max(0, Math.min(y, height - length)) + 'px';
+                        trace.style.animationDelay = delay + 'ms';
+
+                        if (horizontal) {
+                            trace.style.width = length + 'px';
+                        } else {
+                            trace.style.height = length + 'px';
+                        }
+
+                        container.appendChild(trace);
+
+                        // Move position for next segment
+                        if (horizontal) {
+                            x += length * (Math.random() > 0.5 ? 1 : -1);
+                        } else {
+                            y += length * (Math.random() > 0.5 ? 1 : -1);
+                        }
+
+                        // Keep within bounds
+                        x = Math.max(5, Math.min(x, width - 20));
+                        y = Math.max(5, Math.min(y, height - 20));
+
+                        // Alternate direction (90 degree turn)
+                        horizontal = !horizontal;
+                        delay += 20;
+                    }
+                    pathIndex++;
                 }
-                
-                container.appendChild(trace);
-                
-                // Move position for next segment
-                if (horizontal) {
-                    x += length;
-                } else {
-                    y += length;
-                }
-                
-                // Wrap around if out of bounds to keep traces in view
-                if (x > width - 20) x = 10 + Math.random() * 40;
-                if (y > height - 20) y = 10 + Math.random() * 40;
-                if (x < 10) x = width - 60 + Math.random() * 40;
-                if (y < 10) y = height - 60 + Math.random() * 40;
-                
-                // Alternate direction (90 degree turn)
-                horizontal = !horizontal;
-                delay += 30;
             }
         }
     },
@@ -997,7 +1009,9 @@ const Stegasoo = {
                 const percent = progressData.percent || 0;
                 const phase = progressData.phase || 'processing';
 
-                this.updateProgress(percent, this.formatPhase(phase));
+                // Use indeterminate mode for initializing/starting phases
+                const isIndeterminate = (phase === 'initializing' || phase === 'starting');
+                this.updateProgress(percent, this.formatPhase(phase), isIndeterminate);
 
                 // Continue polling
                 setTimeout(poll, 500);
@@ -1017,7 +1031,7 @@ const Stegasoo = {
     formatPhase(phase) {
         const phases = {
             'starting': 'Starting...',
-            'initializing': 'Initializing...',
+            'initializing': 'Deriving keys (may take a moment)...',
             'embedding': 'Embedding data...',
             'saving': 'Saving image...',
             'finalizing': 'Finalizing...',
@@ -1058,8 +1072,9 @@ const Stegasoo = {
             document.body.appendChild(modal);
         }
 
-        // Reset progress
-        this.updateProgress(0, 'Initializing...');
+        // Reset progress tracking and start with indeterminate state
+        this.resetProgressTracking();
+        this.updateProgress(0, 'Initializing...', true);
 
         // Show modal
         const bsModal = new bootstrap.Modal(modal);
@@ -1078,16 +1093,446 @@ const Stegasoo = {
     },
 
     /**
-     * Update progress bar and text
+     * Track max progress to prevent backwards jumps
      */
-    updateProgress(percent, phase) {
+    _maxProgress: 0,
+
+    /**
+     * Reset progress tracking (call when starting new operation)
+     */
+    resetProgressTracking() {
+        this._maxProgress = 0;
+    },
+
+    /**
+     * Update progress bar and text
+     * Supports indeterminate mode for initializing phase (barber pole at full width)
+     */
+    updateProgress(percent, phase, indeterminate = false) {
         const progressBar = document.getElementById('progressBar');
         const progressText = document.getElementById('progressText');
         const phaseText = document.getElementById('progressPhase');
 
-        if (progressBar) progressBar.style.width = percent + '%';
-        if (progressText) progressText.textContent = Math.round(percent) + '%';
-        if (phaseText) phaseText.textContent = phase;
+        if (indeterminate) {
+            // Barber pole animation at full width, no percentage
+            if (progressBar) {
+                progressBar.style.width = '100%';
+                progressBar.classList.add('progress-bar-striped', 'progress-bar-animated');
+            }
+            if (progressText) progressText.textContent = '';
+            if (phaseText) phaseText.textContent = phase;
+        } else {
+            // Determinate progress - never go backwards
+            const safePercent = Math.max(percent, this._maxProgress);
+            this._maxProgress = safePercent;
+
+            if (progressBar) {
+                progressBar.style.width = safePercent + '%';
+                // Keep animation but show actual progress
+                progressBar.classList.add('progress-bar-striped', 'progress-bar-animated');
+            }
+            if (progressText) progressText.textContent = Math.round(safePercent) + '%';
+            if (phaseText) phaseText.textContent = phase;
+        }
+    },
+
+    // ========================================================================
+    // ASYNC DECODE WITH PROGRESS (v4.1.5)
+    // ========================================================================
+
+    /**
+     * Submit decode form asynchronously with progress tracking
+     * @param {HTMLFormElement} form - The decode form
+     * @param {HTMLElement} btn - The submit button
+     */
+    async submitDecodeAsync(form, btn) {
+        const formData = new FormData(form);
+        formData.append('async', 'true');
+
+        // Show progress modal
+        this.showProgressModal('Decoding');
+
+        try {
+            // Start decode job
+            const response = await fetch('/decode', {
+                method: 'POST',
+                body: formData,
+            });
+
+            if (!response.ok) {
+                throw new Error('Failed to start decode');
+            }
+
+            const result = await response.json();
+
+            if (result.error) {
+                throw new Error(result.error);
+            }
+
+            const jobId = result.job_id;
+
+            // Poll for progress
+            await this.pollDecodeProgress(jobId);
+
+        } catch (error) {
+            this.hideProgressModal();
+            alert('Decode failed: ' + error.message);
+            btn.disabled = false;
+            btn.innerHTML = '<i class="bi bi-unlock-fill me-2"></i>Decode';
+        }
+    },
+
+    /**
+     * Poll decode progress until complete
+     * @param {string} jobId - The job ID
+     */
+    async pollDecodeProgress(jobId) {
+        const poll = async () => {
+            try {
+                // Check status first
+                const statusResponse = await fetch(`/decode/status/${jobId}`);
+                const statusData = await statusResponse.json();
+
+                if (statusData.status === 'complete') {
+                    // Done - redirect to result page
+                    this.updateProgress(100, 'Complete!');
+                    setTimeout(() => {
+                        window.location.href = `/decode/result/${jobId}`;
+                    }, 500);
+                    return;
+                }
+
+                if (statusData.status === 'error') {
+                    // Handle specific error types
+                    const errorType = statusData.error_type;
+                    let errorMsg = statusData.error || 'Decode failed';
+
+                    if (errorType === 'DecryptionError' || errorMsg.toLowerCase().includes('decrypt')) {
+                        errorMsg = 'Wrong credentials. Double-check your reference photo, passphrase, PIN, and channel key.';
+                    }
+
+                    throw new Error(errorMsg);
+                }
+
+                // Get progress
+                const progressResponse = await fetch(`/decode/progress/${jobId}`);
+                const progressData = await progressResponse.json();
+
+                const percent = progressData.percent || 0;
+                const phase = progressData.phase || 'processing';
+
+                // Use indeterminate mode for initializing/starting/loading phases
+                const isIndeterminate = (phase === 'initializing' || phase === 'starting' || phase === 'loading');
+                this.updateProgress(percent, this.formatDecodePhase(phase), isIndeterminate);
+
+                // Continue polling
+                setTimeout(poll, 500);
+
+            } catch (error) {
+                this.hideProgressModal();
+                alert(error.message);
+            }
+        };
+
+        await poll();
+    },
+
+    /**
+     * Format decode phase name for display
+     */
+    formatDecodePhase(phase) {
+        const phases = {
+            'starting': 'Starting...',
+            'initializing': 'Deriving keys (may take a moment)...',
+            'loading': 'Deriving keys (may take a moment)...',
+            'reading': 'Reading image...',
+            'extracting': 'Extracting data...',
+            'decoding': 'Decoding data...',
+            'decrypting': 'Decrypting...',
+            'verifying': 'Verifying...',
+            'finalizing': 'Finalizing...',
+            'complete': 'Complete!',
+        };
+        return phases[phase] || phase;
+    },
+
+    // ========================================================================
+    // WEBCAM QR SCANNING (v4.1.5)
+    // ========================================================================
+
+    /**
+     * Active scanner instance
+     */
+    _qrScanner: null,
+    _qrScannerModal: null,
+    _qrScannerCallback: null,
+
+    /**
+     * Show webcam QR scanner modal
+     * @param {Function} onSuccess - Callback with decoded QR text
+     * @param {string} title - Modal title
+     */
+    showQrScanner(onSuccess, title = 'Scan QR Code') {
+        this._qrScannerCallback = onSuccess;
+
+        // Create modal if doesn't exist
+        let modal = document.getElementById('qrScannerModal');
+        if (!modal) {
+            modal = document.createElement('div');
+            modal.id = 'qrScannerModal';
+            modal.className = 'modal fade';
+            modal.innerHTML = `
+                <div class="modal-dialog modal-dialog-centered">
+                    <div class="modal-content bg-dark text-light">
+                        <div class="modal-header border-secondary">
+                            <h5 class="modal-title">
+                                <i class="bi bi-camera-video me-2"></i>
+                                <span id="qrScannerTitle">${title}</span>
+                            </h5>
+                            <button type="button" class="btn-close btn-close-white" data-bs-dismiss="modal"></button>
+                        </div>
+                        <div class="modal-body p-0">
+                            <div id="qrScannerReader" style="width: 100%;"></div>
+                            <div id="qrScannerStatus" class="text-center py-3 text-muted">
+                                <i class="bi bi-qr-code-scan me-2"></i>
+                                Point camera at QR code
+                            </div>
+                        </div>
+                        <div class="modal-footer border-secondary">
+                            <button type="button" class="btn btn-primary" id="qrCaptureBtn">
+                                <i class="bi bi-camera me-1"></i>Capture
+                            </button>
+                            <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Cancel</button>
+                        </div>
+                    </div>
+                </div>
+            `;
+            document.body.appendChild(modal);
+
+            // Clean up scanner when modal hides
+            modal.addEventListener('hidden.bs.modal', () => {
+                this.stopQrScanner();
+            });
+
+            // Manual capture button
+            modal.querySelector('#qrCaptureBtn')?.addEventListener('click', () => {
+                this.captureQrFrame();
+            });
+        }
+
+        // Update title
+        const titleEl = modal.querySelector('#qrScannerTitle');
+        if (titleEl) titleEl.textContent = title;
+
+        // Reset status
+        const statusEl = modal.querySelector('#qrScannerStatus');
+        if (statusEl) {
+            statusEl.innerHTML = '<i class="bi bi-qr-code-scan me-2"></i>Point camera at QR code';
+            statusEl.className = 'text-center py-3 text-muted';
+        }
+
+        // Show modal
+        this._qrScannerModal = new bootstrap.Modal(modal);
+        this._qrScannerModal.show();
+
+        // Start scanner after modal is shown
+        modal.addEventListener('shown.bs.modal', () => {
+            this.startQrScanner();
+        }, { once: true });
+    },
+
+    /**
+     * Start the QR scanner
+     */
+    startQrScanner() {
+        const readerEl = document.getElementById('qrScannerReader');
+        if (!readerEl) return;
+
+        // Check if Html5Qrcode is available
+        if (typeof Html5Qrcode === 'undefined') {
+            console.error('Html5Qrcode library not loaded');
+            const statusEl = document.getElementById('qrScannerStatus');
+            if (statusEl) {
+                statusEl.innerHTML = '<i class="bi bi-exclamation-triangle text-warning me-2"></i>QR scanner not available';
+            }
+            return;
+        }
+
+        this._qrScanner = new Html5Qrcode('qrScannerReader');
+
+        const config = {
+            fps: 10,
+            qrbox: { width: 250, height: 250 },
+            aspectRatio: 1.0,
+        };
+
+        this._qrScanner.start(
+            { facingMode: 'environment' }, // Prefer back camera
+            config,
+            (decodedText, decodedResult) => {
+                // QR code detected
+                this.onQrCodeDetected(decodedText);
+            },
+            (errorMessage) => {
+                // Scan error (ignore, keep scanning)
+            }
+        ).catch((err) => {
+            console.error('Failed to start scanner:', err);
+            const statusEl = document.getElementById('qrScannerStatus');
+            if (statusEl) {
+                if (err.toString().includes('Permission')) {
+                    statusEl.innerHTML = '<i class="bi bi-camera-video-off text-danger me-2"></i>Camera permission denied';
+                } else {
+                    statusEl.innerHTML = '<i class="bi bi-exclamation-triangle text-warning me-2"></i>Could not access camera';
+                }
+                statusEl.className = 'text-center py-3';
+            }
+        });
+    },
+
+    /**
+     * Capture a frame with countdown and try to decode
+     */
+    captureQrFrame() {
+        const statusEl = document.getElementById('qrScannerStatus');
+        const captureBtn = document.getElementById('qrCaptureBtn');
+        if (!statusEl || !this._qrScanner) return;
+
+        // Disable button during countdown
+        if (captureBtn) captureBtn.disabled = true;
+
+        let count = 3;
+        const countdown = () => {
+            if (count > 0) {
+                statusEl.innerHTML = `<i class="bi bi-camera me-2"></i><span style="font-size: 1.5rem; font-weight: bold;">${count}</span>`;
+                statusEl.className = 'text-center py-3 text-warning';
+                count--;
+                setTimeout(countdown, 1000);
+            } else {
+                // Capture!
+                statusEl.innerHTML = '<i class="bi bi-hourglass-split me-2"></i>Analyzing...';
+                statusEl.className = 'text-center py-3 text-info';
+
+                // Get video element and capture frame
+                const video = document.querySelector('#qrScannerReader video');
+                if (video) {
+                    const canvas = document.createElement('canvas');
+                    canvas.width = video.videoWidth;
+                    canvas.height = video.videoHeight;
+                    const ctx = canvas.getContext('2d');
+                    ctx.drawImage(video, 0, 0);
+
+                    // Stop the scanner before file scan (prevents conflicts)
+                    const scanner = this._qrScanner;
+                    scanner.stop().then(() => {
+                        canvas.toBlob((blob) => {
+                            const file = new File([blob], 'capture.png', { type: 'image/png' });
+                            scanner.scanFile(file, true)
+                                .then((decodedText) => {
+                                    this.onQrCodeDetected(decodedText);
+                                })
+                                .catch((err) => {
+                                    statusEl.innerHTML = '<i class="bi bi-x-circle text-danger me-2"></i>No QR code found. Try again.';
+                                    statusEl.className = 'text-center py-3 text-danger';
+                                    if (captureBtn) captureBtn.disabled = false;
+                                    // Restart the scanner
+                                    this.startQrScanner();
+                                });
+                        }, 'image/png');
+                    }).catch(() => {
+                        statusEl.innerHTML = '<i class="bi bi-x-circle text-danger me-2"></i>Scanner error';
+                        statusEl.className = 'text-center py-3 text-danger';
+                        if (captureBtn) captureBtn.disabled = false;
+                    });
+                } else {
+                    statusEl.innerHTML = '<i class="bi bi-x-circle text-danger me-2"></i>Camera not ready';
+                    statusEl.className = 'text-center py-3 text-danger';
+                    if (captureBtn) captureBtn.disabled = false;
+                }
+            }
+        };
+        countdown();
+    },
+
+    /**
+     * Stop the QR scanner
+     */
+    stopQrScanner() {
+        if (this._qrScanner) {
+            this._qrScanner.stop().then(() => {
+                this._qrScanner.clear();
+                this._qrScanner = null;
+            }).catch((err) => {
+                console.log('Scanner stop error:', err);
+            });
+        }
+    },
+
+    /**
+     * Handle detected QR code
+     * @param {string} text - Decoded QR text
+     */
+    onQrCodeDetected(text) {
+        // Update status
+        const statusEl = document.getElementById('qrScannerStatus');
+        if (statusEl) {
+            statusEl.innerHTML = '<i class="bi bi-check-circle text-success me-2"></i>QR code detected!';
+            statusEl.className = 'text-center py-3 text-success';
+        }
+
+        // Close modal after brief delay
+        setTimeout(() => {
+            this._qrScannerModal?.hide();
+
+            // Call callback
+            if (this._qrScannerCallback) {
+                this._qrScannerCallback(text);
+            }
+        }, 500);
+    },
+
+    /**
+     * Add camera scan button to an input field
+     * @param {string} inputId - ID of the input field
+     * @param {string} title - Modal title
+     * @param {Function} validator - Optional validation function for scanned text
+     */
+    addCameraScanButton(inputId, title = 'Scan QR Code', validator = null) {
+        const input = document.getElementById(inputId);
+        if (!input) return;
+
+        // Create button
+        const btn = document.createElement('button');
+        btn.type = 'button';
+        btn.className = 'btn btn-outline-secondary';
+        btn.innerHTML = '<i class="bi bi-camera"></i>';
+        btn.title = 'Scan QR code with camera';
+
+        btn.addEventListener('click', () => {
+            this.showQrScanner((text) => {
+                // Validate if validator provided
+                if (validator && !validator(text)) {
+                    alert('Invalid QR code format');
+                    return;
+                }
+                // Set input value
+                input.value = text;
+                // Trigger input event for formatting
+                input.dispatchEvent(new Event('input', { bubbles: true }));
+            }, title);
+        });
+
+        // Wrap input in input-group if not already
+        const parent = input.parentElement;
+        if (!parent.classList.contains('input-group')) {
+            const wrapper = document.createElement('div');
+            wrapper.className = 'input-group';
+            parent.insertBefore(wrapper, input);
+            wrapper.appendChild(input);
+            wrapper.appendChild(btn);
+        } else {
+            parent.appendChild(btn);
+        }
     },
 
     // ========================================================================
@@ -1111,6 +1556,39 @@ const Stegasoo = {
             generateBtnId: 'channelKeyGenerate'
         });
 
+        // Webcam QR scanning for channel key (v4.1.5)
+        document.getElementById('channelKeyScan')?.addEventListener('click', () => {
+            this.showQrScanner((text) => {
+                const input = document.getElementById('channelKeyInput');
+                if (input) {
+                    const clean = text.replace(/[^A-Za-z0-9]/g, '').toUpperCase();
+                    input.value = clean.length === 32 ? clean.match(/.{4}/g).join('-') : text.toUpperCase();
+                    input.dispatchEvent(new Event('input', { bubbles: true }));
+                }
+            }, 'Scan Channel Key');
+        });
+
+        // Webcam QR scanning for RSA key (v4.1.5)
+        document.getElementById('rsaQrWebcam')?.addEventListener('click', () => {
+            this.showQrScanner((text) => {
+                // Check for raw PEM or compressed format (STEGASOO-Z: prefix)
+                const isRawPem = text.includes('-----BEGIN') && text.includes('KEY-----');
+                const isCompressed = text.startsWith('STEGASOO-Z:');
+                if (isRawPem || isCompressed) {
+                    // Valid RSA key data scanned
+                    document.getElementById('rsaKeyPem').value = text;
+                    // Show success in drop zone
+                    const dropZone = document.getElementById('qrDropZone');
+                    const label = dropZone?.querySelector('.drop-zone-label');
+                    if (label) {
+                        label.innerHTML = '<i class="bi bi-check-circle text-success fs-4 d-block mb-1"></i><span class="text-success small">RSA Key scanned successfully</span>';
+                    }
+                } else {
+                    alert('QR code does not contain a valid RSA key');
+                }
+            }, 'Scan RSA Key QR');
+        });
+
         // Form submission with async progress tracking (v4.1.2)
         const form = document.getElementById('encodeForm');
         const btn = document.getElementById('encodeBtn');
@@ -1136,7 +1614,7 @@ const Stegasoo = {
         this.initRsaMethodToggle();
         this.initDropZones();
         this.initClipboardPaste(['input[name="stego_image"]', 'input[name="reference_photo"]']);
-        this.initQrCropAnimation('rsaKeyQrInput');
+        this.initQrCropAnimation('rsaQrInput');
         this.initCollapseChevrons();
         this.initPassphraseFontResize();
         
@@ -1148,28 +1626,56 @@ const Stegasoo = {
             serverInfoId: 'channelServerInfoDec'
         });
 
-        // Form submission with channel key validation and mode display
+        // Webcam QR scanning for channel key (v4.1.5)
+        document.getElementById('channelKeyScanDec')?.addEventListener('click', () => {
+            this.showQrScanner((text) => {
+                const input = document.getElementById('channelKeyInputDec');
+                if (input) {
+                    const clean = text.replace(/[^A-Za-z0-9]/g, '').toUpperCase();
+                    input.value = clean.length === 32 ? clean.match(/.{4}/g).join('-') : text.toUpperCase();
+                    input.dispatchEvent(new Event('input', { bubbles: true }));
+                }
+            }, 'Scan Channel Key');
+        });
+
+        // Webcam QR scanning for RSA key (v4.1.5)
+        document.getElementById('rsaQrWebcam')?.addEventListener('click', () => {
+            this.showQrScanner((text) => {
+                // Check for raw PEM or compressed format (STEGASOO-Z: prefix)
+                const isRawPem = text.includes('-----BEGIN') && text.includes('KEY-----');
+                const isCompressed = text.startsWith('STEGASOO-Z:');
+                if (isRawPem || isCompressed) {
+                    // Valid RSA key data scanned
+                    document.getElementById('rsaKeyPem').value = text;
+                    // Show success in drop zone
+                    const dropZone = document.getElementById('qrDropZone');
+                    const label = dropZone?.querySelector('.drop-zone-label');
+                    if (label) {
+                        label.innerHTML = '<i class="bi bi-check-circle text-success fs-4 d-block mb-1"></i><span class="text-success small">RSA Key scanned successfully</span>';
+                    }
+                } else {
+                    alert('QR code does not contain a valid RSA key');
+                }
+            }, 'Scan RSA Key QR');
+        });
+
+        // Form submission with async progress tracking (v4.1.5)
         const form = document.getElementById('decodeForm');
         const btn = document.getElementById('decodeBtn');
         form?.addEventListener('submit', (e) => {
+            e.preventDefault();
+
             if (!this.validateChannelKeyOnSubmit(form, 'channelSelectDec', 'channelKeyInputDec')) {
-                e.preventDefault();
                 return false;
             }
-            const selectedMode = document.querySelector('input[name="embed_mode"]:checked')?.value || 'auto';
+
             if (btn) {
                 btn.disabled = true;
-                const startTime = Date.now();
-                const updateTimer = () => {
-                    const elapsed = Math.floor((Date.now() - startTime) / 1000);
-                    const mins = Math.floor(elapsed / 60);
-                    const secs = elapsed % 60;
-                    const timeStr = mins > 0 ? `${mins}:${secs.toString().padStart(2, '0')}` : `${secs}s`;
-                    btn.innerHTML = `<span class="spinner-border spinner-border-sm me-2"></span>Decoding (${selectedMode.toUpperCase()})... ${timeStr}`;
-                };
-                updateTimer();
-                setInterval(updateTimer, 1000);
+                btn.innerHTML = '<span class="spinner-border spinner-border-sm me-2"></span>Starting...';
             }
+
+            // Use async submission with progress tracking
+            this.submitDecodeAsync(form, btn);
         });
     },
     

frontends/web/static/style.css

@@ -16,7 +16,7 @@
     --overlay-dark: rgba(0, 0, 0, 0.3);
     --overlay-light: rgba(255, 255, 255, 0.05);
     --day-highlight: #E3FF54; /* Bright yellow/green for day of week */
-    --header-gold: #fee862; /* Halfway between light straw and 24k gold */
+    --header-gold: #e5d058; /* Muted gold - less harsh on varied monitors */
 }
 
 /* ----------------------------------------------------------------------------
@@ -91,6 +91,56 @@
     min-width: 0;
 }
 
+/* Compact inline mode buttons */
+.mode-btn.mode-btn-sm {
+    padding: 0.35rem 0.6rem;
+    padding-left: 1.75rem;
+    font-size: 0.8rem;
+    border-radius: 0.375rem;
+    border-width: 1px;
+}
+
+.mode-btn.mode-btn-sm .form-check-input {
+    left: 8px;
+    width: 14px;
+    height: 14px;
+}
+
+.mode-btn.mode-btn-sm i {
+    font-size: 0.85rem;
+}
+
+/* Disabled button labels for btn-check groups */
+.btn-check:disabled + .btn {
+    opacity: 0.4;
+    pointer-events: none;
+}
+
+/* ----------------------------------------------------------------------------
+   Form Labels - Gold
+   ---------------------------------------------------------------------------- */
+.card .form-label {
+    color: #d9c580;
+    font-weight: 400;
+}
+
+/* Dropdown selects - ensure chevron is visible in dark mode */
+.form-select,
+select.form-select {
+    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23d9c580' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e") !important;
+    background-repeat: no-repeat !important;
+    background-position: right 0.75rem center !important;
+    background-size: 16px 12px !important;
+    padding-right: 2.25rem !important;
+}
+
+/* Payload type toggle - gold text when selected */
+.btn-check:checked + .btn-outline-primary {
+    color: #d9c580 !important;
+    font-weight: 500;
+}
+
+
 /* ----------------------------------------------------------------------------
    Security Factor Boxes - Matches drop-zone dashed border style
    ---------------------------------------------------------------------------- */
@@ -125,6 +175,122 @@ body {
 .navbar {
     background: var(--overlay-dark) !important;
     backdrop-filter: blur(10px);
+    z-index: 1030;  /* Above page content for dropdowns */
+}
+
+.navbar > .container {
+    padding-left: 0;
+}
+
+/* Ensure navbar dropdown appears above all page content */
+.navbar .dropdown-menu {
+    z-index: 1031;
+}
+
+/* Left-align collapsed navbar menu on mobile */
+@media (max-width: 991.98px) {
+    .navbar-collapse .navbar-nav {
+        align-items: flex-start !important;
+    }
+}
+
+/* ----------------------------------------------------------------------------
+   Nav Icons - Floating Label on Hover (label floats below, no layout shift)
+   ---------------------------------------------------------------------------- */
+.nav-icons {
+    gap: 0.25rem;
+}
+
+.nav-icons .nav-item {
+    position: relative;
+}
+
+.nav-expand {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    padding: 0.5rem 0.75rem !important;
+    border-radius: 0.5rem;
+    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
+    background: transparent;
+    position: relative;
+}
+
+.nav-expand i {
+    font-size: 1.15rem;
+    transition: all 0.3s ease;
+}
+
+/* Floating label - absolutely positioned below */
+.nav-expand span {
+    position: absolute;
+    top: 100%;
+    left: 50%;
+    transform: translateX(-50%) translateY(-4px);
+    font-size: 0.7rem;
+    font-weight: 500;
+    text-transform: uppercase;
+    letter-spacing: 1px;
+    white-space: nowrap;
+    opacity: 0;
+    pointer-events: none;
+    color: var(--header-gold);
+    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.8);
+    transition: opacity 0.2s ease,
+                transform 0.2s cubic-bezier(0.4, 0, 0.2, 1);
+    z-index: 1040;
+}
+
+.nav-expand:hover {
+    background: linear-gradient(135deg, rgba(74, 40, 96, 0.25) 0%, rgba(85, 112, 212, 0.2) 100%);
+    box-shadow: 0 0 8px rgba(102, 126, 234, 0.15),
+                inset 0 1px 0 rgba(255, 255, 255, 0.1);
+}
+
+.nav-expand:hover i {
+    color: var(--header-gold);
+    filter: drop-shadow(0 0 4px rgba(254, 232, 98, 0.4));
+}
+
+.nav-expand:hover span {
+    opacity: 1;
+    transform: translateX(-50%) translateY(2px);
+}
+
+/* Active state for current page */
+.nav-expand.active,
+.nav-item.active .nav-expand {
+    background: linear-gradient(135deg, rgba(74, 40, 96, 0.6) 0%, rgba(85, 112, 212, 0.5) 100%);
+}
+
+.nav-expand.active i,
+.nav-item.active .nav-expand i {
+    color: var(--header-gold);
+}
+
+/* Mobile: Always show labels inline in collapsed menu */
+@media (max-width: 991.98px) {
+    .nav-expand span {
+        position: static;
+        transform: none;
+        opacity: 1;
+        background: none;
+        box-shadow: none;
+        padding: 0;
+        margin-left: 0.5rem;
+        font-size: 0.9rem;
+        text-transform: none;
+        letter-spacing: normal;
+        pointer-events: auto;
+    }
+
+    .nav-expand:hover span {
+        transform: none;
+    }
+
+    .nav-expand:hover {
+        background: rgba(255, 255, 255, 0.1);
+    }
 }
 
 /* ----------------------------------------------------------------------------
@@ -893,36 +1059,36 @@ footer {
     opacity: 0;
 }
 
-/* Color variants - 60% opacity */
+/* Color variants - 70% opacity with tighter glow for thin lines */
 .embed-trace.color-yellow {
-    background: rgba(212, 225, 87, 0.6);
-    box-shadow: 0 0 6px rgba(212, 225, 87, 0.5), 0 0 12px rgba(212, 225, 87, 0.3);
+    background: rgba(212, 225, 87, 0.7);
+    box-shadow: 0 0 3px rgba(212, 225, 87, 0.6), 0 0 6px rgba(212, 225, 87, 0.3);
 }
 
 .embed-trace.color-cyan {
-    background: rgba(0, 255, 170, 0.6);
-    box-shadow: 0 0 6px rgba(0, 255, 170, 0.5), 0 0 12px rgba(0, 255, 170, 0.3);
+    background: rgba(0, 255, 170, 0.7);
+    box-shadow: 0 0 3px rgba(0, 255, 170, 0.6), 0 0 6px rgba(0, 255, 170, 0.3);
 }
 
 .embed-trace.color-purple {
-    background: rgba(167, 139, 250, 0.6);
-    box-shadow: 0 0 6px rgba(167, 139, 250, 0.5), 0 0 12px rgba(167, 139, 250, 0.3);
+    background: rgba(167, 139, 250, 0.7);
+    box-shadow: 0 0 3px rgba(167, 139, 250, 0.6), 0 0 6px rgba(167, 139, 250, 0.3);
 }
 
 .embed-trace.color-blue {
-    background: rgba(102, 126, 234, 0.6);
-    box-shadow: 0 0 6px rgba(102, 126, 234, 0.5), 0 0 12px rgba(102, 126, 234, 0.3);
+    background: rgba(102, 126, 234, 0.7);
+    box-shadow: 0 0 3px rgba(102, 126, 234, 0.6), 0 0 6px rgba(102, 126, 234, 0.3);
 }
 
 /* Vertical segments shrink from top */
 .embed-trace.v {
-    width: 2px;
+    width: 1px;
     transform-origin: top center;
 }
 
 /* Horizontal segments shrink from left */
 .embed-trace.h {
-    height: 2px;
+    height: 1px;
     transform-origin: left center;
 }
 
@@ -1094,7 +1260,8 @@ footer {
    ---------------------------------------------------------------------------- */
 #rsaQrSection {
     display: flex;
-    justify-content: center;
+    flex-direction: column;
+    align-items: center;
 }
 
 #rsaQrSection .drop-zone {
@@ -1699,3 +1866,459 @@ footer {
         font-size: 3rem;
     }
 }
+
+/* ============================================================================
+   TOOLS PAGE - Office-style Ribbon + Two-Panel Layout
+   ============================================================================ */
+
+/* Icon Toolbar Ribbon - Purple/Blue Gradient Theme */
+.tools-ribbon {
+    display: flex;
+    align-items: center;
+    justify-content: flex-start;
+    gap: 0.5rem;
+    padding: 0.75rem 1rem;
+    background: linear-gradient(135deg, rgba(102, 126, 234, 0.15) 0%, rgba(139, 92, 246, 0.15) 100%);
+    border-bottom: 1px solid rgba(139, 92, 246, 0.2);
+    border-radius: 0.5rem 0.5rem 0 0;
+    flex-wrap: wrap;
+}
+
+.tools-ribbon-group {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+}
+
+.tools-ribbon-divider {
+    width: 2px;
+    height: 32px;
+    background: linear-gradient(180deg, rgba(102, 126, 234, 0.4) 0%, rgba(139, 92, 246, 0.4) 100%);
+    margin: 0 0.75rem;
+    border-radius: 1px;
+}
+
+/* Tool Icon Buttons */
+.tool-icon-btn {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    width: 64px;
+    height: 52px;
+    padding: 0.25rem;
+    border: 1px solid transparent;
+    border-radius: 0.375rem;
+    background: transparent;
+    color: rgba(255, 255, 255, 0.6);
+    cursor: pointer;
+    transition: all 0.2s ease;
+}
+
+.tool-icon-btn i {
+    font-size: 1.25rem;
+    margin-bottom: 2px;
+}
+
+.tool-icon-btn span {
+    font-size: 0.62rem;
+    font-weight: 500;
+    text-transform: uppercase;
+    letter-spacing: 1px;
+}
+
+.tool-icon-btn:hover {
+    background: rgba(255, 230, 150, 0.1);
+    border-color: rgba(255, 230, 150, 0.3);
+    color: var(--header-gold);
+    font-weight: 600;
+    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.33);
+}
+
+.tool-icon-btn.active {
+    background: linear-gradient(135deg, rgba(102, 126, 234, 0.25) 0%, rgba(139, 92, 246, 0.25) 100%);
+    border-color: rgba(139, 92, 246, 0.5);
+    color: #c4b5fd;
+    box-shadow: 0 0 12px rgba(139, 92, 246, 0.2);
+}
+
+/* Two-Panel Layout */
+.tools-panels {
+    display: flex;
+    min-height: 400px;
+    border-radius: 0 0 0.5rem 0.5rem;
+}
+
+/* Left Panel - Input/Dropzone */
+.tools-panel-input {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    background: rgba(0, 0, 0, 0.15);
+    border-right: 1px solid rgba(255, 255, 255, 0.08);
+}
+
+/* Tool Mode Banner - bottom of input panel */
+.tool-mode-banner {
+    margin-top: auto; /* Push to bottom */
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    padding: 0.6rem 1.25rem;
+    background: linear-gradient(135deg, rgba(102, 126, 234, 0.2) 0%, rgba(139, 92, 246, 0.2) 100%);
+    border-top: 1px solid rgba(139, 92, 246, 0.2);
+    font-size: 0.75rem;
+}
+
+.tool-mode-type {
+    text-transform: uppercase;
+    letter-spacing: 1px;
+    font-weight: 600;
+    padding: 0.2rem 0.5rem;
+    border-radius: 3px;
+    background: rgba(139, 92, 246, 0.3);
+    color: #c4b5fd;
+}
+
+.tool-mode-banner.mode-analyze .tool-mode-type {
+    background: rgba(72, 187, 120, 0.3);
+    color: #9ae6b4;
+}
+
+.tool-mode-banner.mode-transform .tool-mode-type {
+    background: rgba(237, 181, 71, 0.3);
+    color: #fbd38d;
+}
+
+.tool-mode-name {
+    color: rgba(255, 255, 255, 0.7);
+    font-weight: 500;
+}
+
+/* Right Panel - Results */
+.tools-panel-results {
+    width: 280px;
+    min-width: 280px;
+    display: flex;
+    flex-direction: column;
+    padding: 1.25rem;
+    background: rgba(0, 0, 0, 0.25);
+}
+
+/* Tool Options Row */
+.tool-options {
+    display: flex;
+    align-items: center;
+    gap: 1rem;
+    margin-bottom: 1rem;
+    padding-bottom: 1rem;
+    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
+    flex-wrap: wrap;
+}
+
+.tool-options:empty {
+    display: none;
+}
+
+.tool-options label {
+    font-size: 0.8rem;
+    color: rgba(255, 255, 255, 0.6);
+    margin-bottom: 0;
+}
+
+.tool-options .form-select,
+.tool-options .form-control {
+    background: rgba(0, 0, 0, 0.3);
+    border-color: rgba(255, 255, 255, 0.15);
+    font-size: 0.85rem;
+    padding: 0.4rem 0.75rem;
+}
+
+/* Tool Drop Zone */
+.tool-dropzone {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    min-height: 200px;
+    border: 2px dashed rgba(255, 255, 255, 0.2);
+    border-radius: 0.5rem;
+    background: rgba(0, 0, 0, 0.15);
+    transition: all 0.3s ease;
+    position: relative;
+    overflow: hidden;
+}
+
+.tool-dropzone input[type="file"] {
+    position: absolute;
+    inset: 0;
+    opacity: 0;
+    cursor: pointer;
+    z-index: 10;
+}
+
+.tool-dropzone-label {
+    text-align: center;
+    color: rgba(255, 255, 255, 0.5);
+}
+
+.tool-dropzone-label i {
+    font-size: 2.5rem;
+    margin-bottom: 0.75rem;
+    display: block;
+    opacity: 0.5;
+}
+
+.tool-dropzone.drag-over {
+    border-color: #63b3ed;
+    background: rgba(99, 179, 237, 0.1);
+}
+
+.tool-dropzone.drag-over .tool-dropzone-label i {
+    color: #63b3ed;
+    opacity: 1;
+}
+
+/* Dropzone with preview */
+.tool-dropzone.has-file .tool-dropzone-label {
+    display: none;
+}
+
+.tool-dropzone-preview {
+    display: none;
+    width: 100%;
+    height: 100%;
+    padding: 1rem;
+}
+
+.tool-dropzone.has-file .tool-dropzone-preview {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+}
+
+.tool-dropzone-preview img {
+    max-width: 100%;
+    max-height: 180px;
+    object-fit: contain;
+    border-radius: 0.375rem;
+    border: 2px solid rgba(99, 179, 237, 0.3);
+}
+
+/* Rotate preview - smooth transitions for size and transform */
+#rotateThumb {
+    transition: transform 0.1s ease-out, width 0.1s ease-out, height 0.1s ease-out;
+}
+
+/* Rotate image container - fixed height to contain rotated images */
+.rotate-img-container {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    min-height: 180px;
+}
+
+/* Rotate file info - separate row below dropzone */
+.rotate-file-info {
+    text-align: center;
+    padding: 0.5rem 0;
+    margin-top: 0.25rem;
+}
+.rotate-file-info .file-name {
+    font-size: 0.85rem;
+    color: #63b3ed;
+    font-weight: 500;
+}
+.rotate-file-info .file-meta {
+    font-size: 0.75rem;
+    color: rgba(255, 255, 255, 0.5);
+}
+
+.tool-dropzone-preview .file-name {
+    margin-top: 0.75rem;
+    font-size: 0.85rem;
+    color: #63b3ed;
+    font-weight: 500;
+}
+
+.tool-dropzone-preview .file-meta {
+    font-size: 0.75rem;
+    color: rgba(255, 255, 255, 0.5);
+}
+
+.tool-dropzone-clear {
+    position: absolute;
+    top: 0.5rem;
+    right: 0.5rem;
+    z-index: 20;
+    opacity: 0.6;
+}
+
+.tool-dropzone-clear:hover {
+    opacity: 1;
+}
+
+/* Results Panel Content */
+.tool-results-header {
+    margin-bottom: 1rem;
+    padding-bottom: 0.75rem;
+    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
+}
+
+.tool-results-header h6 {
+    margin: 0;
+    font-size: 1rem;
+    font-weight: 600;
+    color: #fff;
+}
+
+.tool-results-header small {
+    font-size: 0.75rem;
+    color: rgba(255, 255, 255, 0.5);
+}
+
+.tool-results-body {
+    flex: 1;
+    overflow-y: auto;
+}
+
+.tool-results-empty {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    height: 100%;
+    color: rgba(255, 255, 255, 0.3);
+    text-align: center;
+}
+
+.tool-results-empty i {
+    font-size: 2rem;
+    margin-bottom: 0.5rem;
+}
+
+/* Result Items */
+.tool-result-item {
+    display: flex;
+    justify-content: space-between;
+    align-items: baseline;
+    padding: 0.5rem 0;
+    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
+}
+
+.tool-result-item:last-child {
+    border-bottom: none;
+}
+
+.tool-result-label {
+    font-size: 0.8rem;
+    color: rgba(255, 255, 255, 0.5);
+}
+
+.tool-result-value {
+    font-size: 0.9rem;
+    font-weight: 500;
+    color: #fff;
+    font-family: 'SF Mono', 'Consolas', monospace;
+}
+
+.tool-result-value.text-primary { color: #63b3ed !important; }
+.tool-result-value.text-success { color: #48bb78 !important; }
+.tool-result-value.text-warning { color: #edb547 !important; }
+
+/* Results Actions */
+.tool-results-actions {
+    margin-top: auto;
+    padding-top: 1rem;
+    border-top: 1px solid rgba(255, 255, 255, 0.1);
+    display: flex;
+    gap: 0.5rem;
+}
+
+.tool-results-actions .btn {
+    flex: 1;
+    font-size: 0.85rem;
+}
+
+/* Tool Section Visibility */
+.tool-section {
+    display: none;
+    width: 100%;
+    flex: 1;
+    padding: 1.25rem;
+}
+
+.tool-section.active {
+    display: flex;
+    flex-direction: column;
+}
+
+/* EXIF Table in Results */
+.tool-exif-table {
+    font-size: 0.8rem;
+    max-height: 250px;
+    overflow-y: auto;
+}
+
+.tool-exif-table table {
+    width: 100%;
+}
+
+.tool-exif-table th,
+.tool-exif-table td {
+    padding: 0.35rem 0.5rem;
+    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
+}
+
+.tool-exif-table th {
+    font-weight: 500;
+    color: rgba(255, 255, 255, 0.5);
+    text-align: left;
+    width: 40%;
+}
+
+.tool-exif-table td {
+    font-family: 'SF Mono', 'Consolas', monospace;
+    word-break: break-all;
+}
+
+/* Loading State */
+.tool-loading {
+    position: absolute;
+    inset: 0;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    background: rgba(0, 0, 0, 0.7);
+    z-index: 30;
+    border-radius: 0.5rem;
+}
+
+/* Mobile Responsive */
+@media (max-width: 768px) {
+    .tools-panels {
+        flex-direction: column;
+    }
+
+    .tools-panel-results {
+        width: 100%;
+        min-width: 100%;
+        border-right: none;
+        border-top: 1px solid rgba(255, 255, 255, 0.08);
+    }
+
+    .tools-ribbon {
+        justify-content: center;
+    }
+
+    .tool-icon-btn {
+        width: 48px;
+        height: 44px;
+    }
+
+    .tool-icon-btn span {
+        display: none;
+    }
+}

frontends/web/stego_worker.py

@@ -3,7 +3,7 @@
 Stegasoo Subprocess Worker (v4.0.0)
 
 This script runs in a subprocess and handles encode/decode operations.
-If it crashes due to jpegio/scipy issues, the parent Flask process survives.
+If it crashes due to jpeglib/scipy issues, the parent Flask process survives.
 
 CHANGES in v4.0.0:
 - Added channel_key support for encode/decode operations
@@ -136,14 +136,33 @@ def encode_operation(params: dict) -> dict:
     }
 
 
+def _write_decode_progress(progress_file: str | None, percent: int, phase: str) -> None:
+    """Write decode progress to file."""
+    if not progress_file:
+        return
+    try:
+        import json
+        with open(progress_file, "w") as f:
+            json.dump({"percent": percent, "phase": phase}, f)
+    except Exception:
+        pass  # Best effort
+
+
 def decode_operation(params: dict) -> dict:
     """Handle decode operation."""
     from stegasoo import decode
 
+    progress_file = params.get("progress_file")
+
+    # Progress: starting
+    _write_decode_progress(progress_file, 5, "reading")
+
     # Decode base64 inputs
     stego_data = base64.b64decode(params["stego_b64"])
     reference_data = base64.b64decode(params["reference_b64"])
 
+    _write_decode_progress(progress_file, 15, "reading")
+
     # Optional RSA key
     rsa_key_data = None
     if params.get("rsa_key_b64"):
@@ -152,6 +171,7 @@ def decode_operation(params: dict) -> dict:
     # Resolve channel key (v4.0.0)
     resolved_channel_key = _resolve_channel_key(params.get("channel_key", "auto"))
 
+    # Library handles progress internally via progress_file parameter
     # Call decode with correct parameter names
     result = decode(
         stego_image=stego_data,
@@ -162,7 +182,9 @@ def decode_operation(params: dict) -> dict:
         rsa_password=params.get("rsa_password"),
         embed_mode=params.get("embed_mode", "auto"),
         channel_key=resolved_channel_key,  # v4.0.0
+        progress_file=progress_file,  # v4.2.0: pass through for real-time progress
     )
+    # Library writes 100% "complete" - no need for worker to write again
 
     if result.is_file:
         return {

frontends/web/subprocess_stego.py

@@ -132,7 +132,7 @@ class SubprocessStego:
     """
     Subprocess-isolated steganography operations.
 
-    All operations run in a separate Python process. If jpegio or scipy
+    All operations run in a separate Python process. If jpeglib or scipy
     crashes, only the subprocess dies - Flask keeps running.
     """
 
@@ -314,6 +314,8 @@ class SubprocessStego:
         # Channel key (v4.0.0)
         channel_key: str | None = "auto",
         timeout: int | None = None,
+        # Progress tracking (v4.1.5)
+        progress_file: str | None = None,
     ) -> DecodeResult:
         """
         Decode a message or file from a stego image.
@@ -328,6 +330,7 @@ class SubprocessStego:
             embed_mode: 'auto', 'lsb', or 'dct'
             channel_key: 'auto' (server config), 'none' (public), or explicit key (v4.0.0)
             timeout: Operation timeout in seconds
+            progress_file: Path to write progress updates (v4.1.5)
 
         Returns:
             DecodeResult with message or file_data on success
@@ -340,6 +343,7 @@ class SubprocessStego:
             "pin": pin,
             "embed_mode": embed_mode,
             "channel_key": channel_key,  # v4.0.0
+            "progress_file": progress_file,  # v4.1.5
         }
 
         if rsa_key_data:

frontends/web/temp_storage.py

@@ -14,8 +14,6 @@ It does NOT touch instance/ (auth database) or any other directories.
 """
 
 import json
-import os
-import shutil
 import time
 from pathlib import Path
 from threading import Lock

frontends/web/templates/about.html

@@ -271,8 +271,7 @@
                             <div class="card-body">
                                 <p class="small mb-2">Uses server-configured key if available, otherwise public mode.</p>
                                 <ul class="small mb-0">
-                                    <li>Set via <code>STEGASOO_CHANNEL_KEY</code> env var</li>
-                                    <li>Or <code>channel_key</code> in config file</li>
+                                    <li>Server admin configures the shared key</li>
                                     <li>All users share the same channel</li>
                                 </ul>
                             </div>
@@ -317,58 +316,18 @@
                 </div>
                 
                 {% if channel_configured %}
-                <div class="alert alert-success mt-3 mb-3">
+                <div class="alert alert-success mt-3 mb-0">
                     <i class="bi bi-shield-lock me-2"></i>
                     <strong>This server has a channel key configured:</strong>
                     <code class="ms-2">{{ channel_fingerprint }}</code>
-                    <span class="text-muted ms-2">({{ channel_source }})</span>
                 </div>
                 {% else %}
-                <div class="alert alert-info mt-3 mb-3">
+                <div class="alert alert-info mt-3 mb-0">
                     <i class="bi bi-info-circle me-2"></i>
                     This server is running in <strong>public mode</strong>.
                     Set <code>STEGASOO_CHANNEL_KEY</code> to enable server-wide channel isolation.
                 </div>
                 {% endif %}
-
-                <!-- Channel Key QR Generator (Admin only) -->
-                {% if is_admin %}
-                <div class="card bg-dark border-secondary">
-                    <div class="card-header">
-                        <i class="bi bi-qr-code me-2"></i>Share Channel Key via QR
-                        <span class="badge bg-warning text-dark ms-2"><i class="bi bi-shield-check me-1"></i>Admin</span>
-                    </div>
-                    <div class="card-body">
-                        <p class="small text-muted mb-3">Generate a QR code to share a channel key with others.</p>
-                        <div class="row g-2 align-items-end">
-                            <div class="col-md-8">
-                                <label class="form-label small">Channel Key</label>
-                                <div class="input-group">
-                                    <input type="text" class="form-control font-monospace" id="channelKeyQrInput"
-                                           placeholder="Enter or generate a key">
-                                    <button class="btn btn-outline-secondary" type="button" id="channelKeyQrGenerate"
-                                            title="Generate random key">
-                                        <i class="bi bi-shuffle"></i>
-                                    </button>
-                                </div>
-                            </div>
-                            <div class="col-md-4">
-                                <button class="btn btn-primary w-100" type="button" id="channelKeyQrShow">
-                                    <i class="bi bi-qr-code me-1"></i>Show QR
-                                </button>
-                            </div>
-                        </div>
-                        <div class="text-center mt-3 d-none" id="channelKeyQrContainer">
-                            <canvas id="channelKeyQrCanvas" class="bg-white p-2 rounded"></canvas>
-                            <div class="mt-2">
-                                <button class="btn btn-sm btn-outline-secondary" type="button" id="channelKeyQrDownload">
-                                    <i class="bi bi-download me-1"></i>Download PNG
-                                </button>
-                            </div>
-                        </div>
-                    </div>
-                </div>
-                {% endif %}
             </div>
         </div>
         
@@ -381,11 +340,13 @@
                 <!-- Current Version - Prominent -->
                 <div class="alert alert-success mb-4">
                     <div class="d-flex align-items-center">
-                        <span class="badge bg-success fs-6 me-3">v4.1.2</span>
+                        <span class="badge bg-success fs-6 me-3">v4.2.0</span>
                         <div>
-                            <strong>Progress bars</strong> for encode operations,
-                            <strong>mobile-responsive polish</strong>,
-                            DCT decode bug fix, release validation script
+                            <strong>Performance optimizations:</strong>
+                            ~70% faster decode (vectorized DCT),
+                            50% less RAM (float32),
+                            async API endpoints,
+                            decode progress callbacks
                         </div>
                     </div>
                 </div>
@@ -403,6 +364,10 @@
                             <div class="accordion-body p-0">
                                 <table class="table table-dark table-sm small mb-0">
                                     <tbody>
+                                        <tr>
+                                            <td width="80"><strong>4.1.7</strong></td>
+                                            <td>Progress bars for encode, mobile polish, release validation</td>
+                                        </tr>
                                         <tr>
                                             <td width="80"><strong>4.1.1</strong></td>
                                             <td>DCT RS format stability, Docker cleanup, first-boot wizard</td>
@@ -600,7 +565,7 @@
                                         </tr>
                                         <tr>
                                             <td><i class="bi bi-clock me-2"></i>File expiry</td>
-                                            <td><strong>5 min</strong></td>
+                                            <td><strong>10 min</strong></td>
                                         </tr>
                                         <tr>
                                             <td><i class="bi bi-key me-2"></i>PIN</td>
@@ -608,7 +573,7 @@
                                         </tr>
                                         <tr>
                                             <td><i class="bi bi-shield me-2"></i>RSA keys</td>
-                                            <td><strong>2048, 3072, 4096 bit</strong></td>
+                                            <td><strong>2048, 3072 bit</strong></td>
                                         </tr>
                                         <tr>
                                             <td><i class="bi bi-chat-quote me-2"></i>Passphrase</td>
@@ -635,62 +600,3 @@
 </div>
 {% endblock %}
 
-{% block scripts %}
-<!-- QR Code library for channel key sharing -->
-<script src="https://cdn.jsdelivr.net/npm/qrcode@1.5.3/build/qrcode.min.js"></script>
-<script src="{{ url_for('static', filename='js/stegasoo.js') }}"></script>
-<script>
-document.addEventListener('DOMContentLoaded', function() {
-    const input = document.getElementById('channelKeyQrInput');
-    const generateBtn = document.getElementById('channelKeyQrGenerate');
-    const showBtn = document.getElementById('channelKeyQrShow');
-    const container = document.getElementById('channelKeyQrContainer');
-    const canvas = document.getElementById('channelKeyQrCanvas');
-    const downloadBtn = document.getElementById('channelKeyQrDownload');
-
-    // Generate random key
-    generateBtn?.addEventListener('click', function() {
-        if (input && typeof Stegasoo !== 'undefined') {
-            input.value = Stegasoo.generateChannelKey();
-        }
-    });
-
-    // Show QR code
-    showBtn?.addEventListener('click', function() {
-        const key = input?.value?.trim().replace(/-/g, '');
-        if (!key || key.length !== 32) {
-            alert('Please enter a valid 32-character channel key');
-            return;
-        }
-
-        // Format key with dashes for QR
-        const formatted = key.match(/.{4}/g)?.join('-') || key;
-
-        // Generate QR code
-        if (typeof QRCode !== 'undefined' && canvas) {
-            QRCode.toCanvas(canvas, formatted, {
-                width: 200,
-                margin: 2,
-                color: { dark: '#000', light: '#fff' }
-            }, function(error) {
-                if (error) {
-                    console.error('QR generation error:', error);
-                    return;
-                }
-                container?.classList.remove('d-none');
-            });
-        }
-    });
-
-    // Download QR as PNG
-    downloadBtn?.addEventListener('click', function() {
-        if (canvas) {
-            const link = document.createElement('a');
-            link.download = 'stegasoo-channel-key.png';
-            link.href = canvas.toDataURL('image/png');
-            link.click();
-        }
-    });
-});
-</script>
-{% endblock %}

frontends/web/templates/account.html

@@ -177,9 +177,16 @@
                                    placeholder="Key name" required maxlength="50">
                         </div>
                         <div class="col-7">
-                            <input type="text" name="channel_key" class="form-control form-control-sm font-monospace"
-                                   placeholder="Channel key (32 hex chars)" required
-                                   pattern="[0-9a-fA-F\-]{32,39}" title="32 hex characters">
+                            <div class="input-group input-group-sm">
+                                <input type="text" name="channel_key" id="channelKeyInput"
+                                       class="form-control font-monospace"
+                                       placeholder="XXXX-XXXX-..." required
+                                       pattern="[A-Za-z0-9]{4}(-[A-Za-z0-9]{4}){7}">
+                                <button type="button" class="btn btn-outline-secondary" id="scanChannelKeyBtn"
+                                        title="Scan QR code with camera">
+                                    <i class="bi bi-camera"></i>
+                                </button>
+                            </div>
                         </div>
                     </div>
                     <button type="submit" class="btn btn-sm btn-outline-primary">
@@ -243,7 +250,10 @@
             </div>
             <div class="modal-footer justify-content-center">
                 <button type="button" class="btn btn-sm btn-outline-secondary" id="qrDownload">
-                    <i class="bi bi-download me-1"></i>Download PNG
+                    <i class="bi bi-download me-1"></i>Download
+                </button>
+                <button type="button" class="btn btn-sm btn-outline-secondary" id="qrPrint">
+                    <i class="bi bi-printer me-1"></i>Print Sheet
                 </button>
             </div>
         </div>
@@ -254,12 +264,34 @@
 
 {% block scripts %}
 <script src="{{ url_for('static', filename='js/auth.js') }}"></script>
+<script src="{{ url_for('static', filename='js/stegasoo.js') }}"></script>
 {% if is_admin %}
-<script src="https://cdn.jsdelivr.net/npm/qrcode@1.5.3/build/qrcode.min.js"></script>
+<script src="{{ url_for('static', filename='js/qrcode.min.js') }}"></script>
 {% endif %}
 <script>
 StegasooAuth.initPasswordConfirmation('accountForm', 'newPasswordInput', 'newPasswordConfirmInput');
 
+// Webcam QR scanning for channel key input (v4.1.5)
+document.getElementById('scanChannelKeyBtn')?.addEventListener('click', function() {
+    Stegasoo.showQrScanner((text) => {
+        const input = document.getElementById('channelKeyInput');
+        if (input) {
+            // Clean and format the key
+            const clean = text.replace(/[^A-Za-z0-9]/g, '').toUpperCase();
+            if (clean.length === 32) {
+                input.value = clean.match(/.{4}/g).join('-');
+            } else {
+                input.value = text.toUpperCase();
+            }
+        }
+    }, 'Scan Channel Key');
+});
+
+// Format channel key input as user types
+document.getElementById('channelKeyInput')?.addEventListener('input', function() {
+    Stegasoo.formatChannelKeyInput(this);
+});
+
 function renameKey(keyId, currentName) {
     document.getElementById('renameInput').value = currentName;
     document.getElementById('renameForm').action = '/account/keys/' + keyId + '/rename';
@@ -276,20 +308,20 @@ function showKeyQr(channelKey, keyName) {
     document.getElementById('qrKeyName').textContent = keyName;
     document.getElementById('qrKeyDisplay').textContent = formatted;
 
-    // Generate QR code
+    // Generate QR code using QRious
     const canvas = document.getElementById('qrCanvas');
-    if (typeof QRCode !== 'undefined' && canvas) {
-        QRCode.toCanvas(canvas, formatted, {
-            width: 200,
-            margin: 2,
-            color: { dark: '#000', light: '#fff' }
-        }, function(error) {
-            if (error) {
-                console.error('QR generation error:', error);
-                return;
-            }
+    if (typeof QRious !== 'undefined' && canvas) {
+        try {
+            new QRious({
+                element: canvas,
+                value: formatted,
+                size: 200,
+                level: 'M'
+            });
             new bootstrap.Modal(document.getElementById('qrModal')).show();
-        });
+        } catch (error) {
+            console.error('QR generation error:', error);
+        }
     }
 }
 
@@ -304,6 +336,105 @@ document.getElementById('qrDownload')?.addEventListener('click', function() {
         link.click();
     }
 });
+
+// Print tiled QR sheet (US Letter)
+document.getElementById('qrPrint')?.addEventListener('click', function() {
+    const canvas = document.getElementById('qrCanvas');
+    const keyText = document.getElementById('qrKeyDisplay').textContent;
+    const keyName = document.getElementById('qrKeyName').textContent;
+    if (canvas && keyText) {
+        printQrSheet(canvas, keyText, keyName);
+    }
+});
+
+// Print QR codes tiled on US Letter paper (8.5" x 11")
+function printQrSheet(canvas, keyText, title) {
+    const qrDataUrl = canvas.toDataURL('image/png');
+    const printWindow = window.open('', '_blank');
+    if (!printWindow) {
+        alert('Please allow popups to print');
+        return;
+    }
+
+    // US Letter: 8.5" x 11" - create 4x5 grid of QR codes
+    const cols = 4;
+    const rows = 5;
+
+    // Split key into two lines (4 groups each)
+    const keyParts = keyText.split('-');
+    const keyLine1 = keyParts.slice(0, 4).join('-');
+    const keyLine2 = keyParts.slice(4).join('-');
+
+    let qrGrid = '';
+    for (let i = 0; i < rows * cols; i++) {
+        qrGrid += `
+            <div class="qr-tile">
+                <div class="key-text">${keyLine1}</div>
+                <img src="${qrDataUrl}" alt="QR">
+                <div class="key-text">${keyLine2}</div>
+            </div>
+        `;
+    }
+
+    printWindow.document.write(`
+        <!DOCTYPE html>
+        <html>
+        <head>
+            <title></title>
+            <style>
+                @page {
+                    size: letter;
+                    margin: 0.2in;
+                    margin-top: 0.1in;
+                    margin-bottom: 0.1in;
+                }
+                @media print {
+                    @page { margin: 0.15in; }
+                    html, body { margin: 0; padding: 0; }
+                }
+                * { margin: 0; padding: 0; box-sizing: border-box; }
+                body {
+                    font-family: 'Courier New', monospace;
+                    background: white;
+                }
+                .grid {
+                    display: grid;
+                    grid-template-columns: repeat(${cols}, 1fr);
+                    gap: 0;
+                    margin-top: 0.09in;
+                }
+                .qr-tile {
+                    border: 1px dashed #ccc;
+                    padding: 0.04in;
+                    text-align: center;
+                    page-break-inside: avoid;
+                }
+                .qr-tile img {
+                    width: 1.6in;
+                    height: 1.6in;
+                }
+                .key-text {
+                    font-size: 10pt;
+                    font-weight: bold;
+                    color: #333;
+                    line-height: 1.2;
+                }
+                .footer {
+                    display: none;
+                }
+            </style>
+        </head>
+        <body>
+            <div class="grid">${qrGrid}</div>
+            <div class="footer">Cut along dashed lines</div>
+            <script>
+                window.onload = function() { window.print(); };
+            <\/script>
+        </body>
+        </html>
+    `);
+    printWindow.document.close();
+}
 {% endif %}
 </script>
 {% endblock %}

frontends/web/templates/admin/settings.html

@@ -0,0 +1,506 @@
+{% extends "base.html" %}
+
+{% block title %}System Settings - Stegasoo{% endblock %}
+
+{% block content %}
+<div class="row justify-content-center">
+    <div class="col-lg-10">
+        <!-- Channel Key Configuration -->
+        <div class="card mb-4">
+            <div class="card-header">
+                <h5 class="mb-0"><i class="bi bi-broadcast me-2"></i>Channel Key Configuration</h5>
+            </div>
+            <div class="card-body">
+                {% if channel_configured %}
+                <div class="alert alert-success mb-4">
+                    <i class="bi bi-shield-lock me-2"></i>
+                    <strong>Server channel key active:</strong>
+                    <code class="ms-2">{{ channel_fingerprint }}</code>
+                    <span class="text-muted ms-2">({{ channel_source }})</span>
+                </div>
+                {% else %}
+                <div class="alert alert-info mb-4">
+                    <i class="bi bi-info-circle me-2"></i>
+                    Server running in <strong>public mode</strong>.
+                    Set <code>STEGASOO_CHANNEL_KEY</code> environment variable to enable server-wide channel isolation.
+                </div>
+                {% endif %}
+
+                <!-- QR Code Generator -->
+                <div class="card bg-dark border-secondary">
+                    <div class="card-header">
+                        <i class="bi bi-qr-code me-2"></i>Share Channel Key via QR
+                    </div>
+                    <div class="card-body">
+                        <p class="small text-muted mb-3">Generate a QR code to share a channel key with others.</p>
+
+                        <!-- Locked state - requires password -->
+                        <div id="channelKeyLocked">
+                            <div class="row g-2 align-items-end">
+                                <div class="col-md-8">
+                                    <label class="form-label small">Channel Key</label>
+                                    <div class="input-group">
+                                        <input type="password" class="form-control font-monospace"
+                                               value="********************************" disabled>
+                                        <span class="input-group-text"><i class="bi bi-lock"></i></span>
+                                    </div>
+                                </div>
+                                <div class="col-md-4">
+                                    <button class="btn btn-warning w-100" type="button" id="channelKeyUnlock">
+                                        <i class="bi bi-unlock me-1"></i>Unlock
+                                    </button>
+                                </div>
+                            </div>
+                            <small class="text-muted mt-2 d-block">
+                                <i class="bi bi-shield-lock me-1"></i>Re-enter your password to view or export the channel key.
+                            </small>
+                        </div>
+
+                        <!-- Unlocked state - shows key and QR options -->
+                        <div id="channelKeyUnlocked" style="display: none;">
+                            <div class="row g-2 align-items-end">
+                                <div class="col-md-8">
+                                    <label class="form-label small">Channel Key</label>
+                                    <div class="input-group">
+                                        <input type="text" class="form-control font-monospace" id="channelKeyQrInput"
+                                               placeholder="Enter or generate a key">
+                                        <button class="btn btn-outline-secondary" type="button" id="channelKeyQrGenerate"
+                                                title="Generate random key">
+                                            <i class="bi bi-shuffle"></i>
+                                        </button>
+                                    </div>
+                                </div>
+                                <div class="col-md-4">
+                                    <button class="btn btn-primary w-100" type="button" id="channelKeyQrShow">
+                                        <i class="bi bi-qr-code me-1"></i>Show QR
+                                    </button>
+                                </div>
+                            </div>
+                            <small class="text-success mt-2 d-block">
+                                <i class="bi bi-unlock me-1"></i>Unlocked for this session.
+                            </small>
+                        </div>
+                    </div>
+                </div>
+            </div>
+        </div>
+
+        <!-- Server Configuration -->
+        <div class="card mb-4">
+            <div class="card-header">
+                <h5 class="mb-0"><i class="bi bi-gear me-2"></i>Server Configuration</h5>
+            </div>
+            <div class="card-body">
+                <div class="row">
+                    <div class="col-md-6">
+                        <table class="table table-dark table-sm">
+                            <tbody>
+                                <tr>
+                                    <td><i class="bi bi-hdd-network me-2"></i>Hostname</td>
+                                    <td><code>{{ hostname }}</code></td>
+                                </tr>
+                                <tr>
+                                    <td><i class="bi bi-ethernet me-2"></i>Port</td>
+                                    <td><code>{{ port }}</code></td>
+                                </tr>
+                                <tr>
+                                    <td><i class="bi bi-shield-lock me-2"></i>HTTPS</td>
+                                    <td>
+                                        {% if https_enabled %}
+                                        <span class="badge bg-success"><i class="bi bi-lock me-1"></i>Enabled</span>
+                                        {% else %}
+                                        <span class="badge bg-warning text-dark"><i class="bi bi-unlock me-1"></i>Disabled</span>
+                                        {% endif %}
+                                    </td>
+                                </tr>
+                                <tr>
+                                    <td><i class="bi bi-person-lock me-2"></i>Authentication</td>
+                                    <td>
+                                        {% if auth_enabled %}
+                                        <span class="badge bg-success"><i class="bi bi-check me-1"></i>Enabled</span>
+                                        {% else %}
+                                        <span class="badge bg-danger"><i class="bi bi-x me-1"></i>Disabled</span>
+                                        {% endif %}
+                                    </td>
+                                </tr>
+                            </tbody>
+                        </table>
+                    </div>
+                    <div class="col-md-6">
+                        <table class="table table-dark table-sm">
+                            <tbody>
+                                <tr>
+                                    <td><i class="bi bi-file-earmark me-2"></i>Max Payload</td>
+                                    <td><code>{{ max_payload_kb }} KB</code></td>
+                                </tr>
+                                <tr>
+                                    <td><i class="bi bi-upload me-2"></i>Max Upload</td>
+                                    <td><code>{{ max_upload_mb }} MB</code></td>
+                                </tr>
+                                <tr>
+                                    <td><i class="bi bi-soundwave me-2"></i>DCT Mode</td>
+                                    <td>
+                                        {% if dct_available %}
+                                        <span class="badge bg-success"><i class="bi bi-check me-1"></i>Available</span>
+                                        {% else %}
+                                        <span class="badge bg-secondary">Not Available</span>
+                                        {% endif %}
+                                    </td>
+                                </tr>
+                                <tr>
+                                    <td><i class="bi bi-qr-code me-2"></i>QR Support</td>
+                                    <td>
+                                        {% if qr_available %}
+                                        <span class="badge bg-success"><i class="bi bi-check me-1"></i>Available</span>
+                                        {% else %}
+                                        <span class="badge bg-secondary">Not Available</span>
+                                        {% endif %}
+                                    </td>
+                                </tr>
+                            </tbody>
+                        </table>
+                    </div>
+                </div>
+
+                <div class="alert alert-secondary small mt-3 mb-0">
+                    <i class="bi bi-info-circle me-2"></i>
+                    To change server settings, edit environment variables or config file and restart the service.
+                    <br>See <code>STEGASOO_HTTPS_ENABLED</code>, <code>STEGASOO_PORT</code>, <code>STEGASOO_CHANNEL_KEY</code>
+                </div>
+            </div>
+        </div>
+
+        <!-- Environment Info -->
+        <div class="card mb-4">
+            <div class="card-header">
+                <h5 class="mb-0"><i class="bi bi-info-circle me-2"></i>Environment</h5>
+            </div>
+            <div class="card-body">
+                <div class="row text-center">
+                    <div class="col-6 col-md-3 mb-3">
+                        <div class="p-3 bg-dark rounded h-100">
+                            <i class="bi bi-box text-primary fs-3 d-block mb-2"></i>
+                            <div class="small text-muted">Version</div>
+                            <strong>{{ version }}</strong>
+                        </div>
+                    </div>
+                    <div class="col-6 col-md-3 mb-3">
+                        <div class="p-3 bg-dark rounded h-100">
+                            <i class="bi bi-terminal text-info fs-3 d-block mb-2"></i>
+                            <div class="small text-muted">Python</div>
+                            <strong>{{ python_version }}</strong>
+                        </div>
+                    </div>
+                    <div class="col-6 col-md-3 mb-3">
+                        <div class="p-3 bg-dark rounded h-100">
+                            <i class="bi bi-cpu text-warning fs-3 d-block mb-2"></i>
+                            <div class="small text-muted">Platform</div>
+                            <strong>{{ platform }}</strong>
+                        </div>
+                    </div>
+                    <div class="col-6 col-md-3 mb-3">
+                        <div class="p-3 bg-dark rounded h-100">
+                            <i class="bi bi-shield-check text-success fs-3 d-block mb-2"></i>
+                            <div class="small text-muted">KDF</div>
+                            <strong>{{ kdf_type }}</strong>
+                        </div>
+                    </div>
+                </div>
+            </div>
+        </div>
+    </div>
+</div>
+
+<!-- Password Verification Modal -->
+<div class="modal fade" id="passwordModal" tabindex="-1">
+    <div class="modal-dialog modal-sm modal-dialog-centered">
+        <div class="modal-content">
+            <div class="modal-header">
+                <h6 class="modal-title"><i class="bi bi-shield-lock me-2"></i>Verify Password</h6>
+                <button type="button" class="btn-close" data-bs-dismiss="modal"></button>
+            </div>
+            <div class="modal-body">
+                <p class="small text-muted mb-3">Re-enter your password to access sensitive data.</p>
+                <div class="mb-3">
+                    <label class="form-label small">Password</label>
+                    <input type="password" class="form-control" id="verifyPassword" autocomplete="current-password">
+                    <div class="invalid-feedback" id="passwordError">Incorrect password</div>
+                </div>
+            </div>
+            <div class="modal-footer">
+                <button type="button" class="btn btn-secondary btn-sm" data-bs-dismiss="modal">Cancel</button>
+                <button type="button" class="btn btn-warning btn-sm" id="verifyPasswordBtn">
+                    <i class="bi bi-unlock me-1"></i>Unlock
+                </button>
+            </div>
+        </div>
+    </div>
+</div>
+
+<!-- QR Code Modal -->
+<div class="modal fade" id="channelKeyQrModal" tabindex="-1">
+    <div class="modal-dialog modal-sm modal-dialog-centered">
+        <div class="modal-content">
+            <div class="modal-header">
+                <h6 class="modal-title"><i class="bi bi-qr-code me-2"></i>Channel Key</h6>
+                <button type="button" class="btn-close" data-bs-dismiss="modal"></button>
+            </div>
+            <div class="modal-body text-center">
+                <canvas id="channelKeyQrCanvas" class="bg-white p-2 rounded"></canvas>
+                <div class="mt-2">
+                    <code class="small" id="channelKeyQrDisplay"></code>
+                </div>
+            </div>
+            <div class="modal-footer justify-content-center">
+                <button type="button" class="btn btn-sm btn-outline-secondary" id="channelKeyQrDownload">
+                    <i class="bi bi-download me-1"></i>Download
+                </button>
+                <button type="button" class="btn btn-sm btn-outline-secondary" id="channelKeyQrPrint">
+                    <i class="bi bi-printer me-1"></i>Print Sheet
+                </button>
+            </div>
+        </div>
+    </div>
+</div>
+{% endblock %}
+
+{% block scripts %}
+<script src="{{ url_for('static', filename='js/qrcode.min.js') }}"></script>
+<script src="{{ url_for('static', filename='js/stegasoo.js') }}"></script>
+<script>
+document.addEventListener('DOMContentLoaded', function() {
+    const input = document.getElementById('channelKeyQrInput');
+    const generateBtn = document.getElementById('channelKeyQrGenerate');
+    const showBtn = document.getElementById('channelKeyQrShow');
+    const canvas = document.getElementById('channelKeyQrCanvas');
+    const displayEl = document.getElementById('channelKeyQrDisplay');
+    const downloadBtn = document.getElementById('channelKeyQrDownload');
+    const modalEl = document.getElementById('channelKeyQrModal');
+    const modal = modalEl ? new bootstrap.Modal(modalEl) : null;
+
+    // Password verification elements
+    const lockedDiv = document.getElementById('channelKeyLocked');
+    const unlockedDiv = document.getElementById('channelKeyUnlocked');
+    const unlockBtn = document.getElementById('channelKeyUnlock');
+    const passwordModalEl = document.getElementById('passwordModal');
+    const passwordModal = passwordModalEl ? new bootstrap.Modal(passwordModalEl) : null;
+    const verifyPasswordInput = document.getElementById('verifyPassword');
+    const verifyPasswordBtn = document.getElementById('verifyPasswordBtn');
+    const passwordError = document.getElementById('passwordError');
+
+    // Unlock button shows password modal
+    unlockBtn?.addEventListener('click', function() {
+        verifyPasswordInput.value = '';
+        verifyPasswordInput.classList.remove('is-invalid');
+        passwordModal?.show();
+        setTimeout(() => verifyPasswordInput.focus(), 300);
+    });
+
+    // Handle Enter key in password field
+    verifyPasswordInput?.addEventListener('keypress', function(e) {
+        if (e.key === 'Enter') {
+            e.preventDefault();
+            verifyPasswordBtn?.click();
+        }
+    });
+
+    // Verify password and unlock
+    verifyPasswordBtn?.addEventListener('click', async function() {
+        const password = verifyPasswordInput.value;
+        if (!password) {
+            verifyPasswordInput.classList.add('is-invalid');
+            return;
+        }
+
+        verifyPasswordBtn.disabled = true;
+        verifyPasswordBtn.innerHTML = '<span class="spinner-border spinner-border-sm me-1"></span>Verifying...';
+
+        try {
+            const response = await fetch('/admin/settings/unlock', {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/json',
+                    'X-Requested-With': 'XMLHttpRequest'
+                },
+                body: JSON.stringify({ password })
+            });
+
+            const data = await response.json();
+
+            if (data.success) {
+                // Unlock successful
+                passwordModal?.hide();
+                lockedDiv.style.display = 'none';
+                unlockedDiv.style.display = 'block';
+                if (data.channel_key && input) {
+                    input.value = data.channel_key;
+                }
+            } else {
+                // Password incorrect
+                verifyPasswordInput.classList.add('is-invalid');
+                passwordError.textContent = data.error || 'Incorrect password';
+            }
+        } catch (error) {
+            verifyPasswordInput.classList.add('is-invalid');
+            passwordError.textContent = 'Verification failed';
+        } finally {
+            verifyPasswordBtn.disabled = false;
+            verifyPasswordBtn.innerHTML = '<i class="bi bi-unlock me-1"></i>Unlock';
+        }
+    });
+
+    // Generate random key
+    generateBtn?.addEventListener('click', function() {
+        if (!input) return;
+        if (typeof Stegasoo !== 'undefined' && Stegasoo.generateChannelKey) {
+            input.value = Stegasoo.generateChannelKey();
+        } else {
+            const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
+            let key = '';
+            for (let i = 0; i < 8; i++) {
+                if (i > 0) key += '-';
+                for (let j = 0; j < 4; j++) {
+                    key += chars.charAt(Math.floor(Math.random() * chars.length));
+                }
+            }
+            input.value = key;
+        }
+    });
+
+    // Show QR code in modal
+    showBtn?.addEventListener('click', function() {
+        const key = input?.value?.trim().replace(/-/g, '');
+        if (!key || key.length !== 32) {
+            alert('Please enter a valid 32-character channel key');
+            return;
+        }
+
+        const formatted = key.match(/.{4}/g)?.join('-') || key;
+
+        if (typeof QRious === 'undefined') {
+            alert('QR Code library failed to load.');
+            return;
+        }
+
+        try {
+            new QRious({
+                element: canvas,
+                value: formatted,
+                size: 200,
+                level: 'M'
+            });
+            if (displayEl) displayEl.textContent = formatted;
+            modal?.show();
+        } catch (error) {
+            alert('Failed to generate QR code: ' + error.message);
+        }
+    });
+
+    // Download QR as PNG
+    downloadBtn?.addEventListener('click', function() {
+        if (canvas) {
+            const link = document.createElement('a');
+            link.download = 'stegasoo-channel-key.png';
+            link.href = canvas.toDataURL('image/png');
+            link.click();
+        }
+    });
+
+    // Print tiled QR sheet (US Letter)
+    document.getElementById('channelKeyQrPrint')?.addEventListener('click', function() {
+        if (canvas && displayEl) {
+            printQrSheet(canvas, displayEl.textContent, 'Channel Key');
+        }
+    });
+});
+
+// Print QR codes tiled on US Letter paper (8.5" x 11")
+function printQrSheet(canvas, keyText, title) {
+    const qrDataUrl = canvas.toDataURL('image/png');
+    const printWindow = window.open('', '_blank');
+    if (!printWindow) {
+        alert('Please allow popups to print');
+        return;
+    }
+
+    // US Letter: 8.5" x 11" - create 4x5 grid of QR codes
+    const cols = 4;
+    const rows = 5;
+
+    // Split key into two lines (4 groups each)
+    const keyParts = keyText.split('-');
+    const keyLine1 = keyParts.slice(0, 4).join('-');
+    const keyLine2 = keyParts.slice(4).join('-');
+
+    let qrGrid = '';
+    for (let i = 0; i < rows * cols; i++) {
+        qrGrid += `
+            <div class="qr-tile">
+                <div class="key-text">${keyLine1}</div>
+                <img src="${qrDataUrl}" alt="QR">
+                <div class="key-text">${keyLine2}</div>
+            </div>
+        `;
+    }
+
+    printWindow.document.write(`
+        <!DOCTYPE html>
+        <html>
+        <head>
+            <title></title>
+            <style>
+                @page {
+                    size: letter;
+                    margin: 0.2in;
+                    margin-top: 0.1in;
+                    margin-bottom: 0.1in;
+                }
+                @media print {
+                    @page { margin: 0.15in; }
+                    html, body { margin: 0; padding: 0; }
+                }
+                * { margin: 0; padding: 0; box-sizing: border-box; }
+                body {
+                    font-family: 'Courier New', monospace;
+                    background: white;
+                }
+                .grid {
+                    display: grid;
+                    grid-template-columns: repeat(${cols}, 1fr);
+                    gap: 0;
+                    margin-top: 0.09in;
+                }
+                .qr-tile {
+                    border: 1px dashed #ccc;
+                    padding: 0.04in;
+                    text-align: center;
+                    page-break-inside: avoid;
+                }
+                .qr-tile img {
+                    width: 1.6in;
+                    height: 1.6in;
+                }
+                .key-text {
+                    font-size: 10pt;
+                    font-weight: bold;
+                    color: #333;
+                    line-height: 1.2;
+                }
+                .footer {
+                    display: none;
+                }
+            </style>
+        </head>
+        <body>
+            <div class="grid">${qrGrid}</div>
+            <div class="footer">Cut along dashed lines</div>
+            <script>
+                window.onload = function() { window.print(); };
+            <\/script>
+        </body>
+        </html>
+    `);
+    printWindow.document.close();
+}
+</script>
+{% endblock %}

frontends/web/templates/base.html

@@ -5,44 +5,46 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>{% block title %}Stegasoo{% endblock %}</title>
     <link rel="icon" type="image/svg+xml" href="{{ url_for('static', filename='favicon.svg') }}">
-    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css" rel="stylesheet">
-    <link href="https://cdn.jsdelivr.net/npm/bootstrap-icons@1.11.1/font/bootstrap-icons.css" rel="stylesheet">
+    <link href="{{ url_for('static', filename='vendor/css/bootstrap.min.css') }}" rel="stylesheet">
+    <link href="{{ url_for('static', filename='vendor/css/bootstrap-icons.min.css') }}" rel="stylesheet">
     <link href="{{ url_for('static', filename='style.css') }}" rel="stylesheet">
 </head>
 <body>
     <nav class="navbar navbar-expand-lg navbar-dark">
-        <div class="container">
-            <a class="navbar-brand d-flex align-items-center" href="/">
-                <img src="{{ url_for('static', filename='logo.svg') }}" alt="Stegasoo" height="36" class="me-2">
-                <span style="position: relative; display: inline-block; margin-top: -14px;">
-                    <span class="fw-bold title-gold">Stegasoo</span>
-                    <span class="badge bg-success" style="position: absolute; font-size: 0.45rem; bottom: -8px; right: 6px;">v4.1</span>
-                </span>
+        <div class="container-fluid">
+            <a class="navbar-brand" href="/" style="padding-left: 6px; margin-right: 8px;">
+                <img src="{{ url_for('static', filename='logo.svg') }}" alt="Stegasoo" height="28">
             </a>
+            {% if channel_configured %}
+            <span class="badge bg-success bg-opacity-25 small" style="padding-left: 0.35rem;" title="Private Channel: {{ channel_fingerprint }}">
+                <i class="bi bi-shield-lock me-2" style="color: #6ee7b7;"></i><code style="font-size: 0.7rem; font-weight: 300; color: #c9a860;">{{ channel_fingerprint[:4] }}-••••-{{ channel_fingerprint[-4:] }}</code>
+            </span>
+            {% else %}
+            <span class="badge bg-secondary bg-opacity-25 small text-muted" style="padding-left: 0.35rem;" title="Public Channel: No shared channel key configured. Messages use only passphrase and PIN for encryption.">
+                <i class="bi bi-globe me-1"></i>Public Channel
+            </span>
+            {% endif %}
             <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNav">
                 <span class="navbar-toggler-icon"></span>
             </button>
             <div class="collapse navbar-collapse" id="navbarNav">
-                <ul class="navbar-nav ms-auto">
+                <ul class="navbar-nav ms-auto nav-icons">
                     <li class="nav-item">
-                        <a class="nav-link" href="/"><i class="bi bi-house me-1"></i> Home</a>
+                        <a class="nav-link nav-expand" href="/"><i class="bi bi-house"></i><span>Home</span></a>
                     </li>
                     {% if not auth_enabled or is_authenticated %}
                     <li class="nav-item">
-                        <a class="nav-link" href="/encode"><i class="bi bi-lock me-1"></i> Encode</a>
+                        <a class="nav-link nav-expand" href="/encode"><i class="bi bi-lock"></i><span>Encode</span></a>
                     </li>
                     <li class="nav-item">
-                        <a class="nav-link" href="/decode"><i class="bi bi-unlock me-1"></i> Decode</a>
+                        <a class="nav-link nav-expand" href="/decode"><i class="bi bi-unlock"></i><span>Decode</span></a>
                     </li>
                     <li class="nav-item">
-                        <a class="nav-link" href="/generate"><i class="bi bi-key me-1"></i> Generate</a>
+                        <a class="nav-link nav-expand" href="/generate"><i class="bi bi-key"></i><span>Generate</span></a>
                     </li>
                     {% endif %}
                     <li class="nav-item">
-                        <a class="nav-link" href="/about"><i class="bi bi-info-circle me-1"></i> About</a>
-                    </li>
-                    <li class="nav-item">
-                        <a class="nav-link" href="/tools"><i class="bi bi-tools me-1"></i> Tools</a>
+                        <a class="nav-link nav-expand" href="/tools"><i class="bi bi-tools"></i><span>Tools</span></a>
                     </li>
                     {% if auth_enabled %}
                         {% if is_authenticated %}
@@ -54,6 +56,7 @@
                                 <li><a class="dropdown-item" href="/account"><i class="bi bi-gear me-2"></i>Account</a></li>
                                 {% if is_admin %}
                                 <li><a class="dropdown-item" href="/admin/users"><i class="bi bi-people me-2"></i>Users</a></li>
+                                <li><a class="dropdown-item" href="/admin/settings"><i class="bi bi-sliders me-2"></i>System Settings</a></li>
                                 {% endif %}
                                 <li><hr class="dropdown-divider"></li>
                                 <li><a class="dropdown-item" href="/logout"><i class="bi bi-box-arrow-left me-2"></i>Logout</a></li>
@@ -96,11 +99,15 @@
             <small>
                 <img src="{{ url_for('static', filename='favicon.svg') }}" alt="" height="16" class="me-1" style="vertical-align: text-bottom;">
                 Stegasoo v{{ version }} — Steganography with Reference Photo + Passphrase + PIN/Key
+                <span class="mx-2">|</span>
+                <a href="/about" class="text-muted text-decoration-none"><i class="bi bi-info-circle me-1"></i>About</a>
             </small>
         </div>
     </footer>
 
-    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.min.js"></script>
+    <script src="{{ url_for('static', filename='vendor/js/bootstrap.bundle.min.js') }}"></script>
+    <!-- QR Code scanning library (local) -->
+    <script src="{{ url_for('static', filename='vendor/js/html5-qrcode.min.js') }}"></script>
     <script>
     // Initialize toasts (auto-hide after delay)
     document.querySelectorAll('.toast').forEach(el => new bootstrap.Toast(el));

frontends/web/templates/decode.html

@@ -4,6 +4,79 @@
 
 {% block content %}
 <style>
+/* Accordion styling */
+.step-accordion .accordion-button {
+    background: rgba(35, 45, 55, 0.8);
+    color: #fff;
+    padding: 0.75rem 1rem;
+    border-left: 3px solid rgba(255, 230, 153, 0.3);
+    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
+    transition: all 0.3s ease;
+}
+.step-accordion .accordion-button:hover {
+    background: rgba(45, 55, 65, 0.9);
+    border-left-color: rgba(255, 230, 153, 0.5);
+}
+.step-accordion .accordion-button:not(.collapsed) {
+    background: linear-gradient(90deg, rgba(255, 230, 153, 0.12) 0%, rgba(40, 50, 60, 0.85) 40%, rgba(40, 50, 60, 0.85) 100%);
+    color: #fff;
+    box-shadow: inset 0 1px 0 rgba(255, 230, 153, 0.1);
+    border-left: 3px solid #ffe699;
+}
+.step-accordion .accordion-button::after {
+    filter: invert(1) sepia(1) saturate(2) hue-rotate(5deg) brightness(1.2);
+}
+.step-accordion .accordion-body {
+    background: rgba(30, 40, 50, 0.4);
+    padding: 1rem;
+}
+.step-accordion .accordion-item {
+    border-color: rgba(255,255,255,0.1);
+    background: transparent;
+}
+.step-accordion .accordion-item:first-child .accordion-button {
+    border-radius: 0;
+}
+.step-accordion .accordion-item:last-child .accordion-button.collapsed {
+    border-radius: 0;
+}
+.step-summary {
+    font-size: 0.8rem;
+    color: rgba(255,255,255,0.5);
+    margin-left: auto;
+    padding-right: 1rem;
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    max-width: 50%;
+}
+.step-summary.has-content {
+    color: rgba(99, 179, 237, 0.8);
+}
+.step-title {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+}
+.step-number {
+    background: rgba(246, 173, 85, 0.2);
+    color: #f6ad55;
+    width: 1.5rem;
+    height: 1.5rem;
+    border-radius: 50%;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 0.75rem;
+    font-weight: bold;
+    border: 1px solid rgba(246, 173, 85, 0.3);
+}
+.step-number.complete {
+    background: rgba(72, 187, 120, 0.2);
+    color: #48bb78;
+    border-color: rgba(72, 187, 120, 0.3);
+}
+
 /* Glowing passphrase input */
 .passphrase-input {
     background: rgba(30, 40, 50, 0.8) !important;
@@ -13,20 +86,17 @@
     font-size: 1.1rem;
     letter-spacing: 0.5px;
     padding: 12px 16px;
-    transition: border-color 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
+    transition: border-color 0.3s ease, box-shadow 0.3s ease;
 }
-
 .passphrase-input:focus {
     border-color: rgba(99, 179, 237, 0.8) !important;
-    box-shadow: 0 0 20px rgba(99, 179, 237, 0.4), 0 0 40px rgba(99, 179, 237, 0.2) !important;
-    background: rgba(30, 40, 50, 0.95) !important;
+    box-shadow: 0 0 20px rgba(99, 179, 237, 0.4) !important;
 }
-
 .passphrase-input::placeholder {
     color: rgba(99, 179, 237, 0.4);
 }
 
-/* Glowing PIN input */
+/* PIN input */
 .pin-input-container .form-control {
     background: rgba(30, 40, 50, 0.8) !important;
     border: 2px solid rgba(246, 173, 85, 0.3) !important;
@@ -35,76 +105,13 @@
     font-size: 1.2rem;
     letter-spacing: 3px;
     text-align: center;
-    transition: all 0.3s ease;
 }
-
 .pin-input-container .form-control:focus {
     border-color: rgba(246, 173, 85, 0.8) !important;
-    box-shadow: 0 0 20px rgba(246, 173, 85, 0.4), 0 0 40px rgba(246, 173, 85, 0.2) !important;
-    background: rgba(30, 40, 50, 0.95) !important;
+    box-shadow: 0 0 20px rgba(246, 173, 85, 0.4) !important;
 }
 
-.pin-input-container .form-control::placeholder {
-    color: rgba(246, 173, 85, 0.4);
-    letter-spacing: 1px;
-}
-
-/* QR Crop Animation */
-.qr-crop-container {
-    position: relative;
-    overflow: hidden;
-    border-radius: 8px;
-    background: rgba(0, 0, 0, 0.3);
-}
-
-.qr-crop-container img {
-    display: block;
-    max-height: 180px;
-    max-width: 180px;
-    width: auto;
-    margin: 0 auto;
-    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
-}
-
-.qr-crop-container .qr-original {
-    opacity: 1;
-}
-
-.qr-crop-container .qr-cropped {
-    position: absolute;
-    top: 50%;
-    left: 50%;
-    transform: translate(-50%, -50%) scale(0.3);
-    opacity: 0;
-    max-height: 160px;
-    min-width: 140px;
-    min-height: 140px;
-    object-fit: contain;
-}
-
-.qr-crop-container.scan-complete .qr-original {
-    opacity: 0;
-    transform: scale(1.1);
-    filter: blur(4px);
-}
-
-.qr-crop-container.scan-complete .qr-cropped {
-    opacity: 1;
-    transform: translate(-50%, -50%) scale(1);
-}
-
-.qr-crop-container .crop-badge {
-    position: absolute;
-    bottom: 4px;
-    right: 4px;
-    font-size: 0.65rem;
-    opacity: 0;
-    transition: opacity 0.3s ease 0.4s;
-}
-
-.qr-crop-container.scan-complete .crop-badge {
-    opacity: 1;
-}
+/* QR Crop Animation - uses .qr-scan-container from style.css */
 </style>
 
 <div class="row justify-content-center">
@@ -113,13 +120,13 @@
             <div class="card-header">
                 <h5 class="mb-0"><i class="bi bi-unlock-fill me-2"></i>Decode Secret Message or File</h5>
             </div>
-            <div class="card-body">
+            <div class="card-body {% if not decoded_message and not decoded_file %}p-0{% endif %}">
                 {% if decoded_message %}
                 <!-- Text Message Result -->
                 <div class="alert alert-success">
                     <h6><i class="bi bi-check-circle me-2"></i>Message Decrypted Successfully!</h6>
                 </div>
-               
+
                 <label class="form-label text-muted">Decoded Message: <small class="text-secondary">(click to copy)</small></label>
                 <div class="alert-message p-3 rounded bg-dark border border-secondary mb-3" id="decodedContent" style="white-space: pre-wrap; cursor: pointer; transition: border-color 0.2s;"
                      onclick="navigator.clipboard.writeText(this.innerText).then(() => { this.style.borderColor = '#198754'; this.dataset.origText = this.innerHTML; this.innerHTML = '<i class=\'bi bi-check-circle text-success\'></i> Copied to clipboard!'; setTimeout(() => { this.innerHTML = this.dataset.origText; this.style.borderColor = ''; }, 1500); }).catch(() => alert('Failed to copy'))"
@@ -129,13 +136,13 @@
                 <a href="/decode" class="btn btn-outline-light w-100">
                     <i class="bi bi-arrow-repeat me-2"></i>Decode Another
                 </a>
-                
+
                 {% elif decoded_file %}
                 <!-- File Result -->
                 <div class="alert alert-success">
                     <h6><i class="bi bi-check-circle me-2"></i>File Decrypted Successfully!</h6>
                 </div>
-                
+
                 <div class="text-center mb-4">
                     <i class="bi bi-file-earmark-check text-success" style="font-size: 4rem;"></i>
                     <h5 class="mt-3">{{ filename }}</h5>
@@ -144,345 +151,262 @@
                     <small class="text-muted">Type: {{ mime_type }}</small>
                     {% endif %}
                 </div>
-                
+
                 <a href="{{ url_for('decode_download', file_id=file_id) }}" class="btn btn-primary btn-lg w-100 mb-3">
                     <i class="bi bi-download me-2"></i>Download File
                 </a>
-                
+
                 <div class="alert alert-warning small">
                     <i class="bi bi-clock me-1"></i>
-                    <strong>File expires in 5 minutes.</strong> Download now.
+                    <strong>File expires in 10 minutes.</strong> Download now.
                 </div>
-                
+
                 <a href="/decode" class="btn btn-outline-light w-100">
                     <i class="bi bi-arrow-repeat me-2"></i>Decode Another
                 </a>
-                
+
                 {% else %}
                 <!-- Decode Form -->
                 <form method="POST" enctype="multipart/form-data" id="decodeForm">
-                    <div class="row">
-                        <div class="col-md-6 mb-3">
-                            <label class="form-label">
-                                <i class="bi bi-image me-1"></i> Reference Photo
-                            </label>
-                            <div class="drop-zone scan-container" id="refDropZone">
-                                <input type="file" name="reference_photo" accept="image/*" required>
-                                <div class="drop-zone-label">
-                                    <i class="bi bi-cloud-arrow-up fs-3 d-block mb-2 text-muted"></i>
-                                    <span class="text-muted">Drop image or click to browse</span>
-                                </div>
-                                <img class="drop-zone-preview d-none" id="refPreview">
-                                <!-- Scan overlay elements -->
-                                <div class="scan-overlay">
-                                    <div class="scan-grid"></div>
-                                    <div class="scan-line"></div>
-                                </div>
-                                <!-- Corner brackets (shown after scan) -->
-                                <div class="scan-corners">
-                                    <div class="scan-corner tl"></div>
-                                    <div class="scan-corner tr"></div>
-                                    <div class="scan-corner bl"></div>
-                                    <div class="scan-corner br"></div>
-                                </div>
-                                <!-- Data panel (shown after scan) -->
-                                <div class="scan-data-panel">
-                                    <div class="scan-data-filename">
-                                        <i class="bi bi-check-circle-fill"></i>
-                                        <span id="refFileName">image.jpg</span>
-                                    </div>
-                                    <div class="scan-data-row">
-                                        <span class="scan-status-badge">Hash Acquired</span>
-                                        <span class="scan-data-value" id="refFileSize">--</span>
-                                    </div>
-                                    <div class="scan-hash-preview" id="refHashPreview">SHA256: ················</div>
-                                </div>
-                            </div>
-                            <div class="form-text">
-                                The same reference photo used for encoding
-                            </div>
-                        </div>
-                        
-                        <div class="col-md-6 mb-3">
-                            <label class="form-label">
-                                <i class="bi bi-file-earmark-image me-1"></i> Stego Image
-                            </label>
-                            <div class="drop-zone pixel-container" id="stegoDropZone">
-                                <input type="file" name="stego_image" accept="image/*" required>
-                                <div class="drop-zone-label">
-                                    <i class="bi bi-cloud-arrow-up fs-3 d-block mb-2 text-muted"></i>
-                                    <span class="text-muted">Drop image or click to browse</span>
-                                </div>
-                                <img class="drop-zone-preview d-none" id="stegoPreview">
-                                <!-- Pixel blocks overlay - populated by JS -->
-                                <div class="pixel-blocks"></div>
-                                <!-- Pixel scan line -->
-                                <div class="pixel-scan-line"></div>
-                                <!-- Corner brackets -->
-                                <div class="pixel-corners">
-                                    <div class="pixel-corner tl"></div>
-                                    <div class="pixel-corner tr"></div>
-                                    <div class="pixel-corner bl"></div>
-                                    <div class="pixel-corner br"></div>
-                                </div>
-                                <!-- Data panel -->
-                                <div class="pixel-data-panel">
-                                    <div class="pixel-data-filename">
-                                        <i class="bi bi-check-circle-fill"></i>
-                                        <span id="stegoFileName">image.png</span>
-                                    </div>
-                                    <div class="pixel-data-row">
-                                        <span class="pixel-status-badge">Stego Loaded</span>
-                                        <span class="pixel-data-value" id="stegoFileSize">--</span>
-                                    </div>
-                                    <div class="pixel-dimensions" id="stegoDims">-- × -- px</div>
-                                </div>
-                            </div>
-                            <div class="form-text">
-                                The image containing the hidden message/file
-                            </div>
-                        </div>
-                    </div>
-                    
-                    <div class="mb-3">
-                        <label class="form-label">
-                            <i class="bi bi-chat-quote me-1"></i> Passphrase
-                        </label>
-                        <input type="text" name="passphrase" id="passphraseInput" class="form-control passphrase-input" 
-                               placeholder="e.g., correct horse battery staple" required>
-                        <div class="form-text">
-                            The passphrase used during encoding (typically 4 words)
-                        </div>
-                    </div>
-                    
-                    <hr class="my-4">
-                    
-                    <h6 class="text-muted mb-3">
-                        SECURITY FACTORS 
-                        <span class="text-warning small">(provide same factors used during encoding)</span>
-                    </h6>
-                    
-                    <div class="mb-3">
-                      <div class="security-box">
-                        <label class="form-label">
-                            <i class="bi bi-file-earmark-lock me-1"></i> RSA Key
-                        </label>
 
-                        <!-- RSA Input Method Toggle -->
-                        <div class="btn-group w-100 mb-2" role="group">
-                            <input type="radio" class="btn-check" name="rsa_input_method" id="rsaMethodFile" value="file" checked>
-                            <label class="btn btn-outline-secondary btn-sm" for="rsaMethodFile">
-                                <i class="bi bi-file-earmark me-1"></i>.pem File
-                            </label>
+                    <div class="accordion step-accordion" id="decodeAccordion">
 
-                            <input type="radio" class="btn-check" name="rsa_input_method" id="rsaMethodQr" value="qr">
-                            <label class="btn btn-outline-secondary btn-sm" for="rsaMethodQr">
-                                <i class="bi bi-qr-code me-1"></i>QR Code
-                            </label>
-                        </div>
-
-                        <!-- .pem File Input -->
-                        <div id="rsaFileSection">
-                            <input type="file" name="rsa_key" class="form-control form-control-sm" id="rsaKeyInput" accept=".pem,.key,application/x-pem-file">
-                        </div>
-
-                        <!-- QR Code Input -->
-                        <div id="rsaQrSection" class="d-none">
-                            <div class="drop-zone p-3" id="qrDropZone">
-                                <input type="file" name="rsa_key_qr" accept="image/*" id="rsaKeyQrInput">
-                                <div class="drop-zone-label text-center">
-                                    <i class="bi bi-qr-code-scan fs-4 d-block text-muted mb-1"></i>
-                                    <span class="text-muted small">Drop QR image or click to browse</span>
-                                </div>
-                                <!-- Crop animation container -->
-                                <div class="qr-scan-container qr-crop-container d-none" id="qrCropContainer">
-                                    <img class="qr-original" id="qrOriginal" alt="Original">
-                                    <img class="qr-cropped" id="qrCropped" alt="Cropped QR">
-                                    <!-- Data panel -->
-                                    <div class="qr-data-panel">
-                                        <div class="qr-data-filename">
-                                            <i class="bi bi-check-circle-fill"></i>
-                                            <span>RSA Key loaded</span>
-                                        </div>
-                                        <div class="qr-data-row">
-                                            <span class="qr-status-badge">RSA Key</span>
-                                            <span class="qr-data-value">--</span>
-                                        </div>
-                                    </div>
-                                </div>
-                            </div>
-                        </div>
-
-                        <!-- Key Password (always visible) -->
-                        <div class="input-group input-group-sm mt-2">
-                            <input type="password" name="rsa_password" class="form-control" id="rsaPasswordInput" placeholder="Key password (if encrypted)">
-                            <button class="btn btn-outline-secondary" type="button" data-toggle-password="rsaPasswordInput">
-                                <i class="bi bi-eye"></i>
-                            </button>
-                        </div>
-                      </div>
-                    </div>
-
-                    <!-- PIN + Channel Row -->
-                    <div class="row">
-                        <div class="col-md-6 mb-3">
-                          <div class="security-box h-100">
-                            <label class="form-label"><i class="bi bi-123 me-1"></i> PIN</label>
-                            <div class="input-group pin-input-container">
-                                <input type="password" name="pin" class="form-control" id="pinInput" placeholder="••••••" maxlength="9">
-                                <button class="btn btn-outline-secondary" type="button" data-toggle-password="pinInput">
-                                    <i class="bi bi-eye"></i>
+                        <!-- ================================================================
+                             STEP 1: IMAGES & MODE
+                             ================================================================ -->
+                        <div class="accordion-item">
+                            <h2 class="accordion-header">
+                                <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#stepImages">
+                                    <span class="step-title">
+                                        <span class="step-number" id="stepImagesNumber">1</span>
+                                        <i class="bi bi-images me-1"></i> Images & Mode
+                                    </span>
+                                    <span class="step-summary" id="stepImagesSummary">Select reference & stego</span>
                                 </button>
-                            </div>
-                            <div class="form-text">If PIN was used during encoding</div>
-                          </div>
-                        </div>
+                            </h2>
+                            <div id="stepImages" class="accordion-collapse collapse show" data-bs-parent="#decodeAccordion">
+                                <div class="accordion-body">
 
-                        <div class="col-md-6 mb-3">
-                          <div class="security-box h-100">
-                            <label class="form-label">
-                                <i class="bi bi-broadcast me-1"></i> Channel
-                                <span class="badge bg-info ms-1">v4.1</span>
-                                <a href="/about#channel-keys" class="text-muted ms-1" title="Learn about channels"><i class="bi bi-info-circle"></i></a>
-                            </label>
+                                    <div class="row">
+                                        <div class="col-md-6 mb-3">
+                                            <label class="form-label">
+                                                <i class="bi bi-image me-1"></i> Reference Photo
+                                            </label>
+                                            <div class="drop-zone scan-container" id="refDropZone">
+                                                <input type="file" name="reference_photo" accept="image/*" required id="refPhotoInput">
+                                                <div class="drop-zone-label">
+                                                    <i class="bi bi-cloud-arrow-up fs-3 d-block mb-2 text-muted"></i>
+                                                    <span class="text-muted">Drop image or click</span>
+                                                </div>
+                                                <img class="drop-zone-preview d-none" id="refPreview">
+                                                <div class="scan-overlay"><div class="scan-grid"></div><div class="scan-line"></div></div>
+                                                <div class="scan-corners">
+                                                    <div class="scan-corner tl"></div><div class="scan-corner tr"></div>
+                                                    <div class="scan-corner bl"></div><div class="scan-corner br"></div>
+                                                </div>
+                                                <div class="scan-data-panel">
+                                                    <div class="scan-data-filename"><i class="bi bi-check-circle-fill"></i><span id="refFileName">image.jpg</span></div>
+                                                    <div class="scan-data-row"><span class="scan-status-badge">Hash Acquired</span><span class="scan-data-value" id="refFileSize">--</span></div>
+                                                </div>
+                                            </div>
+                                            <div class="form-text">Same reference photo used for encoding</div>
+                                        </div>
 
-                            <select class="form-select" name="channel_key" id="channelSelectDec">
-                                <option value="auto" selected>Auto{% if channel_configured %} (Server Key){% endif %}</option>
-                                <option value="none">Public</option>
-                                {% if saved_channel_keys %}
-                                <optgroup label="Saved Keys">
-                                    {% for key in saved_channel_keys %}
-                                    <option value="{{ key.channel_key }}" data-key-id="{{ key.id }}">{{ key.name }} ({{ key.channel_key[:4] }}...)</option>
-                                    {% endfor %}
-                                </optgroup>
-                                {% endif %}
-                                <option value="custom">Custom...</option>
-                            </select>
-
-                            <!-- Server channel indicator (compact) -->
-                            <div class="small text-success mt-2 {% if not channel_configured %}d-none{% endif %}" id="channelServerInfoDec" data-fingerprint="{{ (channel_fingerprint[:4] if channel_fingerprint else '') }}-••••-···-••••-{{ channel_fingerprint[-4:] if channel_fingerprint else '' }}">
-                                {% if channel_configured and channel_fingerprint %}
-                                <i class="bi bi-shield-lock me-1"></i>
-                                Server: <code>{{ channel_fingerprint[:4] }}-••••-···-••••-{{ channel_fingerprint[-4:] }}</code>
-                                {% endif %}
-                            </div>
-                          </div>
-                        </div>
-                    </div>
-
-                    <!-- Custom Channel Key Input (shown when Custom selected) -->
-                    <div class="mb-4 d-none" id="channelCustomInputDec">
-                        <div class="security-box">
-                            <label class="form-label"><i class="bi bi-key me-1"></i> Custom Channel Key</label>
-                            <div class="input-group">
-                                <input type="text" name="channel_key_custom" class="form-control font-monospace"
-                                       placeholder="XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX"
-                                       pattern="[A-Za-z0-9]{4}(-[A-Za-z0-9]{4}){7}"
-                                       id="channelKeyInputDec">
-                            </div>
-                        </div>
-                    </div>
-                    
-                    <!-- ================================================================
-                         ADVANCED OPTIONS (v3.0) - Extraction Mode
-                         ================================================================ -->
-                    <div class="mb-4">
-                        <a class="btn btn-sm btn-outline-secondary w-100" data-bs-toggle="collapse" href="#advancedOptionsDec" role="button" aria-expanded="false">
-                            <i class="bi bi-gear me-1"></i> Advanced Options
-                            <i class="bi bi-chevron-down ms-1" id="advancedChevronDec"></i>
-                        </a>
-                        
-                        <div class="collapse" id="advancedOptionsDec">
-                            <div class="card card-body mt-2 bg-dark border-secondary">
-                                
-                                <!-- Extraction Mode Selection -->
-                                <div class="mb-0">
-                                    <label class="form-label">
-                                        <i class="bi bi-cpu me-1"></i> Extraction Mode
-                                        <span class="badge bg-info ms-1">v3.0</span>
-                                    </label>
-                                    
-                                    <div class="d-flex gap-2">
-                                        <!-- Auto Mode -->
-                                        <label class="mode-btn flex-fill active" id="autoModeCard" for="modeAuto">
-                                            <input class="form-check-input" type="radio" name="embed_mode" id="modeAuto" value="auto" checked>
-                                            <i class="bi bi-magic text-success"></i>
-                                            <span class="ms-2"><strong>Auto</strong> <span class="text-muted d-none d-sm-inline">· Try both</span></span>
-                                        </label>
-                                        
-                                        <!-- LSB Mode -->
-                                        <label class="mode-btn flex-fill" id="lsbModeCardDec" for="modeLsbDec">
-                                            <input class="form-check-input" type="radio" name="embed_mode" id="modeLsbDec" value="lsb">
-                                            <i class="bi bi-grid-3x3-gap text-primary"></i>
-                                            <span class="ms-2"><strong>LSB</strong> <span class="text-muted d-none d-sm-inline">· Spatial</span></span>
-                                        </label>
-                                        
-                                        <!-- DCT Mode -->
-                                        <label class="mode-btn flex-fill {% if not has_dct %}opacity-50{% endif %}" id="dctModeCardDec" for="modeDctDec">
-                                            <input class="form-check-input" type="radio" name="embed_mode" id="modeDctDec" value="dct" {% if not has_dct %}disabled{% endif %}>
-                                            <i class="bi bi-soundwave text-warning"></i>
-                                            <span class="ms-2"><strong>DCT</strong> <span class="text-muted d-none d-sm-inline">· Frequency</span></span>
-                                        </label>
+                                        <div class="col-md-6 mb-3">
+                                            <label class="form-label">
+                                                <i class="bi bi-file-earmark-image me-1"></i> Stego Image
+                                            </label>
+                                            <div class="drop-zone pixel-container" id="stegoDropZone">
+                                                <input type="file" name="stego_image" accept="image/*" required id="stegoInput">
+                                                <div class="drop-zone-label">
+                                                    <i class="bi bi-cloud-arrow-up fs-3 d-block mb-2 text-muted"></i>
+                                                    <span class="text-muted">Drop image or click</span>
+                                                </div>
+                                                <img class="drop-zone-preview d-none" id="stegoPreview">
+                                                <div class="pixel-blocks"></div>
+                                                <div class="pixel-scan-line"></div>
+                                                <div class="pixel-corners">
+                                                    <div class="pixel-corner tl"></div><div class="pixel-corner tr"></div>
+                                                    <div class="pixel-corner bl"></div><div class="pixel-corner br"></div>
+                                                </div>
+                                                <div class="pixel-data-panel">
+                                                    <div class="pixel-data-filename"><i class="bi bi-check-circle-fill"></i><span id="stegoFileName">image.png</span></div>
+                                                    <div class="pixel-data-row"><span class="pixel-status-badge">Stego Loaded</span><span class="pixel-data-value" id="stegoFileSize">--</span></div>
+                                                    <div class="pixel-dimensions" id="stegoDims">-- x -- px</div>
+                                                </div>
+                                            </div>
+                                            <div class="form-text">Image containing the hidden message</div>
+                                        </div>
                                     </div>
-                                    
-                                    <div class="form-text mt-2">
-                                        <i class="bi bi-lightbulb me-1"></i>
-                                        <strong>Auto</strong> tries LSB first, then DCT.
-                                        {% if not has_dct %}
-                                        <span class="text-warning ms-2"><i class="bi bi-exclamation-triangle me-1"></i>DCT requires scipy</span>
-                                        {% endif %}
+
+                                    <!-- Extraction Mode -->
+                                    <div class="d-flex gap-2 align-items-center flex-wrap mb-2">
+                                        <div class="btn-group" role="group">
+                                            <input type="radio" class="btn-check" name="embed_mode" id="modeAuto" value="auto" checked>
+                                            <label class="btn btn-outline-secondary text-nowrap" for="modeAuto"><i class="bi bi-magic me-1"></i>Auto</label>
+                                            <input type="radio" class="btn-check" name="embed_mode" id="modeLsb" value="lsb">
+                                            <label class="btn btn-outline-secondary text-nowrap" for="modeLsb"><i class="bi bi-grid-3x3-gap me-1"></i>LSB</label>
+                                            <input type="radio" class="btn-check" name="embed_mode" id="modeDct" value="dct" {% if not has_dct %}disabled{% endif %}>
+                                            <label class="btn btn-outline-secondary text-nowrap" for="modeDct" id="dctModeLabel"><i class="bi bi-soundwave me-1"></i>DCT</label>
+                                        </div>
                                     </div>
+                                    <div class="form-text" id="modeHint">
+                                        <i class="bi bi-lightning me-1"></i>Tries LSB first, then DCT
+                                    </div>
+
                                 </div>
-                                
                             </div>
                         </div>
+
+                        <!-- ================================================================
+                             STEP 2: SECURITY
+                             ================================================================ -->
+                        <div class="accordion-item">
+                            <h2 class="accordion-header">
+                                <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#stepSecurity">
+                                    <span class="step-title">
+                                        <span class="step-number" id="stepSecurityNumber">2</span>
+                                        <i class="bi bi-shield-lock me-1"></i> Security
+                                    </span>
+                                    <span class="step-summary" id="stepSecuritySummary">Passphrase & keys</span>
+                                </button>
+                            </h2>
+                            <div id="stepSecurity" class="accordion-collapse collapse" data-bs-parent="#decodeAccordion">
+                                <div class="accordion-body">
+
+                                    <!-- Passphrase -->
+                                    <div class="mb-3">
+                                        <label class="form-label"><i class="bi bi-chat-quote me-1"></i> Passphrase</label>
+                                        <input type="text" name="passphrase" class="form-control passphrase-input"
+                                               placeholder="e.g., apple forest thunder mountain" required id="passphraseInput">
+                                        <div class="form-text">The passphrase used during encoding</div>
+                                    </div>
+
+                                    <hr class="my-3 opacity-25">
+                                    <div class="small text-muted mb-2">Provide same factors used during encoding</div>
+
+                                    <div class="row">
+                                        <!-- PIN -->
+                                        <div class="col-md-6 mb-2">
+                                            <div class="security-box h-100">
+                                                <label class="form-label"><i class="bi bi-123 me-1"></i> PIN</label>
+                                                <div class="input-group pin-input-container">
+                                                    <input type="password" name="pin" class="form-control" id="pinInput" placeholder="••••••" maxlength="9">
+                                                    <button class="btn btn-outline-secondary" type="button" data-toggle-password="pinInput">
+                                                        <i class="bi bi-eye"></i>
+                                                    </button>
+                                                </div>
+                                                </div>
+                                        </div>
+
+                                        <!-- Channel -->
+                                        <div class="col-md-6 mb-2">
+                                            <div class="security-box h-100">
+                                                <label class="form-label"><i class="bi bi-broadcast me-1"></i> Channel</label>
+                                                <select class="form-select form-select-sm" name="channel_key" id="channelSelectDec">
+                                                    <option value="auto" selected>Auto{% if channel_configured %} (Server){% endif %}</option>
+                                                    <option value="none">Public</option>
+                                                    {% if saved_channel_keys %}
+                                                    <optgroup label="Saved Keys">
+                                                        {% for key in saved_channel_keys %}
+                                                        <option value="{{ key.channel_key }}">{{ key.name }}</option>
+                                                        {% endfor %}
+                                                    </optgroup>
+                                                    {% endif %}
+                                                    <option value="custom">Custom...</option>
+                                                </select>
+                                            </div>
+                                        </div>
+                                    </div>
+
+                                    <!-- Custom Channel Key -->
+                                    <div class="mb-3 d-none" id="channelCustomInputDec">
+                                        <div class="security-box">
+                                            <label class="form-label"><i class="bi bi-key me-1"></i> Custom Channel Key</label>
+                                            <div class="input-group">
+                                                <input type="text" name="channel_key_custom" class="form-control form-control-sm font-monospace"
+                                                       placeholder="XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX" id="channelKeyInputDec">
+                                                <button class="btn btn-outline-secondary btn-sm" type="button" id="channelKeyScanDec" title="Scan QR"><i class="bi bi-camera"></i></button>
+                                            </div>
+                                        </div>
+                                    </div>
+
+                                    <!-- RSA Key -->
+                                    <div class="mb-3">
+                                        <div class="security-box">
+                                            <label class="form-label"><i class="bi bi-file-earmark-lock me-1"></i> RSA Key <span class="text-muted">(if used)</span></label>
+                                            <div class="btn-group w-100 mb-2" role="group">
+                                                <input type="radio" class="btn-check" name="rsa_input_method" id="rsaMethodFile" value="file" checked>
+                                                <label class="btn btn-outline-secondary btn-sm" for="rsaMethodFile"><i class="bi bi-file-earmark me-1"></i>.pem</label>
+                                                <input type="radio" class="btn-check" name="rsa_input_method" id="rsaMethodQr" value="qr">
+                                                <label class="btn btn-outline-secondary btn-sm" for="rsaMethodQr"><i class="bi bi-qr-code me-1"></i>QR</label>
+                                            </div>
+                                            <div id="rsaFileSection">
+                                                <input type="file" name="rsa_key" class="form-control form-control-sm" accept=".pem">
+                                            </div>
+                                            <div id="rsaQrSection" class="d-none d-flex flex-column">
+                                                <input type="hidden" name="rsa_key_pem" id="rsaKeyPem">
+                                                <div class="drop-zone p-2 w-100" id="qrDropZone">
+                                                    <input type="file" name="rsa_key_qr" accept="image/*" id="rsaQrInput">
+                                                    <div class="drop-zone-label text-center">
+                                                        <i class="bi bi-qr-code-scan fs-5 d-block text-muted mb-1"></i>
+                                                        <span class="text-muted small">Drop QR image</span>
+                                                    </div>
+                                                    <div class="qr-scan-container d-none" id="qrCropContainer">
+                                                        <img class="qr-original" id="qrOriginal" alt="Original">
+                                                        <img class="qr-cropped" id="qrCropped" alt="Cropped">
+                                                    </div>
+                                                </div>
+                                                <button type="button" class="btn btn-outline-secondary btn-sm w-100 mt-2" id="rsaQrWebcam">
+                                                    <i class="bi bi-camera me-1"></i>Scan with Camera
+                                                </button>
+                                            </div>
+                                            <div class="input-group input-group-sm mt-2">
+                                                <input type="password" name="rsa_password" class="form-control" id="rsaPasswordInput" placeholder="Key password (if encrypted)">
+                                                <button class="btn btn-outline-secondary" type="button" data-toggle-password="rsaPasswordInput"><i class="bi bi-eye"></i></button>
+                                            </div>
+                                        </div>
+                                    </div>
+
+                                </div>
+                            </div>
+                        </div>
+
                     </div>
-                    
-                    <button type="submit" class="btn btn-primary btn-lg w-100" id="decodeBtn">
-                        <i class="bi bi-unlock me-2"></i>Decode
-                    </button>
+
+                    <!-- Submit Button -->
+                    <div class="p-3">
+                        <button type="submit" class="btn btn-primary btn-lg w-100" id="decodeBtn">
+                            <i class="bi bi-unlock me-2"></i>Decode
+                        </button>
+                    </div>
+
                 </form>
-                
                 {% endif %}
             </div>
         </div>
-        
+
         {% if not decoded_message and not decoded_file %}
+        <!-- Troubleshooting Card -->
         <div class="card mt-4">
             <div class="card-body">
                 <h6 class="text-muted mb-3"><i class="bi bi-question-circle me-2"></i>Troubleshooting</h6>
                 <ul class="list-unstyled text-muted small mb-0">
                     <li class="mb-2">
                         <i class="bi bi-check-circle-fill text-success me-1"></i>
-                        Use the <strong>exact same reference photo</strong> file (byte-for-byte identical)
+                        Use the <strong>exact same reference photo</strong> (byte-for-byte identical)
                     </li>
                     <li class="mb-2">
                         <i class="bi bi-check-circle-fill text-success me-1"></i>
-                        Enter the <strong>exact passphrase</strong> used during encoding (case-sensitive, spacing matters)
-                    </li>
-                    <li class="mb-2">
-                        <i class="bi bi-check-circle-fill text-success me-1"></i>
-                        Provide the <strong>same security factors</strong> (PIN and/or RSA key) used during encoding
+                        Enter the <strong>exact passphrase</strong> used during encoding
                     </li>
                     <li class="mb-2">
                         <i class="bi bi-exclamation-triangle-fill text-warning me-1"></i>
-                        Ensure the stego image hasn't been <strong>resized, cropped, or recompressed</strong>
-                    </li>
-                    <li class="mb-2">
-                        <i class="bi bi-exclamation-triangle-fill text-warning me-1"></i>
-                        <strong>Format compatibility:</strong> v4.0 cannot decode messages from v3.1 or earlier (different format)
-                    </li>
-                    <li class="mb-2">
-                        <i class="bi bi-broadcast text-info me-1"></i>
-                        <strong>Channel key:</strong> Use the same channel (Auto/Public/Custom) that was used during encoding
-                    </li>
-                    <li class="mb-2">
-                        <i class="bi bi-info-circle-fill text-info me-1"></i>
-                        If using an RSA key, verify the <strong>password is correct</strong> (if key is encrypted)
+                        Ensure the stego image hasn't been <strong>resized or recompressed</strong>
                     </li>
                     <li class="mb-0">
                         <i class="bi bi-info-circle-fill text-info me-1"></i>
-                        If auto-detection fails, try specifying <strong>LSB or DCT mode</strong> in Advanced Options
+                        If auto-detection fails, try specifying <strong>LSB or DCT mode</strong>
                     </li>
                 </ul>
             </div>
@@ -495,31 +419,106 @@
 {% block scripts %}
 <script src="{{ url_for('static', filename='js/stegasoo.js') }}"></script>
 <script>
-// Extraction mode button active state toggle
-const extractModeRadios = document.querySelectorAll('input[name="embed_mode"]');
-const extractModeBtns = { 
-    'auto': document.getElementById('autoModeCard'), 
-    'lsb': document.getElementById('lsbModeCardDec'), 
-    'dct': document.getElementById('dctModeCardDec') 
+// ============================================================================
+// MODE HINT - Dynamic text based on selected extraction mode
+// ============================================================================
+const modeHints = {
+    auto: { icon: 'lightning', text: 'Tries LSB first, then DCT' },
+    lsb: { icon: 'hdd', text: 'For email and direct transfers' },
+    dct: { icon: 'phone', text: 'For social media images' }
 };
 
-extractModeRadios.forEach(radio => {
-    radio.addEventListener('change', () => {
-        Object.values(extractModeBtns).forEach(btn => btn?.classList.remove('active'));
-        extractModeBtns[radio.value]?.classList.add('active');
+document.querySelectorAll('input[name="embed_mode"]').forEach(radio => {
+    radio.addEventListener('change', function() {
+        const hint = document.getElementById('modeHint');
+        const data = modeHints[this.value];
+        if (hint && data) {
+            hint.innerHTML = `<i class="bi bi-${data.icon} me-1"></i>${data.text}`;
+        }
     });
 });
 
-// Advanced options chevron
-const advancedOptionsDec = document.getElementById('advancedOptionsDec');
-advancedOptionsDec?.addEventListener('show.bs.collapse', () => {
-    document.getElementById('advancedChevronDec')?.classList.replace('bi-chevron-down', 'bi-chevron-up');
-});
-advancedOptionsDec?.addEventListener('hide.bs.collapse', () => {
-    document.getElementById('advancedChevronDec')?.classList.replace('bi-chevron-up', 'bi-chevron-down');
-});
+// ============================================================================
+// ACCORDION SUMMARY UPDATES
+// ============================================================================
+
+function updateImagesSummary() {
+    const ref = document.getElementById('refPhotoInput')?.files[0];
+    const stego = document.getElementById('stegoInput')?.files[0];
+    const mode = document.querySelector('input[name="embed_mode"]:checked')?.value?.toUpperCase() || 'AUTO';
+    const summary = document.getElementById('stepImagesSummary');
+    const stepNum = document.getElementById('stepImagesNumber');
+
+    if (ref && stego) {
+        const refName = ref.name.length > 12 ? ref.name.slice(0, 10) + '..' : ref.name;
+        const stegoName = stego.name.length > 12 ? stego.name.slice(0, 10) + '..' : stego.name;
+        summary.textContent = `${refName} + ${stegoName}, ${mode}`;
+        summary.classList.add('has-content');
+        stepNum.classList.add('complete');
+        stepNum.innerHTML = '<i class="bi bi-check"></i>';
+    } else if (ref || stego) {
+        summary.textContent = ref ? ref.name.slice(0, 15) : stego.name.slice(0, 15);
+        summary.classList.remove('has-content');
+        stepNum.classList.remove('complete');
+        stepNum.textContent = '1';
+    } else {
+        summary.textContent = 'Select reference & stego';
+        summary.classList.remove('has-content');
+        stepNum.classList.remove('complete');
+        stepNum.textContent = '1';
+    }
+}
+
+function updateSecuritySummary() {
+    const passphrase = document.getElementById('passphraseInput')?.value || '';
+    const pin = document.getElementById('pinInput')?.value || '';
+    const rsaFile = document.querySelector('input[name="rsa_key"]')?.files[0];
+    const rsaPem = document.getElementById('rsaKeyPem')?.value || '';
+    const summary = document.getElementById('stepSecuritySummary');
+    const stepNum = document.getElementById('stepSecurityNumber');
+
+    const parts = [];
+    if (passphrase.trim()) parts.push('passphrase');
+    if (pin) parts.push('PIN');
+    if (rsaFile || rsaPem) parts.push('RSA');
+
+    if (parts.length > 0) {
+        summary.textContent = parts.join(' + ');
+        summary.classList.add('has-content');
+        if (passphrase.trim()) {
+            stepNum.classList.add('complete');
+            stepNum.innerHTML = '<i class="bi bi-check"></i>';
+        }
+    } else {
+        summary.textContent = 'Passphrase & keys';
+        summary.classList.remove('has-content');
+        stepNum.classList.remove('complete');
+        stepNum.textContent = '2';
+    }
+}
+
+// Attach listeners
+document.getElementById('refPhotoInput')?.addEventListener('change', updateImagesSummary);
+document.getElementById('stegoInput')?.addEventListener('change', updateImagesSummary);
+document.querySelectorAll('input[name="embed_mode"]').forEach(r => r.addEventListener('change', updateImagesSummary));
+
+document.getElementById('passphraseInput')?.addEventListener('input', updateSecuritySummary);
+document.getElementById('pinInput')?.addEventListener('input', updateSecuritySummary);
+document.querySelector('input[name="rsa_key"]')?.addEventListener('change', updateSecuritySummary);
+
+// ============================================================================
+// MODE SWITCHING
+// ============================================================================
+
+// Apply disabled styling to DCT if not available
+if (document.getElementById('modeDct')?.disabled) {
+    document.getElementById('dctModeLabel')?.classList.add('disabled', 'text-muted');
+}
+
+// ============================================================================
+// LOADING STATE
+// ============================================================================
 
-// Loading state for decode button
 Stegasoo.initFormLoading('decodeForm', 'decodeBtn', 'Decoding...');
 </script>
 {% endblock %}

frontends/web/templates/encode_result.html

@@ -128,7 +128,7 @@
                     <i class="bi bi-exclamation-triangle me-1"></i>
                     <strong>Important:</strong>
                     <ul class="mb-0 mt-2">
-                        <li>This file expires in <strong>5 minutes</strong></li>
+                        <li>This file expires in <strong>10 minutes</strong></li>
                         <li>Do <strong>not</strong> resize or recompress the image</li>
                         {% if embed_mode == 'dct' and output_format == 'jpeg' %}
                         <li>JPEG format is lossy - avoid re-saving or editing</li>

frontends/web/templates/generate.html

@@ -65,11 +65,7 @@
                                 <select name="rsa_bits" class="form-select form-select-sm" id="rsaBitsSelect">
                                     <option value="2048" selected>2048 bits (~128 bits entropy)</option>
                                     <option value="3072">3072 bits (~128 bits entropy)</option>
-                                    <option value="4096">4096 bits (~128 bits entropy)</option>
                                 </select>
-                                <div class="form-text text-warning d-none" id="rsaQrWarning">
-                                    <i class="bi bi-exclamation-triangle me-1"></i>QR code unavailable for keys &gt;3072 bits
-                                </div>
                             </div>
                         </div>
                     </div>
@@ -100,8 +96,8 @@
                                     <span class="input-group-text"><i class="bi bi-key"></i></span>
                                     <input type="text" class="form-control font-monospace" id="channelKeyGenerated"
                                            placeholder="Click Generate to create a key" readonly>
-                                    <button class="btn btn-outline-primary" type="button" id="generateChannelKeyBtn">
-                                        <i class="bi bi-shuffle me-1"></i>Generate
+                                    <button class="btn btn-outline-primary" type="button" id="generateChannelKeyBtn" title="Generate Channel Key">
+                                        <i class="bi bi-shuffle"></i>
                                     </button>
                                     <button class="btn btn-outline-secondary" type="button" id="copyChannelKeyBtn" disabled title="Copy to clipboard">
                                         <i class="bi bi-clipboard"></i>
@@ -286,12 +282,6 @@
                                     <i class="bi bi-shield-exclamation me-1"></i>
                                     <strong>Security note:</strong> The QR code contains your unencrypted private key.
                                     Only scan in a secure environment. Consider using the password-protected download instead.
-                                    {% if rsa_bits >= 4096 %}
-                                    <br><br>
-                                    <i class="bi bi-exclamation-triangle me-1"></i>
-                                    <strong>4096-bit keys</strong> produce very dense QR codes. If scanning fails, 
-                                    use the PEM text or download options instead.
-                                    {% endif %}
                                 </div>
                             </div>
                         </div>
@@ -483,17 +473,17 @@
 /* Responsive */
 @media (max-width: 576px) {
     .pin-container, .passphrase-container {
-        padding: 1rem 1.25rem;
+        padding: 1rem 0.75rem;
     }
-    
+
     .pin-digit-box {
-        width: 2.25rem;
-        height: 2.75rem;
-        font-size: 1.25rem;
+        width: 1.9rem;
+        height: 2.4rem;
+        font-size: 1.15rem;
     }
-    
+
     .pin-digits-row {
-        gap: 0.35rem;
+        gap: 0.25rem;
     }
     
     .passphrase-text {

frontends/web/templates/index.html

@@ -3,170 +3,64 @@
 {% block title %}Stegasoo - Secure Steganography{% endblock %}
 
 {% block content %}
+<style>
+.home-icon {
+    display: inline-flex;
+    flex-direction: column;
+    align-items: center;
+    padding: 1rem 1.5rem;
+    text-decoration: none;
+    transition: all 0.15s ease;
+}
+.home-icon i {
+    font-size: 2.5rem;
+    color: #fff;
+    margin-bottom: 0.5rem;
+    filter: drop-shadow(0 3px 2px rgba(0, 0, 0, 0.9));
+    transition: all 0.15s ease;
+}
+.home-icon span {
+    font-size: 0.7rem;
+    font-weight: 500;
+    text-transform: uppercase;
+    letter-spacing: 1px;
+    color: rgba(255, 255, 255, 0.5);
+    opacity: 0;
+    transform: translateY(-8px);
+    transition: all 0.15s ease;
+}
+.home-icon:hover i {
+    color: #e5d058;
+    transform: translateY(-3px);
+    filter: drop-shadow(0 5px 4px rgba(0, 0, 0, 0.8));
+}
+.home-icon:hover span {
+    opacity: 1;
+    transform: translateY(0);
+    color: #e5d058;
+}
+</style>
 
-<div class="row mb-4">
-    <div class="col-12">
-        <div class="d-flex align-items-end justify-content-center gap-4">
-            <img src="{{ url_for('static', filename='logo.svg') }}" alt="Stegasoo" height="155">
-            <div style="margin-bottom: 40px;">
-                <h1 class="display-4 fw-bold mb-2 title-gold">
-                    Stegasoo
-                    <span class="badge bg-success fs-6 ms-2">v4.1</span>
-                </h1>
-                <p class="lead text-muted mb-0">Hide encrypted data in plain sight.</p>
-            </div>
+<div class="d-flex flex-column align-items-center justify-content-center" style="min-height: 70vh;">
+
+    <!-- Hero -->
+    <div class="d-flex align-items-center mb-4" style="gap: 8px;">
+        <div class="position-relative">
+            <img src="{{ url_for('static', filename='logo.svg') }}" alt="Stegasoo" height="80">
+            <span class="badge bg-success position-absolute" style="bottom: 1px; left: -6px; font-size: 0.6rem;">v4.1</span>
         </div>
-    </div>
-</div>
-
-<!-- Channel Status Banner (v4.0.0) -->
-{% if channel_configured %}
-<div class="alert alert-success mb-4">
-    <div class="d-flex align-items-center justify-content-between">
         <div>
-            <i class="bi bi-shield-lock me-2"></i>
-            <strong>Private Channel Mode</strong>
-        </div>
-        <div class="key-capsule">
-            <span class="badge led-badge-yellow"><span class="led-indicator led-yellow me-1"></span>Key Loaded</span>
-            <code class="small ms-2">{{ channel_fingerprint }}</code>
+            <h1 class="display-5 fw-bold title-gold mb-0">Stegasoo</h1>
+            <p class="text-muted mb-0 small" style="margin-top: 3px; padding-left: 3px; font-size: 0.85rem; text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);">Hide encrypted data in plain sight.</p>
         </div>
     </div>
-</div>
-{% endif %}
 
-<div class="row g-4 mb-5">
-    <!-- Encode Card -->
-    <div class="col-md-4">
-        <a href="/encode" class="text-decoration-none card-link">
-            <div class="card h-100 feature-card">
-                <div class="card-header text-center py-3">
-                    <i class="bi bi-lock-fill fs-1 embossed-icon"></i>
-                </div>
-                <div class="card-body text-center">
-                    <h5 class="card-title">Encode</h5>
-                    <p class="card-text text-muted">
-                        Hide encrypted messages or files inside images
-                    </p>
-                </div>
-            </div>
-        </a>
+    <!-- Action Icons -->
+    <div class="d-flex gap-4">
+        <a href="/encode" class="home-icon"><i class="bi bi-lock-fill"></i><span>Encode</span></a>
+        <a href="/decode" class="home-icon"><i class="bi bi-unlock-fill"></i><span>Decode</span></a>
+        <a href="/generate" class="home-icon"><i class="bi bi-key-fill"></i><span>Generate</span></a>
     </div>
 
-    <!-- Decode Card -->
-    <div class="col-md-4">
-        <a href="/decode" class="text-decoration-none card-link">
-            <div class="card h-100 feature-card">
-                <div class="card-header text-center py-3">
-                    <i class="bi bi-unlock-fill fs-1 embossed-icon"></i>
-                </div>
-                <div class="card-body text-center">
-                    <h5 class="card-title">Decode</h5>
-                    <p class="card-text text-muted">
-                        Extract and decrypt hidden data from stego images
-                    </p>
-                </div>
-            </div>
-        </a>
-    </div>
- 
-    <!-- Generate Card -->
-    <div class="col-md-4">
-        <a href="/generate" class="text-decoration-none card-link">
-            <div class="card h-100 feature-card">
-                <div class="card-header text-center py-3">
-                    <i class="bi bi-key-fill fs-1 embossed-icon"></i>
-                </div>
-                <div class="card-body text-center">
-                    <h5 class="card-title">Generate</h5>
-                    <p class="card-text text-muted">
-                        Create passphrases, PINs, and RSA keys
-                    </p>
-                </div>
-            </div>
-        </a>
-    </div>
-</div>
-
-<!-- Embedding Modes -->
-<div class="card mb-4">
-    <div class="card-header">
-        <h5 class="mb-0"><i class="bi bi-cpu me-2"></i>Embedding Modes</h5>
-    </div>
-    <div class="card-body">
-        <div class="row text-center">
-            <div class="col-md-6 mb-3 mb-md-0">
-                <div class="p-3 bg-dark rounded h-100">
-                    <i class="bi bi-soundwave text-warning fs-2 d-block mb-2"></i>
-                    <strong>DCT Mode</strong>
-                    <span class="badge bg-success ms-1">Default</span>
-                    <div class="small text-muted mt-2">
-                        Survives JPEG recompression<br>
-                        Best for social media
-                    </div>
-                </div>
-            </div>
-            <div class="col-md-6">
-                <div class="p-3 bg-dark rounded h-100">
-                    <i class="bi bi-grid-3x3-gap text-primary fs-2 d-block mb-2"></i>
-                    <strong>LSB Mode</strong>
-                    <div class="small text-muted mt-2">
-                        Higher capacity (~375 KB/MP)<br>
-                        Best for email &amp; file transfer
-                    </div>
-                </div>
-            </div>
-        </div>
-    </div>
-</div>
-
-<div class="card">
-    <div class="card-header d-flex justify-content-between align-items-center">
-        <h5 class="mb-0"><i class="bi bi-diagram-3 me-2"></i>How It Works</h5>
-        <a href="/about" class="btn btn-sm btn-outline-light">Learn More</a>
-    </div>
-    <div class="card-body">
-        <div class="row">
-            <div class="col-md-6">
-                <h6 class="text-primary"><i class="bi bi-key me-2"></i>You Provide</h6>
-                <ul class="list-unstyled small">
-                    <li class="mb-1">
-                        <i class="bi bi-image text-info me-2"></i>
-                        <strong>Reference Photo</strong>: shared secret
-                    </li>
-                    <li class="mb-1">
-                        <i class="bi bi-chat-quote text-info me-2"></i>
-                        <strong>Passphrase</strong>: 4+ words
-                    </li>
-                    <li class="mb-1">
-                        <i class="bi bi-123 text-info me-2"></i>
-                        <strong>PIN</strong>: 6-9 digits (or RSA key)
-                    </li>
-                </ul>
-            </div>
-            <div class="col-md-6">
-                <h6 class="text-primary"><i class="bi bi-shield-check me-2"></i>Security</h6>
-                <ul class="list-unstyled small">
-                    <li class="mb-1">
-                        <i class="bi bi-lock text-success me-2"></i>
-                        AES-256-GCM encryption
-                    </li>
-                    <li class="mb-1">
-                        <i class="bi bi-memory text-success me-2"></i>
-                        Argon2id key derivation (256MB)
-                    </li>
-                    <li class="mb-1">
-                        <i class="bi bi-shuffle text-success me-2"></i>
-                        Pseudo-random embedding
-                    </li>
-                    <li class="mb-1">
-                        <i class="bi bi-broadcast text-success me-2"></i>
-                        <strong>Channel keys</strong> for group isolation
-                        <span class="badge bg-info ms-1">v4.1</span>
-                    </li>
-                </ul>
-            </div>
-        </div>
-    </div>
 </div>
 {% endblock %}

instance/.secret_key

@@ -1 +0,0 @@
-6a7378172fc0ec37143720f09a4ca34e83ec2409893aa8cd79ace5b78a64276c

pyproject.toml

@@ -4,11 +4,11 @@ build-backend = "hatchling.build"
 
 [project]
 name = "stegasoo"
-version = "4.1.2"
+version = "4.2.0"
 description = "Secure steganography with hybrid photo + passphrase + PIN authentication"
 readme = "README.md"
 license = "MIT"
-requires-python = ">=3.10"
+requires-python = ">=3.11"
 authors = [
     { name = "Aaron D. Lee" }
 ]
@@ -29,9 +29,10 @@ classifiers = [
     "License :: OSI Approved :: MIT License",
     "Operating System :: OS Independent",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
     "Topic :: Security :: Cryptography",
     "Topic :: Multimedia :: Graphics",
 ]
@@ -40,6 +41,7 @@ dependencies = [
     "pillow>=10.0.0",
     "cryptography>=41.0.0",
     "argon2-cffi>=23.0.0",
+    "zstandard>=0.22.0",  # v4.2.0: Default compression algorithm
 ]
 
 [project.optional-dependencies]
@@ -47,7 +49,7 @@ dependencies = [
 dct = [
     "numpy>=2.0.0",
     "scipy>=1.10.0",
-    "jpegio>=0.2.0",
+    "jpeglib>=1.0.0",
     "reedsolo>=1.7.0",
 ]
 cli = [
@@ -57,7 +59,7 @@ cli = [
     "rich>=13.0.0",
 ]
 compression = [
-    "lz4>=4.0.0",
+    "lz4>=4.0.0",  # Optional: faster but slightly worse ratio than zstd
 ]
 web = [
     "flask>=3.0.0",
@@ -68,7 +70,7 @@ web = [
     # Include DCT support for web UI
     "numpy>=2.0.0",
     "scipy>=1.10.0",
-    "jpegio>=0.2.0",
+    "jpeglib>=1.0.0",
     "reedsolo>=1.7.0",
 ]
 api = [
@@ -80,7 +82,7 @@ api = [
     # Include DCT support for API
     "numpy>=2.0.0",
     "scipy>=1.10.0",
-    "jpegio>=0.2.0",
+    "jpeglib>=1.0.0",
     "reedsolo>=1.7.0",
 ]
 all = [
@@ -110,7 +112,7 @@ include = [
 ]
 
 [tool.hatch.build.targets.wheel]
-packages = ["src/stegasoo"]
+packages = ["src/stegasoo", "frontends"]
 
 [tool.pytest.ini_options]
 testpaths = ["tests"]
@@ -119,7 +121,7 @@ addopts = "-v --cov=stegasoo --cov-report=term-missing"
 
 [tool.black]
 line-length = 100
-target-version = ["py310", "py311", "py312"]
+target-version = ["py311", "py312", "py313"]
 
 [tool.ruff]
 line-length = 100
@@ -136,7 +138,7 @@ ignore = ["E501"]
 "src/stegasoo/__init__.py" = ["E402"]
 
 [tool.mypy]
-python_version = "3.10"
+python_version = "3.11"
 warn_return_any = true
 warn_unused_configs = true
 ignore_missing_imports = true

rpi/BUILD_IMAGE.md

@@ -26,51 +26,50 @@ ssh admin@stegasoo.local
 ## Step 3: Pre-Setup
 
 ```bash
-# Take ownership of /opt (for pyenv, jpegio builds)
+# Take ownership of /opt
 sudo chown admin:admin /opt
 
-# Install git and zstd (not included in Lite image)
-sudo apt-get update && sudo apt-get install -y git zstd jq
+# Install git (not included in Lite image)
+sudo apt-get update && sudo apt-get install -y git
 ```
 
 ## Step 4: Clone Repo
 
 ```bash
 cd /opt
-git clone -b 4.1 https://github.com/adlee-was-taken/stegasoo.git stegasoo
+git clone -b 4.2 https://github.com/adlee-was-taken/stegasoo.git stegasoo
 ```
 
-## Step 5: Copy Pre-built Tarball (from host)
-
-> **Dev-only asset:** This tarball is for building Pi images, not for end users.
-> It's available on [Releases](https://github.com/adlee-was-taken/stegasoo/releases) for image builders.
-
-```bash
-# On your host machine:
-scp rpi/stegasoo-pi-arm64.tar.zst admin@stegasoo.local:/opt/stegasoo/rpi/
-```
-
-This tarball contains:
-- pyenv with Python 3.12 (pre-compiled for ARM64)
-- venv with all dependencies (jpegio, scipy, etc.)
-
-Install time: **~2 minutes** (vs 20+ min from source)
-
-## Step 6: Run Setup
+## Step 5: Run Setup
 
 ```bash
 cd /opt/stegasoo
-./rpi/setup.sh  # Detects local tarball, skips download
+./rpi/setup.sh
 ```
 
-### From-Source Build (optional)
+The setup script:
+- Verifies Python 3.11+ (system Python, no pyenv needed)
+- Installs dependencies via apt and pip
+- jpeglib installs cleanly (no ARM patching like jpegio)
+- Creates and enables systemd service
+
+Install time: **5-10 minutes** (from source)
+
+### Pre-built Venv (optional)
+
+For faster installs, you can provide a pre-built venv tarball:
 
-To build without the pre-built tarball:
 ```bash
-./rpi/setup.sh --no-prebuilt  # Takes 15-20 minutes
+# On your host machine:
+scp rpi/stegasoo-rpi-venv-arm64.tar.zst admin@stegasoo.local:/opt/stegasoo/rpi/
+
+# Then on Pi:
+cd /opt/stegasoo && ./rpi/setup.sh  # Detects local tarball, skips pip build
 ```
 
-## Step 7: Test It Works
+Install time with pre-built: **~2 minutes**
+
+## Step 6: Test It Works
 
 ```bash
 sudo systemctl start stegasoo
@@ -78,7 +77,7 @@ curl -k https://localhost:5000
 # Should return HTML
 ```
 
-## Step 8: Sanitize for Distribution
+## Step 7: Sanitize for Distribution
 
 ```bash
 # Full sanitize (for final image - removes WiFi, shuts down)
@@ -98,7 +97,7 @@ This removes:
 
 The script validates all cleanup steps before finishing.
 
-## Step 9: Copy the Image
+## Step 8: Pull the Image
 
 Remove SD card, insert into your Linux machine:
 
@@ -106,23 +105,13 @@ Remove SD card, insert into your Linux machine:
 # Find the SD card device (CAREFUL!)
 lsblk
 
-# Copy (replace sdX with actual device, e.g., sda)
-sudo dd if=/dev/sdX of=stegasoo-rpi-$(date +%Y%m%d).img bs=4M status=progress
+# Pull image (auto-resizes to 16GB, compresses with zstd)
+sudo ./rpi/pull-image.sh /dev/sdX stegasoo-rpi-4.2.0.img.zst
 ```
 
-## Step 10: Shrink & Compress
+The script automatically resizes rootfs to 16GB (for smaller download), preserves auto-expand, and compresses.
 
-```bash
-# Optional: Shrink image (saves space)
-wget https://raw.githubusercontent.com/Drewsif/PiShrink/master/pishrink.sh
-chmod +x pishrink.sh
-sudo ./pishrink.sh stegasoo-rpi-*.img
-
-# Compress (zstd is faster than xz with similar ratio)
-zstd -19 -T0 stegasoo-rpi-*.img
-```
-
-## Step 11: Distribute
+## Step 9: Distribute
 
 Upload `.img.zst` to GitHub Releases.
 
@@ -140,36 +129,31 @@ zstdcat stegasoo-rpi-*.img.zst | sudo dd of=/dev/sdX bs=4M status=progress
 
 ---
 
-## Creating the Pre-built Tarball
+## Creating the Pre-built Venv Tarball
 
 After a successful from-source build, create the pre-built tarball for future installs:
 
 ```bash
 # On the Pi after successful setup:
-cd ~
+cd /opt/stegasoo
 
-# Strip caches and tests from venv (295MB → 208MB)
-find /opt/stegasoo/venv/ -type d -name '__pycache__' -exec rm -rf {} + 2>/dev/null
-find /opt/stegasoo/venv/ -type d -name 'tests' -exec rm -rf {} + 2>/dev/null
-find /opt/stegasoo/venv/ -type d -name 'test' -exec rm -rf {} + 2>/dev/null
+# Strip caches and tests from venv (saves ~100MB)
+find venv/ -type d -name '__pycache__' -exec rm -rf {} + 2>/dev/null
+find venv/ -type d -name 'tests' -exec rm -rf {} + 2>/dev/null
+find venv/ -type d -name 'test' -exec rm -rf {} + 2>/dev/null
 
 # Create venv tarball
-cd /opt/stegasoo
-tar -cf - venv/ | zstd -19 -T0 > ~/stegasoo-venv.tar.zst
+tar -cf - venv/ | zstd -19 -T0 > /tmp/stegasoo-rpi-venv-arm64.tar.zst
 
-# Create combined tarball (pyenv + venv pointer)
-cd ~
-tar -cf - .pyenv stegasoo-venv.tar.zst | zstd -19 -T0 > /tmp/stegasoo-pi-arm64.tar.zst
-
-# Check size (should be ~50-60MB)
-ls -lh /tmp/stegasoo-pi-arm64.tar.zst
+# Check size (should be ~40-50MB)
+ls -lh /tmp/stegasoo-rpi-venv-arm64.tar.zst
 ```
 
 Pull to host and upload to GitHub releases:
 ```bash
 # On host:
-scp admin@stegasoo.local:/tmp/stegasoo-pi-arm64.tar.zst ./
-# Upload to GitHub releases as stegasoo-pi-arm64.tar.zst
+scp admin@stegasoo.local:/tmp/stegasoo-rpi-venv-arm64.tar.zst ./rpi/
+# Upload to GitHub releases as stegasoo-rpi-venv-arm64.tar.zst
 ```
 
 ---
@@ -179,19 +163,15 @@ scp admin@stegasoo.local:/tmp/stegasoo-pi-arm64.tar.zst ./
 ```bash
 # On Pi (after SSH):
 sudo chown admin:admin /opt
-sudo apt-get update && sudo apt-get install -y git zstd jq
-cd /opt && git clone -b 4.1 https://github.com/adlee-was-taken/stegasoo.git stegasoo
+sudo apt-get update && sudo apt-get install -y git
+cd /opt && git clone -b 4.2 https://github.com/adlee-was-taken/stegasoo.git stegasoo
 
-# On host (copy tarball):
-scp rpi/stegasoo-pi-arm64.tar.zst admin@stegasoo.local:/opt/stegasoo/rpi/
-
-# On Pi (run setup):
+# Run setup:
 cd /opt/stegasoo && ./rpi/setup.sh
 sudo systemctl start stegasoo
 curl -k https://localhost:5000
 sudo /opt/stegasoo/rpi/sanitize-for-image.sh
 
-# On host (pull image):
-sudo dd if=/dev/sdX of=stegasoo-rpi-$(date +%Y%m%d).img bs=4M status=progress
-zstd -19 -T0 stegasoo-rpi-*.img
+# On host (pull image - auto-resizes to 16GB):
+sudo ./rpi/pull-image.sh /dev/sdX stegasoo-rpi-4.2.0.img.zst
 ```

rpi/README.md

@@ -4,7 +4,7 @@ Scripts and resources for deploying Stegasoo on Raspberry Pi.
 
 ## Quick Install
 
-On a fresh Raspberry Pi OS Lite (64-bit) installation:
+On a fresh Raspberry Pi OS (64-bit) installation:
 
 ```bash
 # Pre-setup (git not included in Lite image)
@@ -13,16 +13,16 @@ sudo apt-get update && sudo apt-get install -y git
 
 # Clone and run setup
 cd /opt
-git clone -b 4.1 https://github.com/adlee-was-taken/stegasoo.git stegasoo
+git clone -b 4.2 https://github.com/adlee-was-taken/stegasoo.git stegasoo
 cd stegasoo
 ./rpi/setup.sh
 ```
 
 ## What the Setup Script Does
 
-1. **Installs system dependencies** - build tools, libraries
-2. **Installs Python 3.12** - via pyenv (Pi OS ships with 3.13 which is incompatible)
-3. **Builds jpegio for ARM** - patches x86-specific flags
+1. **Verifies Python 3.11+** - uses system Python (no pyenv needed)
+2. **Installs system dependencies** - build tools, libraries
+3. **Installs jpeglib** - DCT steganography (Python 3.11-3.14 compatible)
 4. **Installs Stegasoo** - with web UI and all dependencies
 5. **Creates systemd service** - auto-starts on boot
 6. **Enables the service** - ready to start
@@ -30,11 +30,18 @@ cd stegasoo
 ## Requirements
 
 - Raspberry Pi 4 or 5
-- Raspberry Pi OS Lite (64-bit) - Bookworm or later
+- Raspberry Pi OS (64-bit) - Bookworm (Python 3.11) or Trixie (Python 3.13)
 - 4GB+ RAM recommended (2GB minimum)
-- ~2GB free disk space
+- 16GB+ SD card (pre-built images are 16GB)
 - Internet connection
 
+### Python Compatibility
+
+| Raspberry Pi OS | Python | Supported |
+|-----------------|--------|-----------|
+| Bookworm        | 3.11   | Yes       |
+| Trixie          | 3.13   | Yes       |
+
 ### Performance
 
 On a Pi 4 at 2GHz with USB 3.0 NVMe, expect ~60 seconds to encode/decode a 10MB JPEG with full encryption (passphrase + PIN + reference photo).
@@ -49,6 +56,25 @@ If using a pre-built image from GitHub Releases:
 
 > **Security note**: Change the default password after setup with `passwd`
 
+## Updating an Existing Installation
+
+To update to the latest version:
+
+```bash
+cd /opt/stegasoo
+git pull origin main
+sudo systemctl restart stegasoo
+```
+
+That's it - the editable install means Python uses the source directly.
+
+**If dependencies changed** (check release notes), also run:
+```bash
+source venv/bin/activate
+pip install -e ".[web]"
+sudo systemctl restart stegasoo
+```
+
 ## After Installation
 
 ### Start the Service
@@ -140,7 +166,7 @@ sudo apt-get update && sudo apt-get install -y git
 
 # Clone and run setup
 cd /opt
-git clone -b 4.1 https://github.com/adlee-was-taken/stegasoo.git stegasoo
+git clone -b 4.2 https://github.com/adlee-was-taken/stegasoo.git stegasoo
 cd stegasoo
 ./rpi/setup.sh
 ```
@@ -180,18 +206,15 @@ After Pi shuts down, remove SD card and on another Linux machine:
 # Find SD card device (BE CAREFUL - wrong device = data loss!)
 lsblk
 
-# Copy (replace sdX with your SD card)
-sudo dd if=/dev/sdX of=stegasoo-rpi-$(date +%Y%m%d).img bs=4M status=progress
-
-# Shrink the image (optional but recommended)
-wget https://raw.githubusercontent.com/Drewsif/PiShrink/master/pishrink.sh
-chmod +x pishrink.sh
-sudo ./pishrink.sh stegasoo-rpi-*.img
-
-# Compress (zstd is faster than xz with similar compression)
-zstd -19 -T0 stegasoo-rpi-*.img
+# Pull image (auto-resizes to 16GB, compresses with zstd)
+sudo ./rpi/pull-image.sh /dev/sdX stegasoo-rpi-4.2.0.img.zst
 ```
 
+The `pull-image.sh` script automatically:
+- Resizes rootfs to exactly 16GB (for smaller download)
+- Preserves auto-expand (image fills SD card on first boot)
+- Compresses with zstd for fast decompression
+
 ### 6. Distribute
 
 Upload the `.img.zst` file to GitHub Releases.

rpi/banner.sh

@@ -0,0 +1,63 @@
+#!/bin/bash
+# Stegasoo Banner/Header Template
+# Source this file to use the banner functions
+#
+# Usage:
+#   source "$(dirname "${BASH_SOURCE[0]}")/banner.sh"
+#   print_banner "Raspberry Pi Setup"
+#   print_gradient_line
+
+# Colors
+STEGASOO_GOLD='\033[38;5;220m'
+STEGASOO_GRAY='\033[0;90m'
+STEGASOO_WHITE='\033[1;37m'
+STEGASOO_GREEN='\033[0;32m'
+STEGASOO_NC='\033[0m'
+
+# Gradient line (purple -> blue)
+print_gradient_line() {
+    echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
+}
+
+# Starfield decoration line
+print_starfield() {
+    echo -e "${STEGASOO_GRAY} · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·${STEGASOO_NC}"
+}
+
+# ASCII logo (gold)
+print_logo() {
+    echo -e "${STEGASOO_GOLD}    ___  _____  ___    ___    _    ___    ___    ___${STEGASOO_NC}"
+    echo -e "${STEGASOO_GOLD}   / __||_   _|| __|  / __|  /_\\  / __|  / _ \\  / _ \\\\${STEGASOO_NC}"
+    echo -e "${STEGASOO_GOLD}   \\__ \\  | |  | _|  | (_ | / _ \\ \\__ \\ | (_) || (_) |${STEGASOO_NC}"
+    echo -e "${STEGASOO_GOLD}   |___/  |_|  |___|  \\___//_/ \\_\\|___/  \\___/  \\___/${STEGASOO_NC}"
+}
+
+# Full banner with optional subtitle
+# Usage: print_banner "Subtitle Text"
+print_banner() {
+    local subtitle="$1"
+    echo ""
+    print_gradient_line
+    print_starfield
+    print_logo
+    print_starfield
+    print_gradient_line
+    if [ -n "$subtitle" ]; then
+        echo -e "${STEGASOO_WHITE}                    ${subtitle}${STEGASOO_NC}"
+        print_gradient_line
+    fi
+}
+
+# Completion banner (green title)
+# Usage: print_complete_banner "Setup Complete!"
+print_complete_banner() {
+    local title="$1"
+    echo ""
+    print_gradient_line
+    print_starfield
+    print_logo
+    print_starfield
+    print_gradient_line
+    echo -e "\033[1;32m                      ${title}\033[0m"
+    print_gradient_line
+}

rpi/build-runtime-tarball.sh

@@ -0,0 +1,70 @@
+#!/bin/bash
+#
+# Build Stegasoo Pi venv Tarball
+# Run this ON THE PI after a successful from-source build
+#
+# Creates: stegasoo-rpi-venv-arm64.tar.zst (~40-50MB)
+# Contains: venv with all dependencies (uses system Python 3.11+)
+#
+
+set -e
+
+# Colors
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m'
+
+INSTALL_DIR="${INSTALL_DIR:-/opt/stegasoo}"
+OUTPUT_FILE="${1:-$HOME/stegasoo-rpi-venv-arm64.tar.zst}"
+
+echo -e "${GREEN}╔═══════════════════════════════════════════════════════════════╗${NC}"
+echo -e "${GREEN}║         Stegasoo Pi venv Tarball Builder                      ║${NC}"
+echo -e "${GREEN}╚═══════════════════════════════════════════════════════════════╝${NC}"
+echo ""
+
+# Verify we're on ARM64
+ARCH=$(uname -m)
+if [[ "$ARCH" != "aarch64" ]]; then
+    echo -e "${RED}Error: This script must be run on ARM64 (aarch64)${NC}"
+    echo "Current architecture: $ARCH"
+    exit 1
+fi
+
+# Verify venv exists
+if [[ ! -d "$INSTALL_DIR/venv" ]]; then
+    echo -e "${RED}Error: venv not found at $INSTALL_DIR/venv${NC}"
+    echo "Run a from-source build first: ./rpi/setup.sh --no-prebuilt"
+    exit 1
+fi
+
+# Step 1: Clean caches from venv
+echo -e "${GREEN}[1/2]${NC} Cleaning caches from venv..."
+VENV_SIZE_BEFORE=$(du -sh "$INSTALL_DIR/venv" | cut -f1)
+find "$INSTALL_DIR/venv/" -type d -name '__pycache__' -exec rm -rf {} + 2>/dev/null || true
+find "$INSTALL_DIR/venv/" -type d -name 'tests' -exec rm -rf {} + 2>/dev/null || true
+find "$INSTALL_DIR/venv/" -type d -name 'test' -exec rm -rf {} + 2>/dev/null || true
+find "$INSTALL_DIR/venv/" -type f -name '*.pyc' -delete 2>/dev/null || true
+VENV_SIZE_AFTER=$(du -sh "$INSTALL_DIR/venv" | cut -f1)
+echo "  venv: $VENV_SIZE_BEFORE -> $VENV_SIZE_AFTER"
+
+# Step 2: Create tarball
+echo -e "${GREEN}[2/2]${NC} Creating tarball..."
+cd "$INSTALL_DIR"
+tar -cf - venv/ | zstd -19 -T0 > "$OUTPUT_FILE"
+
+# Summary
+FINAL_SIZE=$(ls -lh "$OUTPUT_FILE" | awk '{print $5}')
+echo ""
+echo -e "${GREEN}════════════════════════════════════════════════════════════════${NC}"
+echo -e "  Output: ${YELLOW}$OUTPUT_FILE${NC}"
+echo -e "  Size:   ${YELLOW}$FINAL_SIZE${NC}"
+echo -e "${GREEN}════════════════════════════════════════════════════════════════${NC}"
+echo ""
+echo "To pull to your host machine:"
+echo "  scp $(whoami)@$(hostname).local:$OUTPUT_FILE ./"
+echo ""
+echo "To use in setup.sh, place at:"
+echo "  rpi/stegasoo-rpi-venv-arm64.tar.zst"
+echo ""
+echo "Or upload to GitHub releases for automatic download."

rpi/first-boot-wizard.sh

@@ -14,6 +14,10 @@
 INSTALL_DIR="/opt/stegasoo"
 FLAG_FILE="/etc/stegasoo-first-boot"
 PROFILE_HOOK="/etc/profile.d/stegasoo-wizard.sh"
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+# Source banner functions
+source "$SCRIPT_DIR/banner.sh"
 
 # Check if this is first boot
 if [ ! -f "$FLAG_FILE" ]; then
@@ -39,25 +43,58 @@ clear
 # Welcome
 # =============================================================================
 
+print_banner "First Boot Wizard"
 echo ""
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-echo -e "\033[0;90m · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·\033[0m"
-echo -e "\033[38;5;220m    ___  _____  ___    ___    _    ___    ___    ___\033[0m"
-echo -e "\033[38;5;220m   / __||_   _|| __|  / __|  /_\\  / __|  / _ \\  / _ \\\\\033[0m"
-echo -e "\033[38;5;220m   \\__ \\  | |  | _|  | (_ | / _ \\ \\__ \\ | (_) || (_) |\033[0m"
-echo -e "\033[38;5;220m   |___/  |_|  |___|  \\___//_/ \\_\\|___/  \\___/  \\___/\033[0m"
-echo -e "\033[0;90m · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·\033[0m"
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-echo -e "\033[1;37m                    First Boot Wizard\033[0m"
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-
+gum style --foreground 245 "This wizard will help you configure your Stegasoo server"
 echo ""
-gum style --foreground 245 "This wizard will help you configure your Stegasoo server."
-gum style --foreground 245 "You can reconfigure later by editing /etc/systemd/system/stegasoo.service"
+gum style --foreground 245 "You can reconfigure later by editing:"
+gum style --foreground 214 "  /etc/systemd/system/stegasoo.service"
 echo ""
 
 gum confirm "Ready to begin setup?" || exit 0
 
+# =============================================================================
+# Step 0: Expand Filesystem
+# =============================================================================
+
+clear
+gum style \
+  --foreground 212 --bold \
+  "Step 0: Expand Filesystem"
+echo ""
+
+# Get current and total size
+ROOT_DEV=$(findmnt -n -o SOURCE /)
+CURRENT_SIZE=$(df -h / | awk 'NR==2 {print $2}')
+TOTAL_SIZE=$(lsblk -b -d -o SIZE $(echo "$ROOT_DEV" | sed 's/[0-9]*$//') 2>/dev/null | tail -1 | awk '{printf "%.0fG", $1/1024/1024/1024}')
+
+gum style --foreground 245 "\
+The filesystem is currently $CURRENT_SIZE but your SD card may be larger.
+Expanding will use all available space on the SD card."
+echo ""
+gum style --foreground 245 "Current: $CURRENT_SIZE"
+echo ""
+
+if gum confirm "Expand filesystem to fill SD card?" --default=true; then
+  # Get the disk device (strip partition number) and partition number
+  DISK_DEV=$(echo "$ROOT_DEV" | sed 's/p\?[0-9]*$//')
+  PART_NUM=$(echo "$ROOT_DEV" | grep -o '[0-9]*$')
+
+  echo ""
+  gum style --foreground 245 "Expanding partition..."
+  sudo growpart "$DISK_DEV" "$PART_NUM" 2>&1 || true
+
+  gum style --foreground 245 "Expanding filesystem..."
+  sudo resize2fs "$ROOT_DEV" 2>&1
+
+  NEW_SIZE=$(df -h / | awk 'NR==2 {print $2}')
+  echo ""
+  gum style --foreground 82 "✓ Expanded to: $NEW_SIZE"
+else
+  gum style --foreground 214 "→ Skipped (run 'sudo growpart /dev/sdX 2 && sudo resize2fs /dev/sdX2' later)"
+fi
+sleep 1
+
 # =============================================================================
 # Configuration Variables
 # =============================================================================
@@ -142,52 +179,100 @@ This is useful if you want to share encoded images only with
 specific people (family, team, etc)."
 echo ""
 
-if gum confirm "Generate a private channel key?" --default=false; then
-  echo ""
-  # Generate key to temp file (gum spin doesn't capture stdout well)
-  KEY_FILE=$(mktemp)
-  ERR_FILE=$(mktemp)
-  VENV_PYTHON="$INSTALL_DIR/venv/bin/python"
-  gum spin --spinner dot --title "Generating channel key..." -- \
-    bash -c "'$VENV_PYTHON' -c 'from stegasoo.channel import generate_channel_key; print(generate_channel_key())' > '$KEY_FILE' 2>'$ERR_FILE'"
+CHANNEL_CHOICE=$(gum choose \
+  "Skip (public mode)" \
+  "Generate new key" \
+  "Enter existing key")
 
-  CHANNEL_KEY=$(cat "$KEY_FILE" 2>/dev/null | head -1)
-  KEY_ERROR=$(cat "$ERR_FILE" 2>/dev/null)
-  rm -f "$KEY_FILE" "$ERR_FILE"
+case "$CHANNEL_CHOICE" in
+  "Generate new key")
+    echo ""
+    # Generate key to temp file (gum spin doesn't capture stdout well)
+    KEY_FILE=$(mktemp)
+    ERR_FILE=$(mktemp)
+    VENV_PYTHON="$INSTALL_DIR/venv/bin/python"
+    gum spin --spinner dot --title "Generating channel key..." -- \
+      bash -c "'$VENV_PYTHON' -c 'from stegasoo.channel import generate_channel_key; print(generate_channel_key())' > '$KEY_FILE' 2>'$ERR_FILE'"
 
-  if [ -n "$CHANNEL_KEY" ] && [[ "$CHANNEL_KEY" =~ ^[A-Za-z0-9] ]]; then
-    echo ""
-    gum style --foreground 82 "✓ Channel key generated!"
-    echo ""
-    gum style \
-      --border rounded \
-      --border-foreground 226 \
-      --padding "1 2" \
-      --foreground 226 --bold \
-      "$CHANNEL_KEY"
-    echo ""
-    gum style --foreground 196 --bold \
-      "*** IMPORTANT: Write down or copy this key NOW! ***"
-    gum style --foreground 196 \
-      "You'll need to share it with anyone who should decode" \
-      "your images. This key won't be shown again."
-    echo ""
-    gum confirm "I've saved the key" --default=true --affirmative="Continue" --negative=""
-  else
-    gum style --foreground 196 "Failed to generate key. Using public mode."
-    if [ -n "$KEY_ERROR" ]; then
+    CHANNEL_KEY=$(cat "$KEY_FILE" 2>/dev/null | head -1)
+    KEY_ERROR=$(cat "$ERR_FILE" 2>/dev/null)
+    rm -f "$KEY_FILE" "$ERR_FILE"
+
+    if [ -n "$CHANNEL_KEY" ] && [[ "$CHANNEL_KEY" =~ ^[A-Za-z0-9] ]]; then
       echo ""
-      gum style --foreground 245 "Error details:"
-      echo "$KEY_ERROR"
+      gum style --foreground 82 "✓ Channel key generated!"
+      echo ""
+      gum style \
+        --border rounded \
+        --border-foreground 226 \
+        --padding "1 2" \
+        --foreground 226 --bold \
+        "$CHANNEL_KEY"
+      echo ""
+      gum style --foreground 196 --bold \
+        "*** IMPORTANT: Write down or copy this key NOW! ***"
+      gum style --foreground 196 \
+        "You'll need to share it with anyone who should decode" \
+        "your images. This key won't be shown again."
+      echo ""
+      gum confirm "I've saved the key" --default=true --affirmative="Continue" --negative=""
+    else
+      gum style --foreground 196 "Failed to generate key. Using public mode."
+      if [ -n "$KEY_ERROR" ]; then
+        echo ""
+        gum style --foreground 245 "Error details:"
+        echo "$KEY_ERROR"
+      fi
+      CHANNEL_KEY=""
+      echo ""
+      gum confirm "Continue" --default=true --affirmative="OK" --negative=""
     fi
-    CHANNEL_KEY=""
+    ;;
+
+  "Enter existing key")
     echo ""
-    gum confirm "Continue" --default=true --affirmative="OK" --negative=""
-  fi
-else
-  gum style --foreground 214 "→ Using public mode"
-  sleep 0.5
-fi
+    gum style --foreground 245 "Enter the channel key from your team/deployment."
+    gum style --foreground 245 "Format: XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX"
+    echo ""
+
+    while true; do
+      ENTERED_KEY=$(gum input --placeholder "ABCD-1234-EFGH-5678-IJKL-9012-MNOP-3456" --width 50)
+
+      if [ -z "$ENTERED_KEY" ]; then
+        gum style --foreground 214 "→ Cancelled, using public mode"
+        CHANNEL_KEY=""
+        break
+      fi
+
+      # Validate the key using Python
+      VENV_PYTHON="$INSTALL_DIR/venv/bin/python"
+      if "$VENV_PYTHON" -c "from stegasoo.channel import validate_channel_key, format_channel_key; k='$ENTERED_KEY'; exit(0 if validate_channel_key(k) else 1)" 2>/dev/null; then
+        # Get formatted key
+        CHANNEL_KEY=$("$VENV_PYTHON" -c "from stegasoo.channel import format_channel_key; print(format_channel_key('$ENTERED_KEY'))" 2>/dev/null)
+        echo ""
+        gum style --foreground 82 "✓ Channel key accepted!"
+        gum style --foreground 245 "Key: $CHANNEL_KEY"
+        break
+      else
+        echo ""
+        gum style --foreground 196 "Invalid key format. Please check and try again."
+        gum style --foreground 245 "Expected: 32 alphanumeric characters (with or without dashes)"
+        echo ""
+        if ! gum confirm "Try again?" --default=true; then
+          gum style --foreground 214 "→ Using public mode"
+          CHANNEL_KEY=""
+          break
+        fi
+      fi
+    done
+    ;;
+
+  *)
+    gum style --foreground 214 "→ Using public mode"
+    CHANNEL_KEY=""
+    sleep 0.5
+    ;;
+esac
 
 # =============================================================================
 # Step 4: Overclock Configuration
@@ -407,22 +492,11 @@ else
 fi
 
 echo ""
-echo ""
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-echo -e "\033[0;90m · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·\033[0m"
-echo -e "\033[38;5;220m    ___  _____  ___    ___    _    ___    ___    ___\033[0m"
-echo -e "\033[38;5;220m   / __||_   _|| __|  / __|  /_\\  / __|  / _ \\  / _ \\\\\033[0m"
-echo -e "\033[38;5;220m   \\__ \\  | |  | _|  | (_ | / _ \\ \\__ \\ | (_) || (_) |\033[0m"
-echo -e "\033[38;5;220m   |___/  |_|  |___|  \\___//_/ \\_\\|___/  \\___/  \\___/\033[0m"
-echo -e "\033[0;90m · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·\033[0m"
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-echo -e "\033[1;32m                      Setup Complete!\033[0m"
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-
+print_complete_banner "Setup Complete!"
 echo ""
 gum style --foreground 82 --bold "Create your admin account:"
-gum style --foreground 226 "  $ACCESS_URL"
-gum style --foreground 245 "  $ACCESS_URL_LOCAL (if mDNS works)"
+gum style --foreground 226 "  $ACCESS_URL_LOCAL"
+gum style --foreground 245 "  $ACCESS_URL (fallback IP)"
 
 if [ -n "$CHANNEL_KEY" ]; then
   echo ""

rpi/flash-image.sh

@@ -80,9 +80,9 @@ if [ -z "$1" ]; then
     echo "Supported formats: .img, .img.zst, .img.xz, .img.gz, .img.zst.zip"
     echo ""
     echo "Examples:"
-    echo "  $0 stegasoo-rpi-4.1.1.img.zst             # auto-detect SD card"
-    echo "  $0 stegasoo-rpi-4.1.1.img.zst.zip         # from GitHub release"
-    echo "  $0 stegasoo-rpi-4.1.1.img.zst /dev/sdb    # specify device"
+    echo "  $0 stegasoo-rpi-4.2.0.img.zst             # auto-detect SD card"
+    echo "  $0 stegasoo-rpi-4.2.0.img.zst.zip         # from GitHub release"
+    echo "  $0 stegasoo-rpi-4.2.0.img.zst /dev/sdb    # specify device"
     exit 1
 fi
 
@@ -249,16 +249,9 @@ if [ -n "$MOUNTED" ]; then
     done
 fi
 
-# Ask about wiping
+# Ask about wiping (defer actual wipe until after final confirmation)
 echo
 read -p "Wipe partition table first? (recommended if having issues) [y/N] " wipe_confirm
-if [[ "$wipe_confirm" =~ ^[Yy]$ ]]; then
-    echo "Wiping partition table..."
-    sudo wipefs -a "$SELECTED"
-    sudo dd if=/dev/zero of="$SELECTED" bs=1M count=10 status=none
-    sync
-    echo "  Wiped clean"
-fi
 
 # Final confirmation
 echo -e "${RED}╔═══════════════════════════════════════════════════════════════╗${NC}"
@@ -272,73 +265,65 @@ if [[ ! $REPLY == "yes" ]]; then
     exit 1
 fi
 
+# Now wipe if requested
+if [[ "$wipe_confirm" =~ ^[Yy]$ ]]; then
+    echo "Wiping partition table..."
+    sudo wipefs -af "$SELECTED" 2>/dev/null || true
+    sync
+    echo "  Wiped"
+fi
+
 echo ""
 echo -e "${GREEN}Flashing image to $SELECTED...${NC}"
 echo ""
 
-# Try rpi-imager first (faster, native support for compressed images)
-if command -v rpi-imager &> /dev/null; then
-    echo -e "${YELLOW}Using rpi-imager...${NC}"
-    if rpi-imager --cli --disable-verify "$IMAGE" "$SELECTED"; then
-        # rpi-imager succeeded
-        :
-    else
-        echo -e "${YELLOW}rpi-imager failed, falling back to dd...${NC}"
-        # Fall through to dd
-        USE_DD=true
-    fi
+# Flash with dd (status=progress shows actual write progress)
+echo -e "${YELLOW}Flashing (this may take several minutes for SD cards)...${NC}"
+if [ "$COMPRESSED" = true ]; then
+    case "$COMP_TYPE" in
+        xz)  xzcat "$IMAGE" | sudo dd of="$SELECTED" bs=1M status=progress ;;
+        zst) zstdcat "$IMAGE" | sudo dd of="$SELECTED" bs=1M status=progress ;;
+        gz)  zcat "$IMAGE" | sudo dd of="$SELECTED" bs=1M status=progress ;;
+    esac
 else
-    USE_DD=true
-fi
-
-# Fallback to dd
-if [ "$USE_DD" = true ]; then
-    if [ "$HAS_PV" = true ]; then
-        echo -e "${YELLOW}Using dd with progress...${NC}"
-        if [ "$COMPRESSED" = true ]; then
-            case "$COMP_TYPE" in
-                xz)  pv "$IMAGE" | xzcat | dd of="$SELECTED" bs=4M conv=fsync 2>/dev/null ;;
-                zst) pv "$IMAGE" | zstdcat | dd of="$SELECTED" bs=4M conv=fsync 2>/dev/null ;;
-                gz)  pv "$IMAGE" | zcat | dd of="$SELECTED" bs=4M conv=fsync 2>/dev/null ;;
-            esac
-        else
-            pv "$IMAGE" | dd of="$SELECTED" bs=4M conv=fsync 2>/dev/null
-        fi
-    else
-        echo -e "${YELLOW}Using dd (no progress - install pv for progress bar)...${NC}"
-        if [ "$COMPRESSED" = true ]; then
-            case "$COMP_TYPE" in
-                xz)  xzcat "$IMAGE" | dd of="$SELECTED" bs=4M conv=fsync status=progress ;;
-                zst) zstdcat "$IMAGE" | dd of="$SELECTED" bs=4M conv=fsync status=progress ;;
-                gz)  zcat "$IMAGE" | dd of="$SELECTED" bs=4M conv=fsync status=progress ;;
-            esac
-        else
-            dd if="$IMAGE" of="$SELECTED" bs=4M conv=fsync status=progress
-        fi
-    fi
+    sudo dd if="$IMAGE" of="$SELECTED" bs=1M status=progress
 fi
 
 echo ""
 echo -e "${GREEN}Syncing...${NC}"
 sync
 
+# Wait for partitions to appear
+sleep 2
+partprobe "$SELECTED" 2>/dev/null || true
+sleep 1
+
+# Determine partition names
+if [[ "$SELECTED" == *"nvme"* ]] || [[ "$SELECTED" == *"mmcblk"* ]]; then
+    BOOT_PART="${SELECTED}p1"
+    ROOT_PART="${SELECTED}p2"
+else
+    BOOT_PART="${SELECTED}1"
+    ROOT_PART="${SELECTED}2"
+fi
+
+# Validate and repair filesystems
+echo ""
+echo -e "${YELLOW}Validating filesystems...${NC}"
+
+echo "  Checking boot partition ($BOOT_PART)..."
+sudo fsck.vfat -a "$BOOT_PART" 2>&1 | grep -v "^$" || true
+
+echo "  Checking root partition ($ROOT_PART)..."
+sudo e2fsck -f -y "$ROOT_PART" 2>&1 | tail -5 || true
+
+echo -e "${GREEN}  ✓ Filesystems validated${NC}"
+
 # Inject WiFi config if config.json was loaded
 if [ "$HAS_CONFIG" = true ]; then
     echo ""
     echo -e "${GREEN}Configuring WiFi from config.json...${NC}"
 
-    # Wait for partitions to appear
-    sleep 2
-    partprobe "$SELECTED" 2>/dev/null || true
-    sleep 1
-
-    # Determine boot partition
-    if [[ "$SELECTED" == *"nvme"* ]] || [[ "$SELECTED" == *"mmcblk"* ]]; then
-        BOOT_PART="${SELECTED}p1"
-    else
-        BOOT_PART="${SELECTED}1"
-    fi
-
     if [ -b "$BOOT_PART" ]; then
         MOUNT_DIR=$(mktemp -d)
         if mount "$BOOT_PART" "$MOUNT_DIR" 2>/dev/null; then

rpi/flash-stock-img.sh

@@ -120,28 +120,64 @@ read -p "Resize rootfs to 16GB for faster imaging? [Y/n] " resize_confirm
 if [[ ! "$resize_confirm" =~ ^[Nn]$ ]]; then
     echo "Resizing rootfs partition to 16GB..."
 
-    # Get boot partition end
+    # Get current partition size in bytes
+    CURRENT_SIZE=$(sudo blockdev --getsize64 "$ROOT_PART")
+    TARGET_BYTES=$((16 * 1024 * 1024 * 1024))  # 16GB in bytes
+
+    # Get boot partition end in sectors
     BOOT_END=$(sudo parted -s "$DEVICE" unit s print | grep "^ 1" | awk '{print $3}' | tr -d 's')
 
     # Calculate 16GB in sectors (512 byte sectors)
-    # 16GB = 16 * 1024 * 1024 * 1024 / 512 = 33554432 sectors
     ROOT_SIZE_SECTORS=33554432
     ROOT_END=$((BOOT_END + ROOT_SIZE_SECTORS))
 
-    # Delete and recreate partition 2 with fixed size
-    sudo parted -s "$DEVICE" rm 2
-    sudo parted -s "$DEVICE" mkpart primary ext4 $((BOOT_END + 1))s ${ROOT_END}s
+    if [ "$CURRENT_SIZE" -lt "$TARGET_BYTES" ]; then
+        # EXPANDING: partition first, then filesystem
+        echo "Current partition is smaller than 16GB - expanding..."
 
-    # Refresh partition table
-    sudo partprobe "$DEVICE"
-    sleep 1
+        # Delete and recreate partition 2 with 16GB size
+        echo "Expanding partition to 16GB..."
+        sudo parted -s "$DEVICE" rm 2
+        sudo parted -s "$DEVICE" mkpart primary ext4 $((BOOT_END + 1))s ${ROOT_END}s
 
-    # Check and resize filesystem
-    echo "Checking filesystem..."
-    sudo e2fsck -f -y "$ROOT_PART" 2>/dev/null || true
+        # Refresh partition table
+        sudo partprobe "$DEVICE"
+        sleep 2
 
-    echo "Resizing filesystem to fit partition..."
-    sudo resize2fs "$ROOT_PART"
+        # Expand filesystem to fill the new partition
+        echo "Expanding filesystem to fill partition..."
+        sudo e2fsck -f -y "$ROOT_PART" 2>/dev/null || true
+        sudo resize2fs "$ROOT_PART"
+    else
+        # SHRINKING: filesystem first, then partition
+        echo "Current partition is larger than 16GB - shrinking..."
+
+        # Check and shrink filesystem first
+        echo "Checking filesystem..."
+        sudo e2fsck -f -y "$ROOT_PART" 2>/dev/null || true
+
+        # Shrink filesystem to 15.5GB (leave room for partition overhead)
+        echo "Shrinking filesystem to 15500M..."
+        sudo resize2fs "$ROOT_PART" 15500M
+
+        # Delete and recreate partition 2 with 16GB size
+        echo "Shrinking partition to 16GB..."
+        sudo parted -s "$DEVICE" rm 2
+        sudo parted -s "$DEVICE" mkpart primary ext4 $((BOOT_END + 1))s ${ROOT_END}s
+
+        # Refresh partition table
+        sudo partprobe "$DEVICE"
+        sleep 2
+
+        # Expand filesystem to fill the partition exactly
+        echo "Expanding filesystem to fill partition..."
+        sudo e2fsck -f -y "$ROOT_PART" 2>/dev/null || true
+        sudo resize2fs "$ROOT_PART"
+    fi
+
+    # Verify and show result
+    echo "Verifying partition size..."
+    sudo parted -s "$DEVICE" unit GB print | grep "^ 2"
 
     # Disable Pi OS auto-expand on first boot
     echo "Disabling auto-expand..."
@@ -155,12 +191,10 @@ if [[ ! "$resize_confirm" =~ ^[Nn]$ ]]; then
     # Disable the systemd resize service
     sudo rm -f "$TEMP_ROOT/etc/systemd/system/multi-user.target.wants/rpi-resizerootfs.service"
 
-    # Remove init= parameter from cmdline.txt on boot partition (handled later)
-
     sudo umount "$TEMP_ROOT"
     rmdir "$TEMP_ROOT"
 
-    echo "  Rootfs resized to 16GB (auto-expand disabled)"
+    echo "  Rootfs set to 16GB (auto-expand disabled)"
 fi
 
 MOUNT_DIR=$(mktemp -d)
@@ -282,4 +316,17 @@ echo "  User: $PI_USER"
 echo "  SSH: enabled"
 echo "  WiFi: $WIFI_SSID"
 echo
-echo "Insert into Pi and boot. Find it with: ping $PI_HOSTNAME.local"
+echo "Insert into Pi and boot. Access via:"
+echo "  mDNS:  http://$PI_HOSTNAME.local"
+echo "  Find IP: ping $PI_HOSTNAME.local"
+echo
+echo "Once booted, SSH with: ssh $PI_USER@$PI_HOSTNAME.local"
+
+# If we resized, remind about pull-image.sh
+if [[ ! "$resize_confirm" =~ ^[Nn]$ ]]; then
+    echo
+    echo "=== After setup, use pull-image.sh to create distributable image ==="
+    echo "  ./pull-image.sh $DEVICE stegasoo-rpi-VERSION.img.zst"
+    echo
+    echo "This will only pull the 16GB partition, not the entire SD card."
+fi

rpi/host-requirements.txt

@@ -0,0 +1,29 @@
+# Host Machine Dependencies for Stegasoo Pi Scripts
+# =================================================
+#
+# Quick install (Debian/Ubuntu):
+#   sudo apt install parted e2fsprogs zstd zip bc pv jq unzip sshpass
+#
+# Or install with this file:
+#   sudo apt install $(grep -v '^#' rpi/host-requirements.txt | grep -v '^$' | xargs)
+
+# pull-image.sh - Create distributable images
+parted              # Partition table reading/writing
+e2fsprogs           # e2fsck, resize2fs for ext4
+zstd                # Compression (zstd -T0 -3)
+zip                 # Optional .zst.zip wrapper for GitHub
+bc                  # Floating point math for size display
+pv                  # Progress bar (optional, falls back to dd status)
+
+# flash-image.sh - Flash images to SD cards
+unzip               # Extract .zst.zip wrappers
+zstd                # Decompress .zst images
+pv                  # Progress bar (optional)
+jq                  # Parse config.json for headless WiFi (optional)
+
+# kickoff-pi-test.sh - Automated flash+test
+sshpass             # Non-interactive SSH with password
+avahi-utils         # avahi-resolve for .local hostname lookup
+
+# Optional tools
+rpi-imager          # Faster flashing (flash-image.sh falls back to dd)

rpi/patches/README.md

@@ -2,56 +2,39 @@
 
 This directory contains patches for dependencies that need modifications to build on ARM64.
 
+## Current Status (v4.2+)
+
+As of Stegasoo 4.2, we use **jpeglib** instead of jpegio. The jpeglib build process is handled inline in `setup.sh` and includes:
+
+- Cloning from GitHub (PyPI tarball missing headers)
+- Downloading libjpeg headers for each version (6b through 9f)
+- Patching setup.py to skip turbo/mozjpeg (need cmake-generated headers)
+
+See `setup.sh` for the full implementation.
+
+## Legacy: jpegio Patches (v4.1 and earlier)
+
+The `jpegio/` directory contains patches for the old jpegio dependency, which required removing x86-specific `-m64` compiler flags. These are no longer used but kept for reference.
+
+## jpeglib Helper Script
+
+The `jpeglib/install-jpeglib-arm64.sh` script is a standalone version of the jpeglib build process. It's not used by setup.sh (which has the logic inline) but can be useful for manual testing or debugging.
+
 ## Structure
 
 ```
 patches/
-  <package>/
-    arm64.patch       # Standard unified diff patch file
-    apply-patch.sh    # Script with fallback strategies
+  jpegio/           # Legacy (v4.1) - not used in v4.2+
+    arm64.patch
+    apply-patch.sh
+  jpeglib/          # Reference script for manual builds
+    install-jpeglib-arm64.sh
 ```
 
-## How It Works
+## Adding New Patches
 
-The `apply-patch.sh` script tries multiple strategies in order:
-
-1. **Patch file** - Apply the `.patch` file using `patch -p1`
-2. **Sed fallback** - Use sed for simple string replacements
-3. **Python fallback** - Use regex for flexible pattern matching
-
-This layered approach handles:
-- Exact matches (patch file works)
-- Minor upstream changes (sed catches variations)
-- Significant changes (Python regex is most flexible)
-- Already patched files (detected and skipped)
-
-## Adding a New Patch
+If a new dependency needs ARM64 patches:
 
 1. Create a directory: `patches/<package>/`
-2. Create the patch file: `git diff > arm64.patch`
-3. Create `apply-patch.sh` with appropriate fallback logic
-4. Update `setup.sh` to call the patch script
-
-## jpegio Patch
-
-The jpegio library includes x86-specific `-m64` compiler flags that fail on ARM64.
-The patch removes these flags by replacing:
-
-```python
-cargs.append('-m64')
-```
-
-with:
-
-```python
-pass  # ARM64: removed x86-specific -m64 flag
-```
-
-## Updating Patches
-
-When upstream changes break a patch:
-
-1. Clone the new version
-2. Make the necessary modifications
-3. Generate a new patch: `diff -u original modified > arm64.patch`
-4. Test on a fresh Pi install
+2. Add patch files or helper scripts
+3. Update `setup.sh` to apply the patch during installation

rpi/patches/jpeglib/install-jpeglib-arm64.sh

@@ -0,0 +1,57 @@
+#!/bin/bash
+#
+# Install jpeglib on ARM64 Linux (Raspberry Pi)
+# Works around missing headers in the source tarball
+#
+# Usage: ./install-jpeglib-arm64.sh
+#
+
+set -e
+
+echo "Installing jpeglib for ARM64..."
+
+# Create temp directory
+WORKDIR=$(mktemp -d)
+cd "$WORKDIR"
+
+# Download jpeglib source
+echo "  Downloading jpeglib source..."
+pip download jpeglib==1.0.2 --no-binary :all: --no-deps -d . -q
+tar -xzf jpeglib-1.0.2.tar.gz
+cd jpeglib-1.0.2
+
+# Download official libjpeg sources and copy headers
+echo "  Downloading libjpeg headers..."
+CJPEGLIB="src/jpeglib/cjpeglib"
+
+# libjpeg 6b
+curl -sL "https://www.ijg.org/files/jpegsrc.v6b.tar.gz" | tar -xzf -
+cp jpeg-6b/*.h "$CJPEGLIB/6b/"
+
+# libjpeg 7-9f (all use similar headers from 9e)
+curl -sL "https://www.ijg.org/files/jpegsrc.v9f.tar.gz" | tar -xzf -
+for v in 7 8 8a 8b 8c 8d 9 9a 9b 9c 9d 9e 9f; do
+    cp jpeg-9f/*.h "$CJPEGLIB/$v/"
+done
+
+# libjpeg-turbo versions
+curl -sL "https://github.com/libjpeg-turbo/libjpeg-turbo/archive/refs/tags/2.1.0.tar.gz" | tar -xzf -
+for v in turbo120 turbo130 turbo140 turbo150 turbo200 turbo210; do
+    cp libjpeg-turbo-2.1.0/*.h "$CJPEGLIB/$v/" 2>/dev/null || true
+done
+
+# mozjpeg versions
+curl -sL "https://github.com/mozilla/mozjpeg/archive/refs/tags/v4.0.3.tar.gz" | tar -xzf -
+for v in mozjpeg101 mozjpeg201 mozjpeg300 mozjpeg403; do
+    cp mozjpeg-4.0.3/*.h "$CJPEGLIB/$v/" 2>/dev/null || true
+done
+
+# Build and install
+echo "  Building jpeglib..."
+pip install . -q
+
+# Cleanup
+cd /
+rm -rf "$WORKDIR"
+
+echo "  Done! jpeglib installed successfully."

rpi/pull-image.sh

@@ -1,31 +1,26 @@
 #!/bin/bash
+# Pull Raspberry Pi image from SD card (after setup)
+# Resizes rootfs to 16GB for consistent image size, then pulls
 #
-# Pull Stegasoo image from SD card
-# Auto-detects SD card, copies with progress, shrinks, and compresses
-#
-# Usage: ./pull-image.sh [output-name] [device]
-#        Output will be: stegasoo-rpi-YYYYMMDD.img.zst (or custom name)
-#        Use .img extension to skip compression: ./pull-image.sh foo.img
-#
-# If device is specified, skips auto-detection (useful for large drives)
-#
+# Usage: ./pull-image.sh <device> <output.img.zst>
+# Example: ./pull-image.sh /dev/sdb stegasoo-rpi-4.2.0.img.zst
 
 set -e
 
 RED='\033[0;31m'
 GREEN='\033[0;32m'
 YELLOW='\033[1;33m'
-BLUE='\033[0;34m'
 BOLD='\033[1m'
 NC='\033[0m'
 
-# Check for required tools
-for cmd in dd pv zstd lsblk; do
-    if ! command -v $cmd &> /dev/null; then
-        echo -e "${RED}Error: $cmd is required but not installed.${NC}"
-        exit 1
-    fi
-done
+if [ $# -ne 2 ]; then
+    echo "Usage: $0 <device> <output.img.zst>"
+    echo "Example: $0 /dev/sdb stegasoo-rpi-4.2.0.img.zst"
+    exit 1
+fi
+
+DEVICE="$1"
+OUTPUT="$2"
 
 # Check for root
 if [ "$EUID" -ne 0 ]; then
@@ -33,204 +28,166 @@ if [ "$EUID" -ne 0 ]; then
     exit 1
 fi
 
-# Output filename and optional device
-if [ -n "$1" ]; then
-    OUTPUT="$1"
-else
-    OUTPUT="stegasoo-rpi-$(date +%Y%m%d).img.zst"
-fi
-MANUAL_DEVICE="$2"
-
-# Check if output ends in .img (skip compression) or .zst (compress)
-SKIP_COMPRESS=false
-if [[ "$OUTPUT" == *.img ]]; then
-    IMG_FILE="$OUTPUT"
-    SKIP_COMPRESS=true
-elif [[ "$OUTPUT" == *.zst ]]; then
-    IMG_FILE="${OUTPUT%.zst}"
-else
-    # No recognized extension, add .img.zst
-    IMG_FILE="${OUTPUT}.img"
-    OUTPUT="${OUTPUT}.img.zst"
+if [ ! -b "$DEVICE" ]; then
+    echo -e "${RED}Error: Device not found: $DEVICE${NC}"
+    exit 1
 fi
 
-echo -e "${BLUE}"
-echo "╔═══════════════════════════════════════════════════════════════╗"
-echo "║              Stegasoo SD Card Image Puller                    ║"
-echo "╚═══════════════════════════════════════════════════════════════╝"
-echo -e "${NC}"
-
-# Use manual device or auto-detect
-if [ -n "$MANUAL_DEVICE" ]; then
-    # Manual device specified
-    if [ ! -b "$MANUAL_DEVICE" ]; then
-        echo -e "${RED}Error: $MANUAL_DEVICE is not a block device${NC}"
-        exit 1
-    fi
-    SELECTED="$MANUAL_DEVICE"
-    echo -e "Using specified device: ${YELLOW}$SELECTED${NC}"
-    echo ""
-    lsblk "$SELECTED" -o NAME,SIZE,TYPE,MODEL
-    echo ""
-else
-    # Auto-detect SD card candidates
-    # Looking for: USB/removable, 8-128GB, not mounted as root filesystem
-    echo -e "${BOLD}Scanning for SD cards...${NC}"
-    echo ""
-
-    declare -a CANDIDATES
-    declare -a CANDIDATE_INFO
-
-    while IFS= read -r line; do
-        DEV=$(echo "$line" | awk '{print $1}')
-        SIZE=$(echo "$line" | awk '{print $2}')
-        TYPE=$(echo "$line" | awk '{print $3}')
-        TRAN=$(echo "$line" | awk '{print $4}')
-        MODEL=$(echo "$line" | awk '{print $5" "$6" "$7}' | xargs)
-
-        # Skip if it's the root filesystem
-        if mount | grep -q "^/dev/${DEV}[0-9]* on / "; then
-            continue
-        fi
-
-        # Skip if any partition is mounted as root
-        ROOT_DEV=$(mount | grep " on / " | awk '{print $1}' | sed 's/[0-9]*$//')
-        if [[ "/dev/$DEV" == "$ROOT_DEV" ]]; then
-            continue
-        fi
-
-        # Get size in bytes for reliable comparison
-        SIZE_BYTES=$(lsblk -b -d -o SIZE -n "/dev/$DEV" 2>/dev/null | tr -d ' ')
-        SIZE_GB_INT=$((SIZE_BYTES / 1073741824))  # 1024^3
-
-        # Check if size is in SD card range (8GB - 128GB)
-        if [ "$SIZE_GB_INT" -ge 8 ] && [ "$SIZE_GB_INT" -le 128 ]; then
-            CANDIDATES+=("/dev/$DEV")
-            CANDIDATE_INFO+=("$SIZE $TYPE ${TRAN:-???} $MODEL")
-        fi
-    done < <(lsblk -d -o NAME,SIZE,TYPE,TRAN,MODEL -n | grep "disk")
-
-    if [ ${#CANDIDATES[@]} -eq 0 ]; then
-        echo -e "${RED}No SD card candidates found.${NC}"
-        echo "Looking for USB/removable disks between 8GB and 128GB."
-        echo ""
-        echo "Available disks:"
-        lsblk -d -o NAME,SIZE,TYPE,TRAN,MODEL
-        echo ""
-        echo -e "${YELLOW}Tip: Specify device manually: $0 output.img.zst /dev/sdX${NC}"
-        exit 1
-    fi
-
-    echo -e "${GREEN}Found ${#CANDIDATES[@]} candidate(s):${NC}"
-    echo ""
-
-    for i in "${!CANDIDATES[@]}"; do
-        echo -e "  ${BOLD}[$((i+1))]${NC} ${CANDIDATES[$i]} - ${CANDIDATE_INFO[$i]}"
-    done
-
-    echo ""
-
-    if [ ${#CANDIDATES[@]} -eq 1 ]; then
-        SELECTED="${CANDIDATES[0]}"
-        echo -e "Auto-selected: ${YELLOW}$SELECTED${NC}"
-    else
-        read -p "Select device [1-${#CANDIDATES[@]}]: " -r
-        if [[ ! $REPLY =~ ^[0-9]+$ ]] || [ "$REPLY" -lt 1 ] || [ "$REPLY" -gt ${#CANDIDATES[@]} ]; then
-            echo -e "${RED}Invalid selection.${NC}"
-            exit 1
-        fi
-        SELECTED="${CANDIDATES[$((REPLY-1))]}"
-    fi
-fi
-
-# Show partitions
-echo ""
-echo -e "${BOLD}Partitions on $SELECTED:${NC}"
-lsblk "$SELECTED" -o NAME,SIZE,FSTYPE,LABEL,MOUNTPOINT
-echo ""
-
-# Final confirmation
-echo -e "${RED}╔═══════════════════════════════════════════════════════════════╗${NC}"
-echo -e "${RED}║  WARNING: This will read the ENTIRE device:                   ║${NC}"
-echo -e "${RED}║  $SELECTED                                                  ║${NC}"
-echo -e "${RED}╚═══════════════════════════════════════════════════════════════╝${NC}"
-echo ""
-echo -e "Output: ${YELLOW}$OUTPUT${NC}"
-echo ""
-read -p "Continue? [y/N] " -n 1 -r
+echo -e "${BOLD}Device info:${NC}"
+lsblk "$DEVICE"
 echo
-if [[ ! $REPLY =~ ^[Yy]$ ]]; then
+
+# Find partitions
+if [ -b "${DEVICE}1" ]; then
+    BOOT_PART="${DEVICE}1"
+    ROOT_PART="${DEVICE}2"
+elif [ -b "${DEVICE}p1" ]; then
+    BOOT_PART="${DEVICE}p1"
+    ROOT_PART="${DEVICE}p2"
+else
+    echo -e "${RED}Error: Could not find partitions${NC}"
+    exit 1
+fi
+
+# Unmount any mounted partitions
+echo -e "${YELLOW}Unmounting partitions...${NC}"
+umount "$BOOT_PART" 2>/dev/null || true
+umount "$ROOT_PART" 2>/dev/null || true
+
+# ============================================================================
+# Resize rootfs to 16GB
+# ============================================================================
+echo
+echo -e "${BOLD}Checking partition size...${NC}"
+
+# Get current partition size in bytes
+CURRENT_SIZE=$(blockdev --getsize64 "$ROOT_PART")
+TARGET_BYTES=$((16 * 1024 * 1024 * 1024))  # 16GB in bytes
+CURRENT_GB=$(echo "scale=2; $CURRENT_SIZE / 1073741824" | bc)
+
+echo "  Current rootfs size: ${CURRENT_GB}GB"
+
+if [ "$CURRENT_SIZE" -gt "$TARGET_BYTES" ]; then
+    echo -e "${YELLOW}Resizing rootfs to 16GB...${NC}"
+
+    # Get boot partition end in sectors
+    BOOT_END=$(parted -s "$DEVICE" unit s print | grep "^ 1" | awk '{print $3}' | tr -d 's')
+
+    # Calculate 16GB in sectors (512 byte sectors)
+    ROOT_SIZE_SECTORS=33554432
+    ROOT_END=$((BOOT_END + ROOT_SIZE_SECTORS))
+
+    # SHRINKING: filesystem first, then partition
+    echo "  Checking filesystem..."
+    e2fsck -f -y "$ROOT_PART" 2>/dev/null || true
+
+    # Shrink filesystem to 15.5GB (leave room for partition overhead)
+    echo "  Shrinking filesystem to 15500M..."
+    resize2fs "$ROOT_PART" 15500M
+
+    # Delete and recreate partition 2 with 16GB size
+    echo "  Shrinking partition to 16GB..."
+    parted -s "$DEVICE" rm 2
+    parted -s "$DEVICE" mkpart primary ext4 $((BOOT_END + 1))s ${ROOT_END}s
+
+    # Refresh partition table
+    partprobe "$DEVICE"
+    sleep 2
+
+    # Expand filesystem to fill the partition exactly
+    echo "  Expanding filesystem to fill partition..."
+    e2fsck -f -y "$ROOT_PART" 2>/dev/null || true
+    resize2fs "$ROOT_PART"
+
+    echo -e "${GREEN}  Rootfs resized to 16GB${NC}"
+elif [ "$CURRENT_SIZE" -lt "$TARGET_BYTES" ]; then
+    echo -e "${YELLOW}  Rootfs is smaller than 16GB - expanding...${NC}"
+
+    # Get boot partition end in sectors
+    BOOT_END=$(parted -s "$DEVICE" unit s print | grep "^ 1" | awk '{print $3}' | tr -d 's')
+    ROOT_SIZE_SECTORS=33554432
+    ROOT_END=$((BOOT_END + ROOT_SIZE_SECTORS))
+
+    # EXPANDING: partition first, then filesystem
+    parted -s "$DEVICE" rm 2
+    parted -s "$DEVICE" mkpart primary ext4 $((BOOT_END + 1))s ${ROOT_END}s
+
+    partprobe "$DEVICE"
+    sleep 2
+
+    e2fsck -f -y "$ROOT_PART" 2>/dev/null || true
+    resize2fs "$ROOT_PART"
+
+    echo -e "${GREEN}  Rootfs expanded to 16GB${NC}"
+else
+    echo -e "${GREEN}  Rootfs already ~16GB${NC}"
+fi
+
+# ============================================================================
+# Pull image
+# ============================================================================
+echo
+echo -e "${BOLD}Partition table:${NC}"
+parted -s "$DEVICE" unit s print
+echo
+
+# Get the end of the last partition (partition 2 = rootfs)
+END_SECTOR=$(parted -s "$DEVICE" unit s print | grep "^ 2" | awk '{print $3}' | tr -d 's')
+
+if [ -z "$END_SECTOR" ]; then
+    echo -e "${RED}Error: Could not determine partition 2 end sector${NC}"
+    exit 1
+fi
+
+# Add a small buffer (1MB = 2048 sectors) for safety
+TOTAL_SECTORS=$((END_SECTOR + 2048))
+TOTAL_BYTES=$((TOTAL_SECTORS * 512))
+TOTAL_GB=$(echo "scale=2; $TOTAL_BYTES / 1073741824" | bc)
+
+echo -e "Image size: ${YELLOW}~${TOTAL_GB}GB${NC} (${TOTAL_SECTORS} sectors)"
+echo -e "Output: ${YELLOW}$OUTPUT${NC}"
+echo
+
+read -p "Proceed with image pull? [Y/n] " confirm
+if [[ "$confirm" =~ ^[Nn]$ ]]; then
     echo "Aborted."
     exit 1
 fi
 
-# Get device size for pv
-DEV_SIZE=$(blockdev --getsize64 "$SELECTED")
+echo
+echo -e "${GREEN}Pulling image...${NC}"
+echo
 
-echo ""
-echo -e "${GREEN}[1/4]${NC} Copying image from $SELECTED..."
-dd if="$SELECTED" bs=4M status=none | pv -s "$DEV_SIZE" > "$IMG_FILE"
-sync
-
-echo ""
-echo -e "${GREEN}[2/4]${NC} Re-enabling auto-expand for distribution..."
-# Mount the image and restore auto-expand service (may have been disabled during build)
-LOOP_DEV=$(losetup -f --show -P "$IMG_FILE")
-if [ -n "$LOOP_DEV" ]; then
-    TEMP_MOUNT=$(mktemp -d)
-    if mount "${LOOP_DEV}p2" "$TEMP_MOUNT" 2>/dev/null; then
-        # Re-enable the resize service if the service file exists
-        SERVICE_FILE="$TEMP_MOUNT/lib/systemd/system/rpi-resizerootfs.service"
-        SERVICE_LINK="$TEMP_MOUNT/etc/systemd/system/multi-user.target.wants/rpi-resizerootfs.service"
-        if [ -f "$SERVICE_FILE" ] && [ ! -L "$SERVICE_LINK" ]; then
-            mkdir -p "$(dirname "$SERVICE_LINK")"
-            ln -sf /lib/systemd/system/rpi-resizerootfs.service "$SERVICE_LINK"
-            echo -e "  ${GREEN}✓${NC} Auto-expand service re-enabled"
-        elif [ -L "$SERVICE_LINK" ]; then
-            echo -e "  ${GREEN}✓${NC} Auto-expand already enabled"
-        else
-            echo -e "  ${YELLOW}⚠${NC} Could not find resize service file"
-        fi
-        umount "$TEMP_MOUNT"
-    else
-        echo -e "  ${YELLOW}⚠${NC} Could not mount rootfs, skipping auto-expand fix"
-    fi
-    rmdir "$TEMP_MOUNT" 2>/dev/null || true
-    losetup -d "$LOOP_DEV"
+# Use pv if available for progress, otherwise fallback to dd status
+if command -v pv &> /dev/null; then
+    dd if="$DEVICE" bs=512 count=$TOTAL_SECTORS 2>/dev/null | \
+        pv -s $TOTAL_BYTES | \
+        zstd -T0 -3 > "$OUTPUT"
 else
-    echo -e "  ${YELLOW}⚠${NC} Could not create loop device, skipping auto-expand fix"
+    dd if="$DEVICE" bs=512 count=$TOTAL_SECTORS status=progress | \
+        zstd -T0 -3 > "$OUTPUT"
 fi
 
-echo ""
-echo -e "${GREEN}[3/4]${NC} Shrinking image..."
-if command -v pishrink.sh &> /dev/null; then
-    pishrink.sh "$IMG_FILE"
-elif [ -f "./pishrink.sh" ]; then
-    bash ./pishrink.sh "$IMG_FILE"
-elif [ -f "../pishrink.sh" ]; then
-    bash ../pishrink.sh "$IMG_FILE"
-else
-    echo -e "${YELLOW}pishrink.sh not found, skipping shrink step.${NC}"
-    echo "Download from: https://github.com/Drewsif/PiShrink"
-fi
+echo
+echo -e "${GREEN}Done!${NC} Image saved to: $OUTPUT"
+ls -lh "$OUTPUT"
 
-echo ""
-if [ "$SKIP_COMPRESS" = true ]; then
-    echo -e "${GREEN}[4/4]${NC} Skipping compression (.img output)"
-    FINAL_SIZE=$(du -h "$IMG_FILE" | awk '{print $1}')
-    OUTPUT="$IMG_FILE"
+# ============================================================================
+# Optional: Zip-wrap for GitHub releases
+# ============================================================================
+echo
+read -p "Create .zst.zip wrapper for GitHub? [y/N] " zip_confirm
+if [[ "$zip_confirm" =~ ^[Yy]$ ]]; then
+    ZIP_OUTPUT="${OUTPUT}.zip"
+    echo -e "${YELLOW}Creating zip wrapper (store mode, no compression)...${NC}"
+    zip -0 "$ZIP_OUTPUT" "$OUTPUT"
+    echo -e "${GREEN}Done!${NC} Upload this to GitHub Releases:"
+    ls -lh "$ZIP_OUTPUT"
+    echo
+    echo "Users can flash with:"
+    echo "  sudo ./rpi/flash-image.sh $ZIP_OUTPUT"
 else
-    echo -e "${GREEN}[4/4]${NC} Compressing with zstd..."
-    pv "$IMG_FILE" | zstd -19 -T0 -q > "$OUTPUT"
-    rm -f "$IMG_FILE"
-    FINAL_SIZE=$(du -h "$OUTPUT" | awk '{print $1}')
+    echo
+    echo "To verify:"
+    echo "  zstdcat $OUTPUT | fdisk -l /dev/stdin"
 fi
-
-echo ""
-echo -e "${GREEN}╔═══════════════════════════════════════════════════════════════╗${NC}"
-echo -e "${GREEN}║                    Image Complete!                            ║${NC}"
-echo -e "${GREEN}╚═══════════════════════════════════════════════════════════════╝${NC}"
-echo ""
-echo -e "Output: ${YELLOW}$OUTPUT${NC}"
-echo -e "Size:   ${YELLOW}$FINAL_SIZE${NC}"
-echo ""

rpi/remote-build-pi.sh

@@ -0,0 +1,144 @@
+#!/bin/bash
+#
+# Stegasoo Remote Pi Build Script
+# Waits for Pi to be reachable, then sets up Stegasoo
+#
+# Usage: ./remote-build-pi.sh [host] [user] [pass]
+#
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+# Pi connection settings (defaults)
+PI_HOST="${1:-stegasoo.local}"
+PI_USER="${2:-admin}"
+PI_PASS="${3:-stegasoo}"
+
+# Colors
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+CYAN='\033[0;36m'
+NC='\033[0m'
+
+# -----------------------------------------------------------------------------
+# Helper functions
+# -----------------------------------------------------------------------------
+
+wait_for_pi() {
+    local attempt=1
+    ssh-keygen -R "$PI_HOST" 2>/dev/null || true
+
+    echo "Waiting for $PI_USER@$PI_HOST..."
+    while ! sshpass -p "$PI_PASS" ssh -o ConnectTimeout=2 -o StrictHostKeyChecking=no -o BatchMode=no -o UserKnownHostsFile=/dev/null "$PI_USER@$PI_HOST" "exit" 2>/dev/null; do
+        printf "\rAttempt %d..." "$attempt"
+        ((attempt++))
+        sleep 2
+    done
+
+    printf "\r${GREEN}✓ Ready after %d attempts${NC}\n" "$attempt"
+    printf '\a'
+}
+
+run_on_pi() {
+    sshpass -p "$PI_PASS" ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null "$PI_USER@$PI_HOST" "$@"
+}
+
+run_on_pi_interactive() {
+    sshpass -p "$PI_PASS" ssh -t -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null "$PI_USER@$PI_HOST" "$@"
+}
+
+scp_to_pi() {
+    local src="$1"
+    local dst="$2"
+    sshpass -p "$PI_PASS" scp -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null "$src" "$PI_USER@$PI_HOST:$dst"
+}
+
+ssh_pi() {
+    ssh-keygen -R "$PI_HOST" 2>/dev/null || true
+    sshpass -p "$PI_PASS" ssh -t -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null "$PI_USER@$PI_HOST" "$@"
+}
+
+# -----------------------------------------------------------------------------
+# Main
+# -----------------------------------------------------------------------------
+
+echo -e "${CYAN}╔═══════════════════════════════════════════════════════════════╗${NC}"
+echo -e "${CYAN}║              Stegasoo Remote Pi Build                         ║${NC}"
+echo -e "${CYAN}╚═══════════════════════════════════════════════════════════════╝${NC}"
+echo ""
+echo -e "Host: ${YELLOW}$PI_HOST${NC}"
+echo -e "User: ${YELLOW}$PI_USER${NC}"
+echo ""
+
+# -----------------------------------------------------------------------------
+# Step 1: Wait for Pi to be ready
+# -----------------------------------------------------------------------------
+echo -e "${GREEN}[1/6]${NC} Waiting for Pi..."
+echo ""
+
+wait_for_pi
+
+# -----------------------------------------------------------------------------
+# Step 2: Install dependencies
+# -----------------------------------------------------------------------------
+echo ""
+echo -e "${GREEN}[2/6]${NC} Installing dependencies on Pi..."
+echo ""
+
+run_on_pi "sudo chown admin:admin /opt && sudo apt-get update && sudo apt-get install -y git zstd jq ca-certificates && sudo update-ca-certificates"
+
+# -----------------------------------------------------------------------------
+# Step 3: Clone repo
+# -----------------------------------------------------------------------------
+echo ""
+echo -e "${GREEN}[3/6]${NC} Cloning Stegasoo repo..."
+echo ""
+
+run_on_pi "cd /opt && rm -rf stegasoo && git clone https://github.com/adlee-was-taken/stegasoo.git stegasoo"
+
+# -----------------------------------------------------------------------------
+# Step 4: Copy pre-built tarball
+# -----------------------------------------------------------------------------
+echo ""
+echo -e "${GREEN}[4/6]${NC} Copying pre-built tarball to Pi..."
+echo ""
+
+TARBALL="$SCRIPT_DIR/stegasoo-rpi-venv-arm64.tar.zst"
+if [[ -f "$TARBALL" ]]; then
+    scp_to_pi "$TARBALL" "/opt/stegasoo/rpi/"
+    echo -e "  ${GREEN}✓${NC} Tarball copied"
+else
+    echo -e "  ${YELLOW}⚠${NC} Tarball not found at $TARBALL"
+    echo -e "  ${YELLOW}⚠${NC} Setup will build from source (takes longer)"
+fi
+
+# -----------------------------------------------------------------------------
+# Step 5: Run setup
+# -----------------------------------------------------------------------------
+echo ""
+echo -e "${GREEN}[5/6]${NC} Running setup.sh on Pi..."
+echo ""
+
+run_on_pi_interactive "cd /opt/stegasoo && ./rpi/setup.sh"
+
+# -----------------------------------------------------------------------------
+# Step 6: Test it works
+# -----------------------------------------------------------------------------
+echo ""
+echo -e "${GREEN}[6/6]${NC} Testing Stegasoo..."
+echo ""
+
+run_on_pi "sudo systemctl start stegasoo && sleep 2 && curl -sk https://localhost:5000 | head -5"
+
+echo ""
+echo -e "${GREEN}════════════════════════════════════════════════════════════════${NC}"
+echo -e "${GREEN}  Build complete! Pi is ready for testing.${NC}"
+echo -e "${GREEN}════════════════════════════════════════════════════════════════${NC}"
+echo ""
+echo -e "Access: ${YELLOW}https://$PI_HOST:5000${NC}"
+echo ""
+read -p "Press ENTER to SSH into Pi for manual testing..."
+
+ssh_pi

rpi/sanitize-for-image.sh

@@ -29,6 +29,10 @@ GRAY='\033[0;90m'
 BOLD='\033[1m'
 NC='\033[0m'
 
+# Source banner functions
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/banner.sh"
+
 # Show help
 show_help() {
     echo "Stegasoo Sanitize Script - Prepare Pi for SD Card Imaging"
@@ -70,21 +74,11 @@ if [ "$EUID" -ne 0 ]; then
 fi
 
 clear
-echo ""
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-echo -e "${GRAY} · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·${NC}"
-echo -e "\033[38;5;220m    ___  _____  ___    ___    _    ___    ___    ___\033[0m"
-echo -e "\033[38;5;220m   / __||_   _|| __|  / __|  /_\\\\  / __|  / _ \\\\  / _ \\\\\033[0m"
-echo -e "\033[38;5;220m   \\\\__ \\\\  | |  | _|  | (_ | / _ \\\\ \\\\__ \\\\ | (_) || (_) |\033[0m"
-echo -e "\033[38;5;220m   |___/  |_|  |___|  \\___|/_/ \\_\\\\|___/  \\\\___/  \\\\___/\033[0m"
-echo -e "${GRAY} · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·${NC}"
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
 if [ "$SOFT_RESET" = true ]; then
-    echo -e "\033[1;37m                  Soft Reset (Factory)\033[0m"
+    print_banner "Soft Reset (Factory)"
 else
-    echo -e "\033[1;37m                  Sanitize for Imaging\033[0m"
+    print_banner "Sanitize for Imaging"
 fi
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
 echo ""
 
 if [ "$SOFT_RESET" = true ]; then
@@ -270,49 +264,25 @@ if [ -n "$STEGASOO_DIR" ] && [ -d "$STEGASOO_DIR/venv" ]; then
         echo "  Venv broken or stegasoo not installed, rebuilding..."
         rm -rf "$STEGASOO_DIR/venv"
 
-        # Find Python 3.12 (prefer pyenv, fall back to system)
-        USER_HOME=$(eval echo "~$STEGASOO_USER")
-        PYENV_PYTHON="$USER_HOME/.pyenv/versions/3.12*/bin/python"
-        if compgen -G "$PYENV_PYTHON" > /dev/null 2>&1; then
-            PYTHON_BIN=$(ls $PYENV_PYTHON 2>/dev/null | head -1)
-            echo "  Using pyenv Python: $PYTHON_BIN"
-        elif command -v python3.12 &>/dev/null; then
-            PYTHON_BIN="python3.12"
-            echo "  Using system Python 3.12"
-        else
-            PYTHON_BIN="python3"
-            echo "  Warning: Python 3.12 not found, using $($PYTHON_BIN --version)"
-        fi
-
-        sudo -u "$STEGASOO_USER" "$PYTHON_BIN" -m venv "$STEGASOO_DIR/venv"
-        sudo -u "$STEGASOO_USER" "$STEGASOO_DIR/venv/bin/pip" install --quiet --upgrade pip setuptools wheel
-
-        # On ARM64, jpegio needs patching before install
-        ARCH=$(uname -m)
-        if [[ "$ARCH" == "aarch64" || "$ARCH" == "arm64" ]]; then
-            echo "  Building jpegio for ARM64 (this may take a minute)..."
-            # Install build deps
-            sudo -u "$STEGASOO_USER" "$STEGASOO_DIR/venv/bin/pip" install --quiet cython numpy
-            JPEGIO_DIR="/tmp/jpegio-build-$$"
-            rm -rf "$JPEGIO_DIR"
-            if git clone https://github.com/dwgoon/jpegio.git "$JPEGIO_DIR" 2>/dev/null; then
-                # Apply patch to remove -m64 flag
-                if [ -f "$STEGASOO_DIR/rpi/patches/jpegio/apply-patch.sh" ]; then
-                    bash "$STEGASOO_DIR/rpi/patches/jpegio/apply-patch.sh" "$JPEGIO_DIR"
-                else
-                    sed -i "s/cargs.append('-m64')/pass  # ARM64 fix/g" "$JPEGIO_DIR/setup.py"
-                fi
-                # Change ownership so user can build
-                chown -R "$STEGASOO_USER:$STEGASOO_USER" "$JPEGIO_DIR"
-                sudo -u "$STEGASOO_USER" "$STEGASOO_DIR/venv/bin/pip" install "$JPEGIO_DIR"
-                rm -rf "$JPEGIO_DIR"
-            else
-                echo "  Warning: Failed to clone jpegio, DCT mode may not work"
+        # Find system Python 3.11+ (no pyenv needed)
+        PYTHON_BIN=""
+        for py in python3.14 python3.13 python3.12 python3.11 python3; do
+            if command -v "$py" &>/dev/null; then
+                PYTHON_BIN=$(command -v "$py")
+                break
             fi
-        fi
+        done
 
-        sudo -u "$STEGASOO_USER" "$STEGASOO_DIR/venv/bin/pip" install --quiet -e "$STEGASOO_DIR[web]"
-        echo "  Venv rebuilt and stegasoo installed"
+        if [ -z "$PYTHON_BIN" ]; then
+            echo "  Error: Python 3.11+ not found"
+            VALIDATION_ERRORS=$((VALIDATION_ERRORS + 1))
+        else
+            echo "  Using: $PYTHON_BIN ($($PYTHON_BIN --version 2>&1))"
+            sudo -u "$STEGASOO_USER" "$PYTHON_BIN" -m venv "$STEGASOO_DIR/venv"
+            sudo -u "$STEGASOO_USER" "$STEGASOO_DIR/venv/bin/pip" install --quiet --upgrade pip setuptools wheel
+            sudo -u "$STEGASOO_USER" "$STEGASOO_DIR/venv/bin/pip" install --quiet -e "$STEGASOO_DIR[web]"
+            echo "  Venv rebuilt and stegasoo installed"
+        fi
     else
         echo "  Venv OK"
     fi

rpi/setup.sh

@@ -4,14 +4,14 @@
 # Tested on: Raspberry Pi 4/5 with Raspberry Pi OS (64-bit)
 #
 # Usage:
-#   curl -sSL https://raw.githubusercontent.com/adlee-was-taken/stegasoo/4.1/rpi/setup.sh | bash
+#   curl -sSL https://raw.githubusercontent.com/adlee-was-taken/stegasoo/4.2/rpi/setup.sh | bash
 #   # or
-#   wget -qO- https://raw.githubusercontent.com/adlee-was-taken/stegasoo/4.1/rpi/setup.sh | bash
+#   wget -qO- https://raw.githubusercontent.com/adlee-was-taken/stegasoo/4.2/rpi/setup.sh | bash
 #
 # What this script does:
 #   1. Installs system dependencies
-#   2. Installs Python 3.12 via pyenv (Pi OS ships with 3.13 which is incompatible)
-#   3. Patches and builds jpegio for ARM
+#   2. Verifies Python 3.11+ (uses system Python)
+#   3. Installs jpeglib for DCT steganography (Python 3.11-3.14 compatible)
 #   4. Installs Stegasoo with web UI
 #   5. Creates systemd service for auto-start
 #   6. Enables the service
@@ -29,6 +29,33 @@ GRAY='\033[0;90m'
 BOLD='\033[1m'
 NC='\033[0m' # No Color
 
+# Source banner.sh if available (for local runs), otherwise define inline
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" 2>/dev/null && pwd)"
+if [ -f "$SCRIPT_DIR/banner.sh" ]; then
+    source "$SCRIPT_DIR/banner.sh"
+else
+    # Inline banner functions for curl-pipe execution
+    print_gradient_line() {
+        echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
+    }
+    print_banner() {
+        local subtitle="$1"
+        echo ""
+        print_gradient_line
+        echo -e "\033[0;90m · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·\033[0m"
+        echo -e "\033[38;5;220m    ___  _____  ___    ___    _    ___    ___    ___\033[0m"
+        echo -e "\033[38;5;220m   / __||_   _|| __|  / __|  /_\\  / __|  / _ \\  / _ \\\\\033[0m"
+        echo -e "\033[38;5;220m   \\__ \\  | |  | _|  | (_ | / _ \\ \\__ \\ | (_) || (_) |\033[0m"
+        echo -e "\033[38;5;220m   |___/  |_|  |___|  \\___//_/ \\_\\|___/  \\___/  \\___/\033[0m"
+        echo -e "\033[0;90m · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·\033[0m"
+        print_gradient_line
+        if [ -n "$subtitle" ]; then
+            echo -e "\033[1;37m                    ${subtitle}\033[0m"
+            print_gradient_line
+        fi
+    }
+fi
+
 # Show help
 show_help() {
     echo "Stegasoo Raspberry Pi Setup Script"
@@ -48,9 +75,8 @@ show_help() {
     echo ""
     echo "  Available variables:"
     echo "    INSTALL_DIR       Install location (default: /opt/stegasoo)"
-    echo "    PYTHON_VERSION    Python version (default: 3.12)"
     echo "    STEGASOO_REPO     Git repo URL"
-    echo "    STEGASOO_BRANCH   Git branch (default: 4.1)"
+    echo "    STEGASOO_BRANCH   Git branch (default: 4.2)"
     echo ""
     echo "  Example:"
     echo "    export INSTALL_DIR=\"/home/pi/stegasoo\""
@@ -68,10 +94,8 @@ done
 
 # Default configuration
 INSTALL_DIR="${INSTALL_DIR:-/opt/stegasoo}"
-PYTHON_VERSION="${PYTHON_VERSION:-3.12}"
 STEGASOO_REPO="${STEGASOO_REPO:-https://github.com/adlee-was-taken/stegasoo.git}"
-STEGASOO_BRANCH="${STEGASOO_BRANCH:-4.1}"
-JPEGIO_REPO="https://github.com/dwgoon/jpegio.git"
+STEGASOO_BRANCH="${STEGASOO_BRANCH:-4.2}"
 
 # Load config files (system, then user - user overrides system)
 for config_file in "/etc/stegasoo.conf" "$HOME/.config/stegasoo/stegasoo.conf"; do
@@ -82,20 +106,10 @@ for config_file in "/etc/stegasoo.conf" "$HOME/.config/stegasoo/stegasoo.conf";
 done
 
 clear
-echo ""
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-echo -e "${GRAY} · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·${NC}"
-echo -e "\033[38;5;220m    ___  _____  ___    ___    _    ___    ___    ___\033[0m"
-echo -e "\033[38;5;220m   / __||_   _|| __|  / __|  /_\\\\  / __|  / _ \\\\  / _ \\\\\033[0m"
-echo -e "\033[38;5;220m   \\\\__ \\\\  | |  | _|  | (_ | / _ \\\\ \\\\__ \\\\ | (_) || (_) |\033[0m"
-echo -e "\033[38;5;220m   |___/  |_|  |___|  \\___|/_/ \\_\\\\|___/  \\\\___/  \\\\___/\033[0m"
-echo -e "${GRAY} · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·${NC}"
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-echo -e "\033[1;37m                   Raspberry Pi Setup\033[0m"
-echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
+print_banner "Raspberry Pi Setup"
 echo ""
 echo "  This will install Stegasoo with full DCT support"
-echo "  Estimated time: ~2 minutes (pre-built) or 15-20 min (from source)"
+echo "  Estimated time: ~2 minutes (pre-built) or 5-10 min (from source)"
 echo ""
 
 # Check if running on ARM
@@ -106,6 +120,63 @@ if [[ "$ARCH" != "aarch64" && "$ARCH" != "arm64" ]]; then
     exit 1
 fi
 
+# =============================================================================
+# Python Version Check
+# =============================================================================
+echo -e "${GREEN}Checking Python version...${NC}"
+
+# Find system Python
+SYSTEM_PYTHON=""
+for py in python3.14 python3.13 python3.12 python3.11 python3; do
+    if command -v "$py" &>/dev/null; then
+        SYSTEM_PYTHON=$(command -v "$py")
+        break
+    fi
+done
+
+if [ -z "$SYSTEM_PYTHON" ]; then
+    echo -e "${RED}Error: Python 3 not found.${NC}"
+    echo "Please install Python 3.11 or later:"
+    echo "  sudo apt-get install python3"
+    exit 1
+fi
+
+# Get version numbers
+PY_VERSION=$("$SYSTEM_PYTHON" -c 'import sys; print(f"{sys.version_info.major}.{sys.version_info.minor}")')
+PY_MAJOR=$("$SYSTEM_PYTHON" -c 'import sys; print(sys.version_info.major)')
+PY_MINOR=$("$SYSTEM_PYTHON" -c 'import sys; print(sys.version_info.minor)')
+
+echo "  Found: $SYSTEM_PYTHON (Python $PY_VERSION)"
+
+# Check version range (3.11 <= version <= 3.14)
+if [ "$PY_MAJOR" -ne 3 ]; then
+    echo -e "${RED}Error: Python 3 required, found Python $PY_MAJOR${NC}"
+    exit 1
+fi
+
+if [ "$PY_MINOR" -lt 11 ]; then
+    echo -e "${RED}Error: Python 3.11+ required, found Python $PY_VERSION${NC}"
+    echo ""
+    echo "Raspberry Pi OS Bookworm ships with Python 3.11."
+    echo "Raspberry Pi OS Trixie ships with Python 3.13."
+    echo ""
+    echo "Please upgrade your Raspberry Pi OS or install Python 3.11+."
+    exit 1
+fi
+
+if [ "$PY_MINOR" -gt 14 ]; then
+    echo -e "${YELLOW}Warning: Python $PY_VERSION detected.${NC}"
+    echo "Stegasoo is tested with Python 3.11-3.14."
+    echo "Newer versions may work but are not officially supported."
+    read -p "Continue anyway? [y/N] " -n 1 -r
+    echo
+    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
+        exit 1
+    fi
+fi
+
+echo -e "  ${GREEN}✓${NC} Python $PY_VERSION supported"
+
 # Check available memory
 TOTAL_MEM=$(free -m | awk '/^Mem:/{print $2}')
 if [ "$TOTAL_MEM" -lt 2000 ]; then
@@ -119,8 +190,11 @@ if [ "$TOTAL_MEM" -lt 2000 ]; then
     fi
 fi
 
-# Create /opt/stegasoo with proper permissions
-echo -e "${GREEN}[1/12]${NC} Setting up install directory..."
+# =============================================================================
+# Installation
+# =============================================================================
+
+echo -e "${GREEN}[1/9]${NC} Setting up install directory..."
 if [ ! -d "$INSTALL_DIR" ]; then
     sudo mkdir -p "$INSTALL_DIR"
     sudo chown "$USER:$USER" "$INSTALL_DIR"
@@ -131,7 +205,7 @@ else
     echo "  $INSTALL_DIR exists, updated ownership"
 fi
 
-echo -e "${GREEN}[2/12]${NC} Installing system dependencies..."
+echo -e "${GREEN}[2/9]${NC} Installing system dependencies..."
 sudo apt-get update
 sudo apt-get install -y \
     build-essential \
@@ -153,9 +227,11 @@ sudo apt-get install -y \
     libzbar0 \
     libjpeg-dev \
     python3-dev \
+    python3-venv \
+    python3-pip \
     btop
 
-echo -e "${GREEN}[3/12]${NC} Installing gum (TUI toolkit)..."
+echo -e "${GREEN}[3/9]${NC} Installing gum (TUI toolkit)..."
 # Add Charm repo for gum
 if ! command -v gum &>/dev/null; then
     sudo mkdir -p /etc/apt/keyrings
@@ -167,7 +243,21 @@ else
     echo "  gum already installed"
 fi
 
-echo -e "${GREEN}[4/12]${NC} Cloning Stegasoo..."
+# Install mkcert for browser-trusted certificates (no warning screen!)
+echo "  Installing mkcert for trusted HTTPS certificates..."
+if ! command -v mkcert &>/dev/null; then
+    sudo apt-get install -y libnss3-tools
+    # Download mkcert for ARM64
+    sudo curl -sL "https://github.com/FiloSottile/mkcert/releases/download/v1.4.4/mkcert-v1.4.4-linux-arm64" -o /usr/local/bin/mkcert
+    sudo chmod +x /usr/local/bin/mkcert
+    # Install local CA (makes certs trusted on this Pi)
+    mkcert -install 2>/dev/null || true
+    echo "  mkcert installed"
+else
+    echo "  mkcert already installed"
+fi
+
+echo -e "${GREEN}[4/9]${NC} Cloning Stegasoo..."
 
 # Clone Stegasoo first (needed to check for pre-built tarball)
 if [ -d "$INSTALL_DIR/.git" ]; then
@@ -181,17 +271,16 @@ else
     cd "$INSTALL_DIR"
 fi
 
-# Pre-built environment tarball (skips 20+ min compile time)
-# Includes both pyenv Python 3.12 AND venv with all dependencies
-PREBUILT_TARBALL="$INSTALL_DIR/rpi/stegasoo-pi-arm64.tar.zst"
-PREBUILT_URL="${PREBUILT_URL:-https://github.com/adlee-was-taken/stegasoo/releases/download/v4.1.3/stegasoo-pi-arm64.tar.zst}"
+# Pre-built venv tarball (skips pip compile time)
+PREBUILT_TARBALL="$INSTALL_DIR/rpi/stegasoo-rpi-venv-arm64.tar.zst"
+PREBUILT_URL="${PREBUILT_URL:-https://github.com/adlee-was-taken/stegasoo/releases/download/v4.2.0/stegasoo-rpi-venv-arm64.tar.zst}"
 USE_PREBUILT=true
 
 # Use local tarball if present, otherwise will download
 if [ -f "$PREBUILT_TARBALL" ]; then
-    echo -e "${GREEN}Found local pre-built environment - fast install mode${NC}"
+    echo -e "${GREEN}Found local pre-built venv - fast install mode${NC}"
 else
-    echo -e "${GREEN}Will download pre-built environment - fast install mode${NC}"
+    echo -e "${GREEN}Will download pre-built venv - fast install mode${NC}"
 fi
 
 # Allow --no-prebuilt flag to force from-source build
@@ -200,44 +289,30 @@ if [[ " $* " =~ " --no-prebuilt " ]] || [[ " $* " =~ " --from-source " ]]; then
     echo -e "${YELLOW}Building from source (--no-prebuilt specified)${NC}"
 fi
 
-# Fast path: use pre-built environment if available
+echo -e "${GREEN}[5/9]${NC} Setting up Python environment..."
+
 if [ "$USE_PREBUILT" = true ]; then
-    echo -e "${GREEN}[5/8]${NC} Installing pre-built Python environment..."
+    # Fast path: use pre-built venv
 
     # Download if local file doesn't exist
     if [ ! -f "$PREBUILT_TARBALL" ]; then
-        echo "  Downloading pre-built environment (~50MB)..."
+        echo "  Downloading pre-built venv (~50MB)..."
         curl -L -o "$PREBUILT_TARBALL" "$PREBUILT_URL"
     fi
 
-    # Extract pre-built environment (includes pyenv Python + venv)
-    echo "  Extracting pre-built environment..."
-    zstd -d "$PREBUILT_TARBALL" --stdout | tar -xf - -C "$HOME"
+    # Extract pre-built venv
+    echo "  Extracting pre-built venv..."
+    zstd -d "$PREBUILT_TARBALL" --stdout | tar -xf - -C "$INSTALL_DIR"
 
-    # Setup pyenv in current shell
-    export PYENV_ROOT="$HOME/.pyenv"
-    export PATH="$PYENV_ROOT/bin:$PATH"
-    eval "$(pyenv init -)"
-    pyenv global $PYTHON_VERSION
+    # Fix venv Python symlinks to point to system Python
+    echo "  Updating venv to use system Python..."
+    rm -f "$INSTALL_DIR/venv/bin/python" "$INSTALL_DIR/venv/bin/python3"
+    ln -s "$SYSTEM_PYTHON" "$INSTALL_DIR/venv/bin/python"
+    ln -s "$SYSTEM_PYTHON" "$INSTALL_DIR/venv/bin/python3"
 
-    # Add to .bashrc if not already there
-    if ! grep -q 'PYENV_ROOT' ~/.bashrc; then
-        echo '' >> ~/.bashrc
-        echo '# pyenv' >> ~/.bashrc
-        echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bashrc
-        echo '[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc
-        echo 'eval "$(pyenv init - bash)"' >> ~/.bashrc
-    fi
-
-    # Verify Python
-    INSTALLED_PY=$(python --version 2>&1 | cut -d' ' -f2 | cut -d'.' -f1,2)
-    echo -e "  ${GREEN}✓${NC} Python: $INSTALLED_PY"
-
-    # Extract venv to install dir
-    echo -e "${GREEN}[6/8]${NC} Setting up virtual environment..."
-    if [ -f "$HOME/stegasoo-venv.tar.zst" ]; then
-        zstd -d "$HOME/stegasoo-venv.tar.zst" --stdout | tar -xf - -C "$INSTALL_DIR"
-        rm "$HOME/stegasoo-venv.tar.zst"
+    # Update pip shebang if needed
+    if [ -f "$INSTALL_DIR/venv/bin/pip" ]; then
+        sed -i "1s|^#!.*|#!$INSTALL_DIR/venv/bin/python|" "$INSTALL_DIR/venv/bin/pip" 2>/dev/null || true
     fi
 
     # Activate and verify
@@ -246,105 +321,87 @@ if [ "$USE_PREBUILT" = true ]; then
     echo -e "  ${GREEN}✓${NC} venv Python: $VENV_PY"
 
     # Install stegasoo package in editable mode (quick, no compile)
-    echo -e "${GREEN}[7/8]${NC} Installing Stegasoo package..."
+    echo "  Installing Stegasoo package..."
     pip install -e "." --quiet
-
-    # Adjust step numbers for rest of script
-    STEP_OFFSET=-4
 else
-    echo -e "${GREEN}[5/12]${NC} Installing pyenv and Python $PYTHON_VERSION..."
+    # Build from source
+    echo -e "  ${YELLOW}Building from source (this takes 5-10 minutes)${NC}"
 
-    # Install pyenv if not present
-    if [ ! -d "$HOME/.pyenv" ]; then
-        curl https://pyenv.run | bash
-
-        # Add pyenv to current shell
-        export PYENV_ROOT="$HOME/.pyenv"
-        export PATH="$PYENV_ROOT/bin:$PATH"
-        eval "$(pyenv init -)"
-
-        # Add to .bashrc if not already there
-        if ! grep -q 'PYENV_ROOT' ~/.bashrc; then
-            echo '' >> ~/.bashrc
-            echo '# pyenv' >> ~/.bashrc
-            echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bashrc
-            echo '[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc
-            echo 'eval "$(pyenv init - bash)"' >> ~/.bashrc
-        fi
-    else
-        echo "  pyenv already installed"
-        export PYENV_ROOT="$HOME/.pyenv"
-        export PATH="$PYENV_ROOT/bin:$PATH"
-        eval "$(pyenv init -)"
+    # Create venv with system Python
+    if [ ! -d "$INSTALL_DIR/venv" ]; then
+        "$SYSTEM_PYTHON" -m venv "$INSTALL_DIR/venv"
     fi
-
-    # Install Python 3.12 if not present
-    if ! pyenv versions | grep -q "$PYTHON_VERSION"; then
-        echo "  Building Python $PYTHON_VERSION (this takes ~10 minutes)..."
-        pyenv install $PYTHON_VERSION
-    else
-        echo "  Python $PYTHON_VERSION already installed"
-    fi
-    pyenv global $PYTHON_VERSION
-
-    # Verify Python version
-    INSTALLED_PY=$(python --version 2>&1 | cut -d' ' -f2 | cut -d'.' -f1,2)
-    if [ "$INSTALLED_PY" != "$PYTHON_VERSION" ]; then
-        echo -e "${RED}Error: Python $PYTHON_VERSION not active. Got: $INSTALLED_PY${NC}"
-        exit 1
-    fi
-    echo -e "${GREEN}[6/12]${NC} Creating Python virtual environment..."
-    echo -e "  ${YELLOW}Note: No pre-built venv found. Building from source (20+ min)${NC}"
-    echo -e "  ${YELLOW}To speed up future installs, add stegasoo-venv-pi-arm64.tar.gz to rpi/${NC}"
-
-    # Create venv with pyenv Python (not system Python)
-    # Use pyenv which to get actual path (handles 3.12 -> 3.12.12 mapping)
-    PYENV_PYTHON=$(pyenv which python)
-    echo "  Using Python: $PYENV_PYTHON"
-    if [ ! -d "venv" ]; then
-        "$PYENV_PYTHON" -m venv venv
-    fi
-    source venv/bin/activate
+    source "$INSTALL_DIR/venv/bin/activate"
 
     # Verify we're using the right Python
     VENV_PY=$(python --version 2>&1 | cut -d' ' -f2 | cut -d'.' -f1,2)
     echo "  venv Python: $VENV_PY"
 
-    echo -e "${GREEN}[7/12]${NC} Building jpegio for ARM..."
+    # Upgrade pip and install build tools
+    pip install --upgrade pip setuptools wheel
 
-    # Clone jpegio
-    JPEGIO_DIR="/tmp/jpegio-build"
-    rm -rf "$JPEGIO_DIR"
-    git clone "$JPEGIO_REPO" "$JPEGIO_DIR"
+    # Install jpeglib (no ARM64 wheel, PyPI tarball missing headers - use GitHub)
+    echo "  Installing jpeglib for ARM64..."
+    JPEGLIB_WORKDIR=$(mktemp -d)
+    cd "$JPEGLIB_WORKDIR"
 
-    # Apply ARM64 patch
-    if [ -f "$INSTALL_DIR/rpi/patches/jpegio/apply-patch.sh" ]; then
-        bash "$INSTALL_DIR/rpi/patches/jpegio/apply-patch.sh" "$JPEGIO_DIR"
-    else
-        echo "  Applying inline ARM64 patch..."
-        sed -i "s/cargs.append('-m64')/pass  # ARM64 fix/g" "$JPEGIO_DIR/setup.py"
-    fi
+    # Clone from GitHub (PyPI source tarball is missing .h files)
+    echo "    Cloning jpeglib from GitHub..."
+    git clone --depth 1 --branch 1.0.2 https://github.com/martinbenes1996/jpeglib.git
+    cd jpeglib
+    CJPEGLIB="src/jpeglib/cjpeglib"
 
-    cd "$JPEGIO_DIR"
+    # Fix broken include paths in setup.py (uses jpeglib/ but files are in src/jpeglib/)
+    ln -s src/jpeglib jpeglib
 
-    # Build jpegio into venv
-    pip install --upgrade pip setuptools wheel cython numpy
+    # Download libjpeg headers (not included in repo either)
+    # Each version needs EXACT matching headers (APIs differ between versions)
+    echo "    Downloading libjpeg headers (all versions)..."
+
+    # Download each version separately (APIs are incompatible between versions)
+    for v in 6b 7 8 8a 8b 8c 8d 9 9a 9b 9c 9d 9e 9f; do
+        echo "      libjpeg $v..."
+        curl -sL "https://www.ijg.org/files/jpegsrc.v${v}.tar.gz" | tar -xzf -
+        cp jpeg-${v}/*.h "$CJPEGLIB/$v/" 2>/dev/null || cp jpeg-${v//.}/*.h "$CJPEGLIB/$v/" 2>/dev/null || true
+    done
+
+    # Skip turbo/mozjpeg - they need cmake-generated headers
+    # Only remove dict entries (lines 49-59), keep if blocks (they're safe when is_turbo=False)
+    echo "    Patching setup.py to skip turbo/mozjpeg (need cmake)..."
+    python3 << 'PYPATCH'
+with open('setup.py', 'r') as f:
+    lines = f.readlines()
+filtered = []
+for line in lines:
+    # Only skip dict entries like "'turbo120': ..." or "'mozjpeg101': ..."
+    stripped = line.strip()
+    if stripped.startswith("'turbo") and ':' in stripped:
+        continue
+    if stripped.startswith("'mozjpeg") and ':' in stripped:
+        continue
+    if stripped.startswith("# 'turbo"):  # commented turbo line
+        continue
+    filtered.append(line)
+with open('setup.py', 'w') as f:
+    f.writelines(filtered)
+PYPATCH
+
+    # Build and install
+    echo "    Building jpeglib (this takes a few minutes)..."
     pip install .
-
     cd "$INSTALL_DIR"
-    rm -rf "$JPEGIO_DIR"
+    rm -rf "$JPEGLIB_WORKDIR"
 
-    echo -e "${GREEN}[8/12]${NC} Installing Stegasoo..."
-
-    # Install dependencies (jpegio already in venv, won't re-download)
+    # Install remaining dependencies
+    echo "  Installing remaining dependencies..."
     pip install -e ".[web]"
-
-    STEP_OFFSET=0
 fi
 
-echo -e "${GREEN}[9/12]${NC} Creating systemd service..."
+echo -e "  ${GREEN}✓${NC} Stegasoo installed"
 
-# Create systemd service file
+echo -e "${GREEN}[6/9]${NC} Creating systemd services..."
+
+# Create systemd service file for Web UI
 sudo tee /etc/systemd/system/stegasoo.service > /dev/null <<EOF
 [Unit]
 Description=Stegasoo Web UI
@@ -366,12 +423,53 @@ RestartSec=5
 WantedBy=multi-user.target
 EOF
 
-echo -e "${GREEN}[10/12]${NC} Enabling service..."
+# Create systemd service file for REST API (optional)
+sudo tee /etc/systemd/system/stegasoo-api.service > /dev/null <<EOF
+[Unit]
+Description=Stegasoo REST API
+After=network.target
+
+[Service]
+Type=simple
+User=$USER
+WorkingDirectory=$INSTALL_DIR/frontends/api
+Environment="PATH=$INSTALL_DIR/venv/bin:/usr/bin"
+Environment="PYTHONPATH=$INSTALL_DIR/src"
+ExecStart=$INSTALL_DIR/venv/bin/uvicorn main:app --host 0.0.0.0 --port 8000
+Restart=on-failure
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+echo -e "${GREEN}[7/9]${NC} Enabling services..."
 
 sudo systemctl daemon-reload
 sudo systemctl enable stegasoo.service
 
-echo -e "${GREEN}[11/12]${NC} Setting up user environment..."
+# Prompt for REST API service (optional, with security warning)
+echo ""
+echo -e "${CYAN}Would you like to enable the REST API service? (port 8000)${NC}"
+echo ""
+echo -e "  ${RED}⚠ WARNING: The REST API has NO AUTHENTICATION${NC}"
+echo "  Anyone on your network can use it to encode/decode messages."
+echo "  Only enable if you understand the security implications."
+echo ""
+echo "  The Web UI (port 5000) has authentication and works independently."
+echo ""
+read -p "Enable REST API (no auth)? [y/N]: " ENABLE_API
+if [[ "$ENABLE_API" =~ ^[Yy]$ ]]; then
+    sudo systemctl enable stegasoo-api.service
+    STEGASOO_API_ENABLED=true
+    echo -e "  ${YELLOW}⚠${NC} REST API enabled on port 8000 ${RED}(no authentication)${NC}"
+else
+    STEGASOO_API_ENABLED=false
+    echo -e "  ${GREEN}✓${NC} REST API not enabled (recommended)"
+    echo "    Can enable later with: sudo systemctl enable --now stegasoo-api"
+fi
+
+echo -e "${GREEN}[8/9]${NC} Setting up user environment..."
 
 # Add stegasoo venv and rpi scripts to PATH for all users
 sudo tee /etc/profile.d/stegasoo-path.sh > /dev/null <<'PATHEOF'
@@ -397,7 +495,15 @@ if [ -f "$INSTALL_DIR/rpi/skel/.bashrc" ]; then
     fi
 fi
 
-echo -e "${GREEN}[12/12]${NC} Setting up login banner..."
+# Install man page
+if [ -f "$INSTALL_DIR/docs/stegasoo.1" ]; then
+    sudo mkdir -p /usr/local/share/man/man1
+    sudo cp "$INSTALL_DIR/docs/stegasoo.1" /usr/local/share/man/man1/
+    sudo mandb -q 2>/dev/null || true
+    echo "  Installed man page (man stegasoo)"
+fi
+
+echo -e "${GREEN}[9/9]${NC} Setting up login banner..."
 
 # Create dynamic MOTD script
 sudo tee /etc/profile.d/stegasoo-motd.sh > /dev/null <<'MOTDEOF'
@@ -424,19 +530,35 @@ if systemctl is-active --quiet stegasoo 2>/dev/null; then
     echo -e "\033[38;5;220m   |___/  |_|  |___|  \\___//_/ \\_\\|___/  \\___/  \\___/\033[0m"
     echo -e "\033[0;90m · .  · .  *  · .  *  · .  *  · .  *  · .  *  · .  ·\033[0m"
     echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
-    echo -e " \033[0;32m●\033[0m Stegasoo is running"
-    echo -e "   \033[0;33m$STEGASOO_URL\033[0m"
     # Show CPU stats if overclocked (read configured freq, not current idle freq)
     CONFIG_FILE=""
     if [ -f /boot/firmware/config.txt ]; then CONFIG_FILE="/boot/firmware/config.txt"
     elif [ -f /boot/config.txt ]; then CONFIG_FILE="/boot/config.txt"; fi
+    CPU_MHZ=""
+    CPU_TEMP=""
     if [ -n "$CONFIG_FILE" ] && grep -qE "^arm_freq=" "$CONFIG_FILE" 2>/dev/null; then
         CPU_MHZ=$(grep "^arm_freq=" "$CONFIG_FILE" | cut -d= -f2)
         CPU_TEMP=$(vcgencmd measure_temp 2>/dev/null | cut -d= -f2)
-        if [ -n "$CPU_MHZ" ] && [ -n "$CPU_TEMP" ]; then
-            echo -e "   \033[0;35m⚡\033[0m ${CPU_MHZ} MHz  \033[0;35m🌡\033[0m ${CPU_TEMP}"
-        fi
     fi
+    # Compact two-column layout
+    echo -e " 🚀 Stegasoo running     🌐 \033[0;33m$STEGASOO_URL\033[0m"
+    if [ -n "$CPU_MHZ" ] && [ -n "$CPU_TEMP" ]; then
+        # Temp emoji: ice<50, cool 50-70, fire>70
+        TEMP_NUM=$(echo "$CPU_TEMP" | grep -oE "[0-9]+" | head -1)
+        if [ -n "$TEMP_NUM" ]; then
+            if [ "$TEMP_NUM" -ge 70 ]; then
+                TEMP_EMOJI="🔥"
+            elif [ "$TEMP_NUM" -ge 50 ]; then
+                TEMP_EMOJI="😎"
+            else
+                TEMP_EMOJI="🧊"
+            fi
+        else
+            TEMP_EMOJI="🌡"
+        fi
+        echo -e " \033[0;35m⚡\033[0m ${CPU_MHZ} MHz             ${TEMP_EMOJI} ${CPU_TEMP}"
+    fi
+    echo -e "\033[38;5;93m══════════════\033[38;5;99m══════════════\033[38;5;105m══════════════\033[38;5;117m══════════════\033[0m"
     echo ""
 else
     echo ""
@@ -448,6 +570,10 @@ MOTDEOF
 sudo chmod 644 /etc/profile.d/stegasoo-motd.sh
 echo "  Created login banner"
 
+# Shorten the default Debian MOTD boilerplate
+echo "Debian GNU/Linux · License: /usr/share/doc/*/copyright" | sudo tee /etc/motd > /dev/null
+echo "  Shortened system MOTD"
+
 echo ""
 echo -e "${BOLD}Installation Complete!${NC}"
 echo -e "${BLUE}-------------------------------------------------------${NC}"
@@ -506,9 +632,15 @@ echo ""
 read -p "Generate a private channel key? [y/N] " -n 1 -r
 echo
 if [[ $REPLY =~ ^[Yy]$ ]]; then
-    # Generate channel key using the CLI
-    CHANNEL_KEY=$($INSTALL_DIR/venv/bin/python -c "from stegasoo.channel import generate_channel_key; print(generate_channel_key())")
+    # Generate channel key and save encrypted to config
+    CHANNEL_KEY=$($INSTALL_DIR/venv/bin/python -c "
+from stegasoo.channel import generate_channel_key, set_channel_key
+key = generate_channel_key()
+set_channel_key(key, 'user')  # Saves encrypted to ~/.stegasoo/channel.key
+print(key)
+")
     echo -e "  ${GREEN}✓${NC} Channel key generated: ${YELLOW}$CHANNEL_KEY${NC}"
+    echo -e "  ${GREEN}✓${NC} Key saved (encrypted) to ~/.stegasoo/channel.key"
     echo ""
     echo -e "  ${RED}IMPORTANT: Save this key!${NC} You'll need to share it with anyone"
     echo "  who should be able to decode your images."
@@ -556,19 +688,40 @@ if [ "$ENABLE_HTTPS" = "true" ]; then
     LOCAL_IP=$(hostname -I | awk '{print $1}')
     PI_HOSTNAME=$(hostname)
 
-    # Generate cert with SANs for IP, hostname, and localhost
-    openssl req -x509 -newkey rsa:2048 \
-      -keyout "$CERT_DIR/server.key" \
-      -out "$CERT_DIR/server.crt" \
-      -days 365 -nodes \
-      -subj "/O=Stegasoo/CN=$PI_HOSTNAME" \
-      -addext "subjectAltName=DNS:$PI_HOSTNAME,DNS:$PI_HOSTNAME.local,DNS:localhost,IP:$LOCAL_IP,IP:127.0.0.1" \
-      2>/dev/null
+    # Try mkcert first (creates browser-trusted certs - no warning screen!)
+    if command -v mkcert &> /dev/null; then
+        echo "  Using mkcert for browser-trusted certificates..."
+        cd "$CERT_DIR"
+        mkcert -key-file server.key -cert-file server.crt \
+            "$PI_HOSTNAME" "$PI_HOSTNAME.local" localhost "$LOCAL_IP" 127.0.0.1 ::1
+
+        # Copy CA to web-accessible location for easy device setup
+        CA_ROOT=$(mkcert -CAROOT)
+        CA_DIR="$INSTALL_DIR/frontends/web/static/ca"
+        mkdir -p "$CA_DIR"
+        cp "$CA_ROOT/rootCA.pem" "$CA_DIR/"
+
+        echo -e "  ${GREEN}✓${NC} Trusted certificates generated with mkcert"
+        echo -e "  ${CYAN}Tip:${NC} New devices can get the CA from: http://$PI_HOSTNAME.local/static/ca/rootCA.pem"
+    else
+        # Fallback to self-signed (shows browser warning)
+        echo "  Using self-signed certificate (browser will show warning)"
+        echo "  Tip: Install mkcert for trusted certs without warnings"
+
+        openssl req -x509 -newkey rsa:2048 \
+          -keyout "$CERT_DIR/server.key" \
+          -out "$CERT_DIR/server.crt" \
+          -days 365 -nodes \
+          -subj "/O=Stegasoo/CN=$PI_HOSTNAME" \
+          -addext "subjectAltName=DNS:$PI_HOSTNAME,DNS:$PI_HOSTNAME.local,DNS:localhost,IP:$LOCAL_IP,IP:127.0.0.1" \
+          2>/dev/null
+
+        echo -e "  ${GREEN}✓${NC} Self-signed certificates generated"
+    fi
 
     # Fix permissions
     chmod 600 "$CERT_DIR/server.key"
     chown -R "$USER:$USER" "$CERT_DIR"
-    echo -e "  ${GREEN}✓${NC} SSL certificates generated"
 fi
 
 # Setup port 443 redirect if requested
@@ -613,15 +766,19 @@ echo -e "${BLUE}-------------------------------------------------------${NC}"
 echo ""
 
 PI_IP=$(hostname -I | awk '{print $1}')
+PI_HOST=$(hostname)
 
 echo -e "${GREEN}Create your admin account:${NC}"
 if [ "$ENABLE_HTTPS" = "true" ]; then
     if [ "$USE_PORT_443" = "true" ]; then
+        echo -e "  ${YELLOW}https://$PI_HOST.local/setup${NC}"
         echo -e "  ${YELLOW}https://$PI_IP/setup${NC}"
     else
+        echo -e "  ${YELLOW}https://$PI_HOST.local:5000/setup${NC}"
         echo -e "  ${YELLOW}https://$PI_IP:5000/setup${NC}"
     fi
 else
+    echo -e "  ${YELLOW}http://$PI_HOST.local:5000/setup${NC}"
     echo -e "  ${YELLOW}http://$PI_IP:5000/setup${NC}"
 fi
 
@@ -637,6 +794,14 @@ echo "  Start:   sudo systemctl start stegasoo"
 echo "  Stop:    sudo systemctl stop stegasoo"
 echo "  Status:  sudo systemctl status stegasoo"
 echo "  Logs:    journalctl -u stegasoo -f"
+if [ "$STEGASOO_API_ENABLED" = "true" ]; then
+    echo ""
+    echo -e "${GREEN}REST API Commands:${NC}"
+    echo "  Start:   sudo systemctl start stegasoo-api"
+    echo "  Stop:    sudo systemctl stop stegasoo-api"
+    echo "  Status:  sudo systemctl status stegasoo-api"
+    echo "  Logs:    journalctl -u stegasoo-api -f"
+fi
 echo ""
 
 # Offer to start now
@@ -644,17 +809,27 @@ read -p "Start Stegasoo now? [Y/n] " -n 1 -r
 echo
 if [[ ! $REPLY =~ ^[Nn]$ ]]; then
     sudo systemctl start stegasoo
+    if [ "$STEGASOO_API_ENABLED" = "true" ]; then
+        sudo systemctl start stegasoo-api
+    fi
     sleep 2
     if systemctl is-active --quiet stegasoo; then
-        echo -e "${GREEN}✓ Stegasoo is running!${NC}"
+        echo -e "${GREEN}✓ Stegasoo Web UI is running!${NC}"
         if [ "$ENABLE_HTTPS" = "true" ]; then
             if [ "$USE_PORT_443" = "true" ]; then
-                echo -e "  Create admin: ${YELLOW}https://$PI_IP/setup${NC}"
+                echo -e "  Create admin: ${YELLOW}https://$PI_HOST.local/setup${NC} or ${YELLOW}https://$PI_IP/setup${NC}"
             else
-                echo -e "  Create admin: ${YELLOW}https://$PI_IP:5000/setup${NC}"
+                echo -e "  Create admin: ${YELLOW}https://$PI_HOST.local:5000/setup${NC} or ${YELLOW}https://$PI_IP:5000/setup${NC}"
             fi
         else
-            echo -e "  Create admin: ${YELLOW}http://$PI_IP:5000/setup${NC}"
+            echo -e "  Create admin: ${YELLOW}http://$PI_HOST.local:5000/setup${NC} or ${YELLOW}http://$PI_IP:5000/setup${NC}"
+        fi
+        if [ "$STEGASOO_API_ENABLED" = "true" ]; then
+            if systemctl is-active --quiet stegasoo-api; then
+                echo -e "${GREEN}✓ Stegasoo REST API is running on port 8000${NC}"
+            else
+                echo -e "${YELLOW}⚠ REST API failed to start. Check logs:${NC} journalctl -u stegasoo-api -f"
+            fi
         fi
     else
         echo -e "${RED}✗ Failed to start. Check logs:${NC} journalctl -u stegasoo -f"

scripts/build.sh

@@ -0,0 +1,98 @@
+#!/bin/bash
+# Stegasoo Build Script
+# Usage: ./build.sh [base|fast|full|clean]
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
+DOCKER_DIR="$PROJECT_DIR/docker"
+cd "$PROJECT_DIR"
+
+# Colors
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+CYAN='\033[0;36m'
+NC='\033[0m'
+
+# Detect docker compose command
+if docker compose version &>/dev/null; then
+    COMPOSE_CMD="docker compose"
+elif command -v docker-compose &>/dev/null; then
+    COMPOSE_CMD="docker-compose"
+else
+    echo -e "${RED}Error: docker compose not found${NC}"
+    exit 1
+fi
+
+# Check if we need sudo
+SUDO=""
+if ! docker ps &>/dev/null; then
+    SUDO="sudo"
+fi
+
+COMPOSE_FILE="$DOCKER_DIR/docker-compose.yml"
+
+case "${1:-fast}" in
+    base)
+        echo -e "${YELLOW}Building base image (this takes 5-10 minutes)...${NC}"
+        $SUDO docker build -f "$DOCKER_DIR/Dockerfile.base" -t stegasoo-base:latest .
+        echo -e "${GREEN}Base image built! Future builds will be fast.${NC}"
+        echo ""
+        echo "Optional: Push to registry for team use:"
+        echo "  docker tag stegasoo-base:latest yourregistry/stegasoo-base:latest"
+        echo "  docker push yourregistry/stegasoo-base:latest"
+        ;;
+
+    fast)
+        if ! $SUDO docker image inspect stegasoo-base:latest >/dev/null 2>&1; then
+            echo -e "${YELLOW}Base image not found. Building it first (one-time)...${NC}"
+            $0 base
+        fi
+        echo -e "${CYAN}Fast build using base image...${NC}"
+        $SUDO $COMPOSE_CMD -f "$COMPOSE_FILE" build
+        echo -e "${GREEN}Done! Start with: $COMPOSE_CMD -f docker/docker-compose.yml up -d${NC}"
+        ;;
+
+    full)
+        echo -e "${YELLOW}Full build from scratch (slow)...${NC}"
+        $SUDO $COMPOSE_CMD -f "$COMPOSE_FILE" build --no-cache
+        echo -e "${GREEN}Done! Start with: $COMPOSE_CMD -f docker/docker-compose.yml up -d${NC}"
+        ;;
+
+    clean)
+        echo -e "${YELLOW}Cleaning up...${NC}"
+        $SUDO $COMPOSE_CMD -f "$COMPOSE_FILE" down --rmi local -v 2>/dev/null || true
+        $SUDO docker rmi stegasoo-base:latest 2>/dev/null || true
+        echo -e "${GREEN}Cleaned!${NC}"
+        ;;
+
+    rebuild)
+        echo -e "${YELLOW}Full rebuild from scratch (no cache)...${NC}"
+        $SUDO $COMPOSE_CMD -f "$COMPOSE_FILE" down --rmi local -v 2>/dev/null || true
+        $SUDO docker rmi stegasoo-base:latest 2>/dev/null || true
+        $SUDO docker build --no-cache -f "$DOCKER_DIR/Dockerfile.base" -t stegasoo-base:latest .
+        $SUDO $COMPOSE_CMD -f "$COMPOSE_FILE" build --no-cache
+        echo -e "${GREEN}Done! Start with: $COMPOSE_CMD -f docker/docker-compose.yml up -d${NC}"
+        ;;
+
+    *)
+        echo -e "${CYAN}Stegasoo Build Script${NC}"
+        echo ""
+        echo "Usage: $0 [command]"
+        echo ""
+        echo "Commands:"
+        echo "  base    Build the base image (one-time, 5-10 min)"
+        echo "  fast    Fast build using base image (default, ~10 sec)"
+        echo "  full    Rebuild services without cache (uses existing base)"
+        echo "  rebuild Complete rebuild with no cache (base + services)"
+        echo "  clean   Remove all images and volumes"
+        echo ""
+        echo "Typical workflow:"
+        echo "  1. First time:   $0 base"
+        echo "  2. Daily dev:    $0 fast"
+        echo "  3. Deps change:  $0 base"
+        echo "  4. Nuclear:      $0 rebuild"
+        ;;
+esac

scripts/screenshots.sh

@@ -0,0 +1,93 @@
+#!/bin/bash
+# Capture Web UI screenshots for documentation
+# Requires: chromium, imagemagick
+# Usage: ./scripts/screenshots.sh [base_url]
+#
+# Modes:
+#   Default (auth disabled): Captures main UI pages
+#   With auth: Also captures login/setup/account pages
+#
+# Start server with: STEGASOO_AUTH_ENABLED=false python frontends/web/app.py
+
+set -e
+
+BASE_URL="${1:-http://localhost:5000}"
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
+OUTPUT_DIR="$PROJECT_DIR/data"
+WINDOW_SIZE="1280,900"
+
+echo "╔══════════════════════════════════════════╗"
+echo "║     Stegasoo Screenshot Capture          ║"
+echo "╚══════════════════════════════════════════╝"
+echo ""
+echo "Base URL: $BASE_URL"
+echo "Output:   $OUTPUT_DIR"
+echo ""
+
+# Check dependencies
+for cmd in chromium magick curl; do
+    if ! command -v "$cmd" &> /dev/null; then
+        echo "Error: $cmd not found"
+        exit 1
+    fi
+done
+
+# Check if server is running (-k for self-signed certs)
+if ! curl -sk "$BASE_URL" > /dev/null 2>&1; then
+    echo "Error: Server not responding at $BASE_URL"
+    echo "Start with: STEGASOO_AUTH_ENABLED=false python frontends/web/app.py"
+    exit 1
+fi
+
+# Capture a single screenshot
+capture() {
+    local name="$1"
+    local route="$2"
+    local url="$BASE_URL$route"
+
+    printf "  %-20s <- %s\n" "$name" "$route"
+    chromium --headless --screenshot="$OUTPUT_DIR/$name.png" \
+        --window-size="$WINDOW_SIZE" --hide-scrollbars \
+        --disable-gpu --no-sandbox --ignore-certificate-errors \
+        "$url" 2>/dev/null
+}
+
+echo "Capturing main pages..."
+echo ""
+
+# Core pages (always capture)
+capture "WebUI"          "/"
+capture "WebUI_Encode"   "/encode"
+capture "WebUI_Decode"   "/decode"
+capture "WebUI_Generate" "/generate"
+capture "WebUI_Tools"    "/tools"
+capture "WebUI_About"    "/about"
+
+echo ""
+echo "Capturing auth pages..."
+echo ""
+
+# Auth pages (may redirect if auth disabled, that's OK)
+capture "WebUI_Login"    "/login"
+capture "WebUI_Setup"    "/setup"
+capture "WebUI_Account"  "/account"
+capture "WebUI_Recover"  "/recover"
+
+echo ""
+echo "Converting to webp..."
+echo ""
+
+for png in "$OUTPUT_DIR"/WebUI*.png; do
+    [ -f "$png" ] || continue
+    name=$(basename "$png" .png)
+    printf "  %-20s -> %s.webp\n" "$name.png" "$name"
+    magick "$png" -quality 85 "$OUTPUT_DIR/$name.webp"
+    rm -f "$png"
+done
+
+echo ""
+echo "Done! Screenshots:"
+echo ""
+ls -lh "$OUTPUT_DIR"/WebUI*.webp 2>/dev/null | awk '{print "  " $NF " (" $5 ")"}'
+echo ""

scripts/setup-trusted-certs.sh

@@ -0,0 +1,149 @@
+#!/bin/bash
+#
+# Setup trusted HTTPS certificates for Stegasoo
+# Uses mkcert to create browser-trusted certs (no warning screens!)
+#
+# Usage: ./setup-trusted-certs.sh [hostname]
+#
+# This script:
+#   1. Installs mkcert if needed
+#   2. Creates a local CA (one-time)
+#   3. Generates certs for your hostname
+#   4. Shows how to trust the CA on other devices
+#
+
+set -e
+
+HOSTNAME="${1:-stegasoo.local}"
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$SCRIPT_DIR/.."
+CERT_DIR="$PROJECT_ROOT/frontends/web/certs"
+
+# Colors
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+CYAN='\033[0;36m'
+NC='\033[0m'
+
+echo ""
+echo -e "${CYAN}╔═══════════════════════════════════════════════════════════════╗${NC}"
+echo -e "${CYAN}║         Stegasoo Trusted Certificate Setup                    ║${NC}"
+echo -e "${CYAN}╚═══════════════════════════════════════════════════════════════╝${NC}"
+echo ""
+
+# Check/install mkcert
+install_mkcert() {
+    if command -v mkcert &> /dev/null; then
+        echo -e "${GREEN}✓${NC} mkcert already installed"
+        return
+    fi
+
+    echo -e "${YELLOW}Installing mkcert...${NC}"
+
+    # Detect OS and install
+    if [[ "$OSTYPE" == "darwin"* ]]; then
+        # macOS
+        if command -v brew &> /dev/null; then
+            brew install mkcert
+        else
+            echo -e "${RED}Please install Homebrew first: https://brew.sh${NC}"
+            exit 1
+        fi
+    elif [[ -f /etc/debian_version ]]; then
+        # Debian/Ubuntu/Raspberry Pi OS
+        sudo apt-get update
+        sudo apt-get install -y libnss3-tools
+
+        # Download mkcert binary
+        ARCH=$(dpkg --print-architecture)
+        if [[ "$ARCH" == "arm64" ]] || [[ "$ARCH" == "aarch64" ]]; then
+            MKCERT_URL="https://github.com/FiloSottile/mkcert/releases/latest/download/mkcert-linux-arm64"
+        else
+            MKCERT_URL="https://github.com/FiloSottile/mkcert/releases/latest/download/mkcert-linux-amd64"
+        fi
+
+        sudo curl -L "$MKCERT_URL" -o /usr/local/bin/mkcert
+        sudo chmod +x /usr/local/bin/mkcert
+    elif [[ -f /etc/arch-release ]]; then
+        # Arch Linux
+        sudo pacman -S mkcert
+    else
+        echo -e "${RED}Unsupported OS. Please install mkcert manually:${NC}"
+        echo "  https://github.com/FiloSottile/mkcert#installation"
+        exit 1
+    fi
+
+    echo -e "${GREEN}✓${NC} mkcert installed"
+}
+
+# Install local CA
+setup_ca() {
+    echo ""
+    echo -e "${CYAN}Setting up local Certificate Authority...${NC}"
+
+    if mkcert -install 2>/dev/null; then
+        echo -e "${GREEN}✓${NC} Local CA installed in system trust store"
+    else
+        echo -e "${YELLOW}!${NC} Could not auto-install CA (may need manual browser import)"
+    fi
+}
+
+# Generate certificates
+generate_certs() {
+    echo ""
+    echo -e "${CYAN}Generating trusted certificate for: ${YELLOW}$HOSTNAME${NC}"
+
+    mkdir -p "$CERT_DIR"
+    cd "$CERT_DIR"
+
+    # Generate cert for hostname + common local names
+    mkcert -key-file key.pem -cert-file cert.pem \
+        "$HOSTNAME" \
+        localhost \
+        127.0.0.1 \
+        ::1
+
+    echo -e "${GREEN}✓${NC} Certificates generated in: $CERT_DIR"
+}
+
+# Show CA location for other devices
+show_ca_info() {
+    CA_ROOT=$(mkcert -CAROOT)
+    CA_FILE="$CA_ROOT/rootCA.pem"
+
+    echo ""
+    echo -e "${CYAN}════════════════════════════════════════════════════════════════${NC}"
+    echo -e "${GREEN}  Setup Complete!${NC}"
+    echo -e "${CYAN}════════════════════════════════════════════════════════════════${NC}"
+    echo ""
+    echo "Your certificates are ready. Browsers on THIS machine will trust them."
+    echo ""
+    echo -e "${YELLOW}To trust on OTHER devices (phones, tablets, other computers):${NC}"
+    echo ""
+    echo "  1. Copy the CA certificate to that device:"
+    echo -e "     ${CYAN}$CA_FILE${NC}"
+    echo ""
+    echo "  2. Import it as a trusted CA:"
+    echo "     - iOS: AirDrop/email the file, Settings > Profile Downloaded > Install"
+    echo "     - Android: Settings > Security > Install from storage"
+    echo "     - Windows: Double-click > Install > Trusted Root CAs"
+    echo "     - macOS: Double-click > Keychain Access > Trust Always"
+    echo "     - Linux: Copy to /usr/local/share/ca-certificates/ && update-ca-certificates"
+    echo ""
+    echo -e "${YELLOW}Quick copy command:${NC}"
+    echo "  scp $CA_FILE user@device:/path/"
+    echo ""
+
+    # Offer to serve CA file via HTTP for easy phone download
+    echo -e "${YELLOW}Or serve the CA for easy phone download:${NC}"
+    echo "  python3 -m http.server 8080 -d $CA_ROOT"
+    echo "  Then visit: http://$(hostname -I | awk '{print $1}'):8080/rootCA.pem"
+    echo ""
+}
+
+# Main
+install_mkcert
+setup_ca
+generate_certs
+show_ca_info

scripts/smoke-test.sh

@@ -0,0 +1,333 @@
+#!/bin/bash
+#
+# Stegasoo Smoke Test
+# Tests all core functionality against a running instance (Pi, Docker, or dev)
+#
+# Usage: ./smoke-test.sh [host] [port] [user] [pass]
+#
+# Examples:
+#   ./smoke-test.sh                          # Pi default (stegasoo.local:443)
+#   ./smoke-test.sh localhost 5000           # Docker default
+#   ./smoke-test.sh 192.168.1.100 5000       # Custom host
+#
+
+set -e
+
+# Configuration
+HOST="${1:-stegasoo.local}"
+PORT="${2:-443}"
+USER="${3:-admin}"
+PASS="${4:-stegasoo}"
+
+# Build URL (don't include :443 since it's default for https)
+if [ "$PORT" = "443" ]; then
+    BASE_URL="https://$HOST"
+else
+    BASE_URL="https://$HOST:$PORT"
+fi
+COOKIE_JAR="/tmp/stegasoo_smoke_cookies.txt"
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+TEST_DATA="$SCRIPT_DIR/../test_data"
+
+# Colors
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+CYAN='\033[0;36m'
+NC='\033[0m'
+
+PASSED=0
+FAILED=0
+
+# -----------------------------------------------------------------------------
+# Helper functions
+# -----------------------------------------------------------------------------
+
+log_test() {
+    echo -e "${CYAN}[TEST]${NC} $1"
+}
+
+log_pass() {
+    echo -e "${GREEN}[PASS]${NC} $1"
+    PASSED=$((PASSED + 1))
+}
+
+log_fail() {
+    echo -e "${RED}[FAIL]${NC} $1"
+    FAILED=$((FAILED + 1))
+}
+
+curl_get() {
+    curl -sk "$BASE_URL$1" -b "$COOKIE_JAR" -c "$COOKIE_JAR" "${@:2}"
+}
+
+curl_post() {
+    curl -sk -X POST "$BASE_URL$1" -b "$COOKIE_JAR" -c "$COOKIE_JAR" "${@:2}"
+}
+
+wait_for_job() {
+    local endpoint="$1"
+    local job_id="$2"
+    local max_polls="${3:-30}"
+
+    for i in $(seq 1 $max_polls); do
+        sleep 1
+        result=$(curl_get "$endpoint/$job_id")
+        if echo "$result" | grep -q '"status":\s*"complete"'; then
+            echo "$result"
+            return 0
+        fi
+        if echo "$result" | grep -q '"status":\s*"error"'; then
+            echo "$result"
+            return 1
+        fi
+    done
+    echo '{"status":"timeout"}'
+    return 1
+}
+
+# -----------------------------------------------------------------------------
+# Tests
+# -----------------------------------------------------------------------------
+
+test_connectivity() {
+    log_test "Connectivity to $BASE_URL"
+    if curl -sk --connect-timeout 5 "$BASE_URL" -o /dev/null; then
+        log_pass "Server reachable"
+    else
+        log_fail "Cannot reach server"
+        exit 1
+    fi
+}
+
+test_setup_or_login() {
+    log_test "Setup/Login"
+
+    # Check if setup needed
+    response=$(curl_get "/" -L -o /dev/null -w "%{url_effective}")
+
+    if echo "$response" | grep -q "/setup"; then
+        log_test "Completing first-time setup..."
+        curl_post "/setup" \
+            -d "username=$USER" \
+            -d "password=$PASS" \
+            -d "password_confirm=$PASS" \
+            -L -o /dev/null
+    fi
+
+    # Login
+    curl_get "/login" -o /dev/null  # Get session
+    curl_post "/login" \
+        -d "username=$USER" \
+        -d "password=$PASS" \
+        -L -o /dev/null
+
+    # Verify logged in
+    code=$(curl_get "/encode" -o /dev/null -w "%{http_code}")
+    if [ "$code" = "200" ]; then
+        log_pass "Authenticated successfully"
+    else
+        log_fail "Authentication failed (got $code)"
+    fi
+}
+
+test_pages() {
+    log_test "Page accessibility"
+
+    local pages="encode decode generate tools about"
+    local all_pass=true
+
+    for page in $pages; do
+        code=$(curl_get "/$page" -o /dev/null -w "%{http_code}")
+        if [ "$code" = "200" ]; then
+            echo -e "  ${GREEN}✓${NC} /$page"
+        else
+            echo -e "  ${RED}✗${NC} /$page ($code)"
+            all_pass=false
+        fi
+    done
+
+    if $all_pass; then
+        log_pass "All pages accessible"
+    else
+        log_fail "Some pages inaccessible"
+    fi
+}
+
+test_encode_decode_dct() {
+    log_test "DCT Encode/Decode round trip"
+
+    local message="DCT smoke test $(date +%s)"
+
+    # Encode
+    response=$(curl_post "/encode" \
+        -F "reference_photo=@$TEST_DATA/ref.jpg" \
+        -F "carrier=@$TEST_DATA/carrier.jpg" \
+        -F "message=$message" \
+        -F "passphrase=tower booty sunny windy" \
+        -F "pin=727643678" \
+        -F "embed_mode=dct" \
+        -F "channel_key=auto" \
+        -F "async=true")
+
+    job_id=$(echo "$response" | grep -oP '"job_id":\s*"[^"]+"' | cut -d'"' -f4)
+
+    if [ -z "$job_id" ]; then
+        log_fail "DCT encode - no job ID returned"
+        return
+    fi
+
+    # Wait for encode
+    result=$(wait_for_job "/encode/status" "$job_id" 15)
+    if ! echo "$result" | grep -q '"status":\s*"complete"'; then
+        log_fail "DCT encode timeout or error"
+        return
+    fi
+
+    file_id=$(echo "$result" | grep -oP '"file_id":\s*"[^"]+"' | cut -d'"' -f4)
+    curl_get "/encode/download/$file_id" -o /tmp/stego_dct_test.jpg
+
+    echo -e "  ${GREEN}✓${NC} Encoded $(ls -lh /tmp/stego_dct_test.jpg | awk '{print $5}')"
+
+    # Decode
+    response=$(curl_post "/decode" \
+        -F "reference_photo=@$TEST_DATA/ref.jpg" \
+        -F "stego_image=@/tmp/stego_dct_test.jpg" \
+        -F "passphrase=tower booty sunny windy" \
+        -F "pin=727643678" \
+        -F "embed_mode=auto" \
+        -F "channel_key=auto" \
+        -F "async=true")
+
+    job_id=$(echo "$response" | grep -oP '"job_id":\s*"[^"]+"' | cut -d'"' -f4)
+
+    # Wait for decode (DCT is slower on Pi)
+    result=$(wait_for_job "/decode/status" "$job_id" 60)
+
+    if echo "$result" | grep -q "$message"; then
+        log_pass "DCT round trip - message verified"
+    else
+        log_fail "DCT decode - message mismatch"
+        echo "  Expected: $message"
+        echo "  Got: $result"
+    fi
+}
+
+test_encode_decode_lsb() {
+    log_test "LSB Encode/Decode round trip"
+
+    local message="LSB smoke test $(date +%s)"
+
+    # Encode
+    response=$(curl_post "/encode" \
+        -F "reference_photo=@$TEST_DATA/ref.jpg" \
+        -F "carrier=@$TEST_DATA/carrier.jpg" \
+        -F "message=$message" \
+        -F "passphrase=tower booty sunny windy" \
+        -F "pin=727643678" \
+        -F "embed_mode=lsb" \
+        -F "channel_key=auto" \
+        -F "async=true")
+
+    job_id=$(echo "$response" | grep -oP '"job_id":\s*"[^"]+"' | cut -d'"' -f4)
+
+    if [ -z "$job_id" ]; then
+        log_fail "LSB encode - no job ID returned"
+        return
+    fi
+
+    result=$(wait_for_job "/encode/status" "$job_id" 10)
+    if ! echo "$result" | grep -q '"status":\s*"complete"'; then
+        log_fail "LSB encode timeout or error"
+        return
+    fi
+
+    file_id=$(echo "$result" | grep -oP '"file_id":\s*"[^"]+"' | cut -d'"' -f4)
+    curl_get "/encode/download/$file_id" -o /tmp/stego_lsb_test.png
+
+    echo -e "  ${GREEN}✓${NC} Encoded $(ls -lh /tmp/stego_lsb_test.png | awk '{print $5}')"
+
+    # Decode
+    response=$(curl_post "/decode" \
+        -F "reference_photo=@$TEST_DATA/ref.jpg" \
+        -F "stego_image=@/tmp/stego_lsb_test.png" \
+        -F "passphrase=tower booty sunny windy" \
+        -F "pin=727643678" \
+        -F "embed_mode=lsb" \
+        -F "channel_key=auto" \
+        -F "async=true")
+
+    job_id=$(echo "$response" | grep -oP '"job_id":\s*"[^"]+"' | cut -d'"' -f4)
+    result=$(wait_for_job "/decode/status" "$job_id" 15)
+
+    if echo "$result" | grep -q "$message"; then
+        log_pass "LSB round trip - message verified"
+    else
+        log_fail "LSB decode - message mismatch"
+    fi
+}
+
+test_tools() {
+    log_test "Tools endpoints"
+
+    # Capacity check
+    response=$(curl_post "/api/tools/capacity" \
+        -F "image=@$TEST_DATA/carrier.jpg" \
+        -w "%{http_code}" -o /tmp/capacity_result.json)
+
+    if [ "$response" = "200" ]; then
+        echo -e "  ${GREEN}✓${NC} Capacity check"
+    else
+        echo -e "  ${RED}✗${NC} Capacity check ($response)"
+    fi
+
+    # EXIF read
+    response=$(curl_post "/api/tools/exif" \
+        -F "image=@$TEST_DATA/carrier.jpg" \
+        -w "%{http_code}" -o /tmp/exif_result.json)
+
+    if [ "$response" = "200" ]; then
+        echo -e "  ${GREEN}✓${NC} EXIF read"
+        log_pass "Tools API works"
+    else
+        echo -e "  ${RED}✗${NC} EXIF read ($response)"
+        log_fail "Tools API failed"
+    fi
+}
+
+# -----------------------------------------------------------------------------
+# Main
+# -----------------------------------------------------------------------------
+
+echo ""
+echo -e "${CYAN}╔═══════════════════════════════════════════════════════════════╗${NC}"
+echo -e "${CYAN}║              Stegasoo Smoke Test                              ║${NC}"
+echo -e "${CYAN}╚═══════════════════════════════════════════════════════════════╝${NC}"
+echo ""
+echo -e "Target: ${YELLOW}$BASE_URL${NC}"
+echo -e "User:   ${YELLOW}$USER${NC}"
+echo ""
+
+# Clean up
+rm -f "$COOKIE_JAR" /tmp/stego_*_test.* /tmp/exif_stripped.jpg
+
+# Run tests
+test_connectivity
+test_setup_or_login
+test_pages
+test_encode_decode_lsb
+test_encode_decode_dct
+test_tools
+
+# Summary
+echo ""
+echo -e "${CYAN}════════════════════════════════════════════════════════════════${NC}"
+echo -e "Results: ${GREEN}$PASSED passed${NC}, ${RED}$FAILED failed${NC}"
+echo -e "${CYAN}════════════════════════════════════════════════════════════════${NC}"
+
+# Clean up
+rm -f "$COOKIE_JAR"
+
+if [ $FAILED -gt 0 ]; then
+    exit 1
+fi

src/stegasoo/__init__.py

@@ -7,7 +7,7 @@ Changes in v4.0.0:
 - encode() and decode() now accept channel_key parameter
 """
 
-__version__ = "4.1.3"
+__version__ = "4.2.0"
 
 # Core functionality
 # Channel key management (v4.0.0)

src/stegasoo/channel.py

@@ -47,6 +47,80 @@ CONFIG_LOCATIONS = [
     Path.home() / ".stegasoo" / "channel.key",  # User config
 ]
 
+# Encrypted config marker
+ENCRYPTED_PREFIX = "ENC:"
+
+
+def _get_machine_key() -> bytes:
+    """
+    Get a machine-specific key for encrypting stored channel keys.
+
+    Uses /etc/machine-id on Linux, falls back to hostname hash.
+    This ties the encrypted key to this specific machine.
+    """
+    machine_id = None
+
+    # Try Linux machine-id
+    try:
+        machine_id = Path("/etc/machine-id").read_text().strip()
+    except (OSError, FileNotFoundError):
+        pass
+
+    # Fallback to hostname
+    if not machine_id:
+        import socket
+        machine_id = socket.gethostname()
+
+    # Hash to get consistent 32 bytes
+    return hashlib.sha256(machine_id.encode()).digest()
+
+
+def _encrypt_for_storage(plaintext: str) -> str:
+    """
+    Encrypt a channel key for storage using machine-specific key.
+
+    Returns ENC: prefixed base64 string.
+    """
+    import base64
+
+    key = _get_machine_key()
+    plaintext_bytes = plaintext.encode()
+
+    # XOR with key (cycling if needed)
+    encrypted = bytes(
+        pb ^ key[i % len(key)]
+        for i, pb in enumerate(plaintext_bytes)
+    )
+
+    return ENCRYPTED_PREFIX + base64.b64encode(encrypted).decode()
+
+
+def _decrypt_from_storage(stored: str) -> str | None:
+    """
+    Decrypt a stored channel key.
+
+    Returns None if decryption fails or format is invalid.
+    """
+    import base64
+
+    if not stored.startswith(ENCRYPTED_PREFIX):
+        # Not encrypted, return as-is (legacy plaintext)
+        return stored
+
+    try:
+        encrypted = base64.b64decode(stored[len(ENCRYPTED_PREFIX):])
+        key = _get_machine_key()
+
+        # XOR to decrypt
+        decrypted = bytes(
+            eb ^ key[i % len(key)]
+            for i, eb in enumerate(encrypted)
+        )
+
+        return decrypted.decode()
+    except Exception:
+        return None
+
 
 def generate_channel_key() -> str:
     """
@@ -154,11 +228,13 @@ def get_channel_key() -> str | None:
         else:
             debug.print(f"Warning: Invalid {CHANNEL_KEY_ENV_VAR} format, ignoring")
 
-    # 2. Check config files
+    # 2. Check config files (may be encrypted)
     for config_path in CONFIG_LOCATIONS:
         if config_path.exists():
             try:
-                key = config_path.read_text().strip()
+                stored = config_path.read_text().strip()
+                # Decrypt if encrypted, otherwise use as-is (legacy)
+                key = _decrypt_from_storage(stored)
                 if key and validate_channel_key(key):
                     debug.print(f"Channel key from {config_path}: {get_channel_fingerprint(key)}")
                     return format_channel_key(key)
@@ -200,8 +276,9 @@ def set_channel_key(key: str, location: str = "project") -> Path:
     # Create directory if needed
     config_path.parent.mkdir(parents=True, exist_ok=True)
 
-    # Write key with newline
-    config_path.write_text(formatted + "\n")
+    # Encrypt and write (tied to this machine's identity)
+    encrypted = _encrypt_for_storage(formatted)
+    config_path.write_text(encrypted + "\n")
 
     # Set restrictive permissions (owner read/write only)
     try:
@@ -334,11 +411,12 @@ def get_channel_status() -> dict:
             for config_path in CONFIG_LOCATIONS:
                 if config_path.exists():
                     try:
-                        file_key = config_path.read_text().strip()
-                        if file_key and format_channel_key(file_key) == key:
+                        stored = config_path.read_text().strip()
+                        file_key = _decrypt_from_storage(stored)
+                        if file_key and validate_channel_key(file_key) and format_channel_key(file_key) == key:
                             source = str(config_path)
                             break
-                    except (OSError, PermissionError):
+                    except (OSError, PermissionError, ValueError):
                         continue
 
         return {

src/stegasoo/cli.py

@@ -1,7 +1,69 @@
 """
 Stegasoo CLI Module (v3.2.0)
 
-Command-line interface with batch processing and compression support.
+A proper CLI architecture using Click. This module demonstrates several
+important patterns for building production-quality command-line tools:
+
+PATTERN: COMMAND GROUPS
+=======================
+Click's @group decorator creates a hierarchy of commands:
+
+    stegasoo                     <- Main entry point
+    ├── encode                   <- Simple commands at root level
+    ├── decode
+    ├── generate
+    ├── info
+    ├── batch/                   <- Group for related commands
+    │   ├── encode
+    │   ├── decode
+    │   └── check
+    ├── channel/                 <- Another group
+    │   ├── generate
+    │   ├── show
+    │   ├── status
+    │   ├── qr
+    │   └── clear
+    ├── tools/                   <- Utility group
+    │   ├── capacity
+    │   ├── strip
+    │   ├── peek
+    │   └── exif
+    └── admin/                   <- Administration group
+        ├── recover
+        └── generate-key
+
+PATTERN: JSON OUTPUT MODE
+=========================
+Every command supports --json for machine-readable output. The pattern:
+
+    @click.pass_context
+    def my_command(ctx, ...):
+        if ctx.obj.get("json"):
+            click.echo(json.dumps(result, indent=2))
+        else:
+            # Human-readable output with colors/formatting
+            click.echo(f"✓ Success: {result}")
+
+This makes the CLI scriptable - you can pipe to jq, use in shell scripts, etc.
+
+PATTERN: SENSITIVE INPUT
+========================
+Passwords/secrets use Click's secure prompts:
+
+    @click.option("--passphrase", prompt=True, hide_input=True,
+                  confirmation_prompt=True, help="Passphrase")
+
+- prompt=True: Asks if not provided
+- hide_input=True: No echo (like sudo)
+- confirmation_prompt=True: "Repeat for confirmation"
+
+PATTERN: DRY-RUN MODE
+=====================
+For destructive or slow operations, --dry-run shows what WOULD happen:
+
+    if dry_run:
+        click.echo(f"Would encode to {output}")
+        return
 
 Changes in v3.2.0:
 - Updated to use DEFAULT_PASSPHRASE_WORDS (consistency with v3.2.0 naming)
@@ -18,12 +80,6 @@ from .batch import (
     batch_capacity_check,
     print_batch_result,
 )
-from .compression import (
-    HAS_LZ4,
-    CompressionAlgorithm,
-    algorithm_name,
-    get_available_algorithms,
-)
 from .constants import (
     DEFAULT_PASSPHRASE_WORDS,  # v3.2.0: renamed from DEFAULT_PHRASE_WORDS
     DEFAULT_PIN_LENGTH,
@@ -32,10 +88,23 @@ from .constants import (
     __version__,
 )
 
-# Click context settings
+# Click context settings - these apply to all commands
+# help_option_names lets users use either -h or --help
 CONTEXT_SETTINGS = dict(help_option_names=["-h", "--help"])
 
 
+# =============================================================================
+# ROOT GROUP - The main entry point
+# =============================================================================
+#
+# @click.group() creates a command group. The function becomes both:
+# 1. A callable that sets up shared state (ctx.obj)
+# 2. A container for subcommands via @cli.command() decorators
+#
+# The context object (ctx.obj) is passed down to all subcommands.
+# We use it to share the --json flag across the entire CLI.
+
+
 @click.group(context_settings=CONTEXT_SETTINGS)
 @click.version_option(__version__, "-v", "--version")
 @click.option("--json", "json_output", is_flag=True, help="Output results as JSON")
@@ -46,6 +115,8 @@ def cli(ctx, json_output):
 
     Hide messages in images using PIN + passphrase security.
     """
+    # ensure_object(dict) creates ctx.obj if it doesn't exist
+    # This prevents "NoneType has no attribute" errors
     ctx.ensure_object(dict)
     ctx.obj["json"] = json_output
 
@@ -53,6 +124,31 @@ def cli(ctx, json_output):
 # =============================================================================
 # ENCODE COMMANDS
 # =============================================================================
+#
+# The encode command demonstrates several Click patterns:
+#
+# 1. ARGUMENT vs OPTION
+#    - Arguments are positional: `stegasoo encode photo.png`
+#    - Options have flags: `stegasoo encode -m "message" --pin 1234`
+#    Rule of thumb: required inputs → arguments, optional/secret → options
+#
+# 2. MUTUAL EXCLUSIVITY
+#    We need either --message OR --file, not both. Click doesn't have built-in
+#    mutual exclusivity, so we check manually:
+#
+#        if not message and not file_payload:
+#            raise click.UsageError("Either --message or --file is required")
+#
+# 3. TYPE VALIDATION
+#    Click validates types automatically:
+#    - type=click.Path(exists=True) → file must exist
+#    - type=click.Choice(["a", "b"]) → must be one of these values
+#    - type=int → must be an integer
+#
+# 4. DEFAULT VALUES
+#    Options can have smart defaults:
+#    - default="zlib" → use this if not specified
+#    - default=True with is_flag=True → boolean flag defaults to on
 
 
 @cli.command()
@@ -81,19 +177,10 @@ def cli(ctx, json_output):
     help="Passphrase (recommend 4+ words)",
 )
 @click.option("--pin", prompt=True, hide_input=True, confirmation_prompt=True, help="PIN code")
-@click.option(
-    "--compress/--no-compress", default=True, help="Enable/disable compression (default: enabled)"
-)
-@click.option(
-    "--algorithm",
-    type=click.Choice(["zlib", "lz4", "none"]),
-    default="zlib",
-    help="Compression algorithm",
-)
 @click.option("--dry-run", is_flag=True, help="Show capacity usage without encoding")
 @click.pass_context
 def encode(
-    ctx, carrier, reference, message, file_payload, output, passphrase, pin, compress, algorithm, dry_run
+    ctx, carrier, reference, message, file_payload, output, passphrase, pin, dry_run
 ):
     """
     Encode a message or file into an image.
@@ -112,18 +199,6 @@ def encode(
     if not message and not file_payload:
         raise click.UsageError("Either --message or --file is required")
 
-    # Parse compression algorithm
-    algo_map = {
-        "zlib": CompressionAlgorithm.ZLIB,
-        "lz4": CompressionAlgorithm.LZ4,
-        "none": CompressionAlgorithm.NONE,
-    }
-    compression_algo = algo_map[algorithm] if compress else CompressionAlgorithm.NONE
-
-    if algorithm == "lz4" and not HAS_LZ4:
-        click.echo("Warning: LZ4 not available, falling back to zlib", err=True)
-        compression_algo = CompressionAlgorithm.ZLIB
-
     # Calculate payload size
     if file_payload:
         payload_size = Path(file_payload).stat().st_size
@@ -145,7 +220,6 @@ def encode(
             "capacity_bytes": capacity_bytes,
             "payload_type": payload_type,
             "payload_size": payload_size,
-            "compression": algorithm_name(compression_algo),
             "usage_percent": round(payload_size / capacity_bytes * 100, 1),
             "fits": payload_size < capacity_bytes,
         }
@@ -157,7 +231,6 @@ def encode(
             click.echo(f"Reference: {reference}")
             click.echo(f"Capacity: {capacity_bytes:,} bytes ({capacity_bytes//1024} KB)")
             click.echo(f"Payload: {payload_size:,} bytes ({payload_type})")
-            click.echo(f"Compression: {algorithm_name(compression_algo)}")
             click.echo(f"Usage: {result['usage_percent']}%")
             click.echo(f"Status: {'✓ Fits' if result['fits'] else '✗ Too large'}")
         return
@@ -204,7 +277,6 @@ def encode(
                         "reference": reference,
                         "output": output,
                         "payload_type": payload_type,
-                        "compression": algorithm_name(compression_algo),
                     },
                     indent=2,
                 )
@@ -212,7 +284,6 @@ def encode(
         else:
             click.echo(f"✓ Encoded {payload_type} to {output}")
             click.echo(f"  Reference: {reference}")
-            click.echo(f"  Compression: {algorithm_name(compression_algo)}")
 
     except Exception as e:
         if ctx.obj.get("json"):
@@ -320,6 +391,32 @@ def decode(ctx, image, reference, passphrase, pin, output):
 # =============================================================================
 # BATCH COMMANDS
 # =============================================================================
+#
+# Batch processing demonstrates:
+#
+# 1. SUBGROUPS
+#    @cli.group() creates a nested command group:
+#        stegasoo batch encode *.png
+#        stegasoo batch decode *.png
+#        stegasoo batch check *.png
+#
+# 2. VARIADIC ARGUMENTS
+#    nargs=-1 accepts multiple arguments:
+#        @click.argument("images", nargs=-1, required=True)
+#    This lets users do: `stegasoo batch encode img1.png img2.png img3.png`
+#    Or with shell expansion: `stegasoo batch encode *.png`
+#
+# 3. PROGRESS CALLBACKS
+#    We pass a callback to the BatchProcessor for real-time updates:
+#
+#        def progress(current, total, item):
+#            click.echo(f"[{current}/{total}] {item.input_path.name}")
+#
+#        processor.batch_encode(..., progress_callback=progress)
+#
+# 4. PARALLEL PROCESSING
+#    --jobs/-j controls worker count. Default is 4 for good balance between
+#    speed and memory usage. Each worker loads images into memory.
 
 
 @cli.group()
@@ -346,13 +443,6 @@ def batch():
     help="Passphrase (recommend 4+ words)",
 )
 @click.option("--pin", prompt=True, hide_input=True, confirmation_prompt=True, help="PIN code")
-@click.option("--compress/--no-compress", default=True, help="Enable/disable compression")
-@click.option(
-    "--algorithm",
-    type=click.Choice(["zlib", "lz4", "none"]),
-    default="zlib",
-    help="Compression algorithm",
-)
 @click.option("-r", "--recursive", is_flag=True, help="Search directories recursively")
 @click.option("-j", "--jobs", default=4, help="Parallel workers (default: 4)")
 @click.option("-v", "--verbose", is_flag=True, help="Show detailed output")
@@ -366,8 +456,6 @@ def batch_encode(
     suffix,
     passphrase,
     pin,
-    compress,
-    algorithm,
     recursive,
     jobs,
     verbose,
@@ -402,7 +490,6 @@ def batch_encode(
         output_dir=Path(output_dir) if output_dir else None,
         output_suffix=suffix,
         credentials=credentials,
-        compress=compress,
         recursive=recursive,
         progress_callback=progress if not ctx.obj.get("json") else None,
     )
@@ -595,10 +682,10 @@ def info(ctx, full):
 
     # Check for DCT support
     try:
-        from .dct_steganography import HAS_SCIPY, HAS_JPEGIO
-        HAS_DCT = HAS_SCIPY and HAS_JPEGIO
+        from .dct_steganography import HAS_JPEGIO, HAS_SCIPY
+        has_dct = HAS_SCIPY and HAS_JPEGIO
     except ImportError:
-        HAS_DCT = False
+        has_dct = False
 
     # Check service status
     service_status = "unknown"
@@ -637,7 +724,7 @@ def info(ctx, full):
     channel_fingerprint = None
     channel_source = None
     try:
-        from .channel import get_channel_key, get_channel_fingerprint, get_channel_status
+        from .channel import get_channel_fingerprint, get_channel_key, get_channel_status
         key = get_channel_key()
         if key:
             channel_fingerprint = get_channel_fingerprint(key)
@@ -688,15 +775,11 @@ def info(ctx, full):
         "version": __version__,
         "service": service_status,
         "url": service_url,
-        "dct_support": HAS_DCT,
+        "dct_support": has_dct,
         "channel": {
             "fingerprint": channel_fingerprint,
             "source": channel_source,
         } if channel_fingerprint else None,
-        "compression": {
-            "available": [algorithm_name(a) for a in get_available_algorithms()],
-            "lz4_installed": HAS_LZ4,
-        },
         "limits": {
             "max_message_bytes": MAX_MESSAGE_SIZE,
             "max_file_payload_bytes": MAX_FILE_PAYLOAD_SIZE,
@@ -718,11 +801,11 @@ def info(ctx, full):
 
         # Service status
         if service_status == "active":
-            click.echo(f"  Service:     \033[32m● running\033[0m")
+            click.echo("  Service:     \033[32m● running\033[0m")
             if service_url:
                 click.echo(f"  URL:         {service_url}")
         elif service_status == "inactive":
-            click.echo(f"  Service:     \033[31m○ stopped\033[0m")
+            click.echo("  Service:     \033[31m○ stopped\033[0m")
         else:
             click.echo(f"  Service:     \033[33m? {service_status}\033[0m")
 
@@ -731,10 +814,10 @@ def info(ctx, full):
             masked = f"{channel_fingerprint[:4]}••••••••{channel_fingerprint[-4:]}"
             click.echo(f"  Channel:     {masked}")
         else:
-            click.echo(f"  Channel:     \033[33mpublic\033[0m")
+            click.echo("  Channel:     public")
 
         # DCT
-        dct_status = "\033[32m✓ enabled\033[0m" if HAS_DCT else "\033[31m✗ disabled\033[0m"
+        dct_status = "\033[32m✓ enabled\033[0m" if has_dct else "\033[31m✗ disabled\033[0m"
         click.echo(f"  DCT:         {dct_status}")
 
         # System info (if --full)

src/stegasoo/compression.py

@@ -17,6 +17,14 @@ try:
 except ImportError:
     HAS_LZ4 = False
 
+# Optional ZSTD support (best ratio, fast)
+try:
+    import zstandard as zstd
+
+    HAS_ZSTD = True
+except ImportError:
+    HAS_ZSTD = False
+
 
 class CompressionAlgorithm(IntEnum):
     """Supported compression algorithms."""
@@ -24,6 +32,7 @@ class CompressionAlgorithm(IntEnum):
     NONE = 0
     ZLIB = 1
     LZ4 = 2
+    ZSTD = 3  # v4.2.0: Best ratio, fast compression
 
 
 # Magic bytes for compressed payloads
@@ -72,6 +81,15 @@ def compress(data: bytes, algorithm: CompressionAlgorithm = CompressionAlgorithm
             algorithm = CompressionAlgorithm.ZLIB
         else:
             compressed = lz4.frame.compress(data)
+
+    elif algorithm == CompressionAlgorithm.ZSTD:
+        if not HAS_ZSTD:
+            # Fall back to zlib if ZSTD not available
+            compressed = zlib.compress(data, level=ZLIB_LEVEL)
+            algorithm = CompressionAlgorithm.ZLIB
+        else:
+            cctx = zstd.ZstdCompressor(level=19)  # High compression level
+            compressed = cctx.compress(data)
     else:
         raise CompressionError(f"Unknown compression algorithm: {algorithm}")
 
@@ -123,6 +141,15 @@ def decompress(data: bytes) -> bytes:
             result = lz4.frame.decompress(compressed_data)
         except Exception as e:
             raise CompressionError(f"LZ4 decompression failed: {e}")
+
+    elif algorithm == CompressionAlgorithm.ZSTD:
+        if not HAS_ZSTD:
+            raise CompressionError("ZSTD compression used but zstandard package not installed")
+        try:
+            dctx = zstd.ZstdDecompressor()
+            result = dctx.decompress(compressed_data)
+        except Exception as e:
+            raise CompressionError(f"ZSTD decompression failed: {e}")
     else:
         raise CompressionError(f"Unknown compression algorithm: {algorithm}")
 
@@ -181,6 +208,9 @@ def estimate_compressed_size(
         compressed_sample = zlib.compress(sample, level=ZLIB_LEVEL)
     elif algorithm == CompressionAlgorithm.LZ4 and HAS_LZ4:
         compressed_sample = lz4.frame.compress(sample)
+    elif algorithm == CompressionAlgorithm.ZSTD and HAS_ZSTD:
+        cctx = zstd.ZstdCompressor(level=19)
+        compressed_sample = cctx.compress(sample)
     else:
         compressed_sample = zlib.compress(sample, level=ZLIB_LEVEL)
 
@@ -195,14 +225,24 @@ def get_available_algorithms() -> list[CompressionAlgorithm]:
     algorithms = [CompressionAlgorithm.NONE, CompressionAlgorithm.ZLIB]
     if HAS_LZ4:
         algorithms.append(CompressionAlgorithm.LZ4)
+    if HAS_ZSTD:
+        algorithms.append(CompressionAlgorithm.ZSTD)
     return algorithms
 
 
+def get_best_algorithm() -> CompressionAlgorithm:
+    """Get the best available compression algorithm (prefer ZSTD > ZLIB > LZ4)."""
+    if HAS_ZSTD:
+        return CompressionAlgorithm.ZSTD
+    return CompressionAlgorithm.ZLIB
+
+
 def algorithm_name(algo: CompressionAlgorithm) -> str:
     """Get human-readable algorithm name."""
     names = {
         CompressionAlgorithm.NONE: "None",
         CompressionAlgorithm.ZLIB: "Zlib (deflate)",
         CompressionAlgorithm.LZ4: "LZ4 (fast)",
+        CompressionAlgorithm.ZSTD: "Zstd (best)",
     }
     return names.get(algo, "Unknown")

src/stegasoo/constants.py

@@ -1,9 +1,15 @@
 """
-Stegasoo Constants and Configuration (v4.0.2 - Web UI Authentication)
+Stegasoo Constants and Configuration (v4.2.0 - Performance & Compression)
 
 Central location for all magic numbers, limits, and crypto parameters.
 All version numbers, limits, and configuration values should be defined here.
 
+CHANGES in v4.2.0:
+- Added zstd compression for QR codes (better ratio than zlib)
+- RSA key size capped at 3072 bits (4096 too large for QR codes)
+- Progress bar improvements for encode/decode operations
+- File auto-expire increased to 10 minutes
+
 CHANGES in v4.0.2:
 - Added Web UI authentication with SQLite3 user storage
 - Added optional HTTPS with auto-generated self-signed certificates
@@ -25,7 +31,7 @@ from pathlib import Path
 # VERSION
 # ============================================================================
 
-__version__ = "4.1.3"
+__version__ = "4.2.0"
 
 # ============================================================================
 # FILE FORMAT
@@ -98,7 +104,7 @@ DEFAULT_PHRASE_WORDS = DEFAULT_PASSPHRASE_WORDS
 
 # RSA configuration
 MIN_RSA_BITS = 2048
-VALID_RSA_SIZES = (2048, 3072, 4096)
+VALID_RSA_SIZES = (2048, 3072)  # 4096 removed - too large for QR codes
 DEFAULT_RSA_BITS = 2048
 
 MIN_KEY_PASSWORD_LENGTH = 8
@@ -108,8 +114,8 @@ MIN_KEY_PASSWORD_LENGTH = 8
 # ============================================================================
 
 # Temporary file storage
-TEMP_FILE_EXPIRY = 300  # 5 minutes in seconds
-TEMP_FILE_EXPIRY_MINUTES = 5
+TEMP_FILE_EXPIRY = 600  # 10 minutes in seconds
+TEMP_FILE_EXPIRY_MINUTES = 10
 
 # Thumbnail settings
 THUMBNAIL_SIZE = (250, 250)  # Maximum dimensions for thumbnails

src/stegasoo/crypto.py

@@ -1,18 +1,26 @@
 """
 Stegasoo Cryptographic Functions (v4.0.0 - Channel Key Support)
 
-Key derivation, encryption, and decryption using AES-256-GCM.
-Supports both text messages and binary file payloads.
+This is the crypto layer - where we turn plaintext into indecipherable noise.
 
-BREAKING CHANGES in v4.0.0:
-- Added channel key support for deployment/group isolation
-- Messages encoded with a channel key require the same key to decode
-- Channel key can be configured via environment, config file, or explicit parameter
-- FORMAT_VERSION bumped to 5
+The security model is multi-factor:
+┌────────────────────────────────────────────────────────────────────┐
+│  SOMETHING YOU HAVE          SOMETHING YOU KNOW                    │
+│  ├─ Reference photo          ├─ Passphrase (4+ BIP-39 words)      │
+│  └─ RSA private key (opt)    └─ PIN (6-9 digits)                  │
+│                                                                    │
+│  DEPLOYMENT BINDING                                                │
+│  └─ Channel key (ties messages to a specific server/group)        │
+└────────────────────────────────────────────────────────────────────┘
 
-BREAKING CHANGES in v3.2.0:
-- Removed date dependency from key derivation
-- Renamed day_phrase → passphrase (no daily rotation needed)
+All factors get mixed together through Argon2id (memory-hard KDF) to derive
+the actual encryption key. Miss any factor = wrong key = garbage output.
+
+Encryption: AES-256-GCM (authenticated encryption - tamper = detection)
+KDF: Argon2id (256MB RAM, 4 iterations) or PBKDF2 fallback (600K iterations)
+
+v4.0.0: Added channel key for server/group isolation
+v3.2.0: Removed date dependency (was cute but annoying in practice)
 """
 
 import hashlib
@@ -98,25 +106,38 @@ def _resolve_channel_key(channel_key: str | bool | None) -> bytes | None:
 # =============================================================================
 # CORE CRYPTO FUNCTIONS
 # =============================================================================
+#
+# The "reference photo as a key" concept is one of Stegasoo's unique features.
+# Most steganography tools just use a password. We add the photo as a
+# "something you have" factor - like a hardware token, but it's a cat picture.
 
 
 def hash_photo(image_data: bytes) -> bytes:
     """
     Compute deterministic hash of photo pixel content.
 
-    This normalizes the image to RGB and hashes the raw pixel data,
-    making it resistant to metadata changes.
+    This is the magic sauce that turns your cat photo into a cryptographic key.
+
+    Why pixels and not the file hash?
+    - File metadata changes (EXIF stripped, resaved) = different file hash
+    - But pixel content stays the same
+    - We hash the RGB values directly, so format conversions don't matter
+
+    The double-hash with prefix is belt-and-suspenders mixing. Probably
+    overkill, but hey, it's crypto - paranoia is a feature.
 
     Args:
-        image_data: Raw image file bytes
+        image_data: Raw image file bytes (any format PIL can read)
 
     Returns:
-        32-byte SHA-256 hash
+        32-byte SHA-256 hash of pixel content
     """
+    # Convert to RGB to normalize (RGBA, grayscale, etc. all become RGB)
     img: Image.Image = Image.open(io.BytesIO(image_data)).convert("RGB")
     pixels = img.tobytes()
 
-    # Double-hash with prefix for additional mixing
+    # Double-hash: SHA256(SHA256(pixels) + first 1KB of pixels)
+    # The prefix adds image-specific data to prevent length-extension shenanigans
     h = hashlib.sha256(pixels).digest()
     h = hashlib.sha256(h + pixels[:1024]).digest()
     return h
@@ -133,20 +154,38 @@ def derive_hybrid_key(
     """
     Derive encryption key from multiple factors.
 
-    Combines:
-    - Photo hash (something you have)
-    - Passphrase (something you know)
-    - PIN (something you know, static)
-    - RSA key (something you have)
-    - Channel key (deployment/group binding)
-    - Salt (random per message)
+    This is the heart of Stegasoo's security model. We take all the things
+    you need to prove you're authorized (photo, passphrase, PIN, etc.) and
+    blend them together into one 32-byte key.
 
-    Uses Argon2id if available, falls back to PBKDF2.
+    The flow:
+    ┌─────────────┐   ┌─────────────┐   ┌─────────────┐
+    │ Photo hash  │ + │ passphrase  │ + │ PIN + RSA   │ + salt
+    └─────────────┘   └─────────────┘   └─────────────┘
+           │                 │                 │
+           └────────────────┴────────────────┘
+                             │
+                             ▼
+                    ┌─────────────────┐
+                    │    Argon2id     │  <- Memory-hard KDF
+                    │   256MB / 4 iter │  <- Makes brute force expensive
+                    └─────────────────┘
+                             │
+                             ▼
+                      32-byte AES key
+
+    Why Argon2id?
+    - Memory-hard: attackers can't just throw GPUs at it
+    - 256MB RAM per attempt = expensive at scale
+    - Winner of the Password Hashing Competition (2015)
+    - "id" variant resists both side-channel and GPU attacks
+
+    Fallback: PBKDF2-SHA512 with 600K iterations (for systems without argon2)
 
     Args:
         photo_data: Reference photo bytes
-        passphrase: Shared passphrase (recommend 4+ words)
-        salt: Random salt for this message
+        passphrase: Shared passphrase (recommend 4+ words from BIP-39)
+        salt: Random salt for this message (32 bytes)
         pin: Optional static PIN
         rsa_key_data: Optional RSA key bytes
         channel_key: Channel key parameter:
@@ -155,7 +194,7 @@ def derive_hybrid_key(
             - "" or False: No channel key (public mode)
 
     Returns:
-        32-byte derived key
+        32-byte derived key (ready for AES-256)
 
     Raises:
         KeyDerivationError: If key derivation fails
@@ -163,31 +202,36 @@ def derive_hybrid_key(
     try:
         photo_hash = hash_photo(photo_data)
 
-        # Resolve channel key
+        # Resolve channel key (server-specific binding)
         channel_hash = _resolve_channel_key(channel_key)
 
-        # Build key material
+        # Build key material by concatenating all factors
+        # Passphrase is lowercased to be forgiving of case differences
         key_material = photo_hash + passphrase.lower().encode() + pin.encode() + salt
 
-        # Add RSA key hash if provided
+        # Add RSA key hash if provided (another "something you have")
         if rsa_key_data:
             key_material += hashlib.sha256(rsa_key_data).digest()
 
-        # Add channel key hash if configured (v4.0.0)
+        # Add channel key hash if configured (v4.0.0 - deployment binding)
         if channel_hash:
             key_material += channel_hash
 
+        # Run it all through the KDF
         if HAS_ARGON2:
+            # Argon2id: the good stuff
             key = hash_secret_raw(
                 secret=key_material,
                 salt=salt[:32],
-                time_cost=ARGON2_TIME_COST,
-                memory_cost=ARGON2_MEMORY_COST,
-                parallelism=ARGON2_PARALLELISM,
+                time_cost=ARGON2_TIME_COST,      # 4 iterations
+                memory_cost=ARGON2_MEMORY_COST,  # 256 MB RAM
+                parallelism=ARGON2_PARALLELISM,  # 4 threads
                 hash_len=32,
-                type=Type.ID,
+                type=Type.ID,  # Hybrid mode: resists side-channel AND GPU attacks
             )
         else:
+            # PBKDF2 fallback for systems without argon2-cffi
+            # 600K iterations is slow but not memory-hard
             kdf = PBKDF2HMAC(
                 algorithm=hashes.SHA512(),
                 length=32,
@@ -347,9 +391,12 @@ def _unpack_payload(data: bytes) -> DecodeResult:
 # =============================================================================
 # HEADER FLAGS (v4.0.0)
 # =============================================================================
+#
+# The flags byte tells us about the message without decrypting it.
+# Currently just one flag, but the byte gives us room for 8.
 
-# Header flag bits
-FLAG_CHANNEL_KEY = 0x01  # Set if encoded with a channel key
+FLAG_CHANNEL_KEY = 0x01  # Bit 0: Message was encoded with a channel key
+# Future flags could include: compression, file attachment, etc.
 
 
 def encrypt_message(
@@ -361,33 +408,40 @@ def encrypt_message(
     channel_key: str | bool | None = None,
 ) -> bytes:
     """
-    Encrypt message or file using AES-256-GCM with hybrid key derivation.
+    Encrypt message or file using AES-256-GCM.
 
-    Message format (v4.0.0 - with channel key support):
-    - Magic header (4 bytes)
-    - Version (1 byte) = 5
-    - Flags (1 byte) - indicates if channel key was used
-    - Salt (32 bytes)
-    - IV (12 bytes)
-    - Auth tag (16 bytes)
-    - Ciphertext (variable, padded)
+    This is where plaintext becomes ciphertext. We use AES-256-GCM which is:
+    - AES: The standard, used by everyone from banks to governments
+    - 256-bit key: Enough entropy to survive until the heat death of the universe
+    - GCM mode: Authenticated encryption - if anyone tampers, decryption fails
+
+    The output format (v4.0.0):
+    ┌──────────────────────────────────────────────────────────────────────┐
+    │ \x89ST3 │ 05 │ flags │  salt (32B)  │  iv (12B)  │  tag (16B)  │ ··· │
+    │  magic  │ver │       │              │            │             │cipher│
+    └──────────────────────────────────────────────────────────────────────┘
+
+    Why the random padding at the end?
+    - Message length can reveal information (traffic analysis)
+    - We add 64-319 random bytes and round to 256-byte boundary
+    - All messages look roughly the same size
 
     Args:
         message: Message string, raw bytes, or FilePayload to encrypt
-        photo_data: Reference photo bytes
-        passphrase: Shared passphrase (recommend 4+ words for good entropy)
-        pin: Optional static PIN
-        rsa_key_data: Optional RSA key bytes
+        photo_data: Reference photo bytes (your "key photo")
+        passphrase: Shared passphrase (recommend 4+ words from BIP-39)
+        pin: Optional static PIN for additional security
+        rsa_key_data: Optional RSA key bytes (another "something you have")
         channel_key: Channel key parameter:
-            - None or "auto": Use configured key
+            - None or "auto": Use server's configured key
             - str: Use this specific key
             - "" or False: No channel key (public mode)
 
     Returns:
-        Encrypted message bytes
+        Encrypted message bytes ready for embedding
 
     Raises:
-        EncryptionError: If encryption fails
+        EncryptionError: If encryption fails (shouldn't happen with valid inputs)
     """
     try:
         salt = secrets.token_bytes(SALT_SIZE)