feat: SVG support with limitations

Author: bindiego

Cargo.lock

@@ -8,9 +8,13 @@ description = "Invisible robust watermarking system for multimedia files"
 clap = { version = "4", features = ["derive"] }
 image = "0.25"
 imageproc = "0.26.1"
+num-complex = "0.4.6"
 rand = "0.8"
 rand_chacha = "0.3"
+rustfft = "6.4.1"
 sha2 = "0.10"
+tiny-skia-path = "0.12.0"
+usvg = "0.47.0"
 
 [dev-dependencies]
 tempfile = "3"

Cargo.toml

@@ -18,8 +18,9 @@ build: debug release ## Build both debug and release
 test-unit: ## Run unit tests (debug)
 	cargo test --lib
 
-test-integration: ## Run integration tests with real images (debug)
+test-integration: ## Run integration tests with real images and SVGs (debug)
 	cargo test --test picture_tests
+	cargo test --test svg_tests
 
 test: test-unit test-integration ## Run all tests (debug)
 

Makefile

@@ -2,163 +2,107 @@
 
 [![Build](https://github.com/infinilabs/infinishield/actions/workflows/build.yml/badge.svg)](https://github.com/infinilabs/infinishield/actions/workflows/build.yml)
 
-A command-line tool for embedding invisible, robust watermarks into images with cropping resistance.
+A command-line tool for embedding invisible watermarks into images and SVG files.
 
-## How It Works
+## What It Does
 
-infinishield embeds text messages (e.g., copyright notices, user IDs) into images in a way that is:
+infinishield hides a short text message (e.g., a copyright notice) inside an image or SVG file. The watermark is:
 
-- **Invisible** — changes are imperceptible to the human eye
-- **Blind** — extraction does not require the original image
-- **Password-protected** — only someone with the correct password can extract the watermark
-- **Cropping-resistant** — watermark survives partial image cropping (feature-point mode)
+- **Invisible** — no visible changes to the file
+- **Password-protected** — only someone with the password can extract it
+- **Cropping-resistant** — survives partial image cropping (for short messages)
 
-### Dual-Mode Embedding
+## Supported Formats
 
-infinishield automatically selects the best embedding mode based on image content and message length:
-
-**Feature-Point Mode** (default for short messages ≤ 7 bytes):
-- Detects stable keypoints using oriented FAST corners
-- Embeds the same watermark at every keypoint via spread spectrum
-- Survives cropping: majority vote across surviving keypoints recovers the message
-- Max message: 7 bytes
-
-**Global DWT Mode** (fallback for longer messages):
-- 1-level Haar wavelet transform on the full image
-- Spread spectrum embedding in the HL detail subband
-- Higher capacity but no cropping resistance
-- Max message depends on image size (e.g., ~40 bytes for 1024×1024)
-
-### Auto Intensity
-
-When `--intensity` is omitted, infinishield selects optimal strength based on image size:
-
-| Image Size | Auto Intensity |
-|-----------|:--------------:|
-| < 0.5 MP | 7 |
-| 0.5–2 MP | 5 |
-| 2–8 MP | 4 |
-| > 8 MP | 3 |
-
-Smaller images need higher intensity to survive u8 quantization; larger images can use lower intensity for better invisibility.
+| Format | Status |
+|--------|--------|
+| JPEG, PNG, WebP, BMP, TIFF, GIF | Supported |
+| SVG | Supported |
+| MP4, WebM (video) | Planned |
 
 ## Building
 
-Requires Rust 1.70+ (no system libraries needed — pure Rust implementation).
+Requires [Rust](https://rustup.rs/) 1.70+.
 
 ```bash
-cargo build --release
+make release    # Build optimized binary
 ```
 
-The binary will be at `target/release/infinishield`.
+The binary will be at `target/release/infinishield`. Run `make help` to see all available commands.
 
 ## Usage
 
 ### Embed a Watermark
 
 ```bash
-# Minimal — uses default message, password, and auto intensity
-infinishield embed -i source.jpg -o output.png
-
-# Full — all parameters explicit
-infinishield embed \
-  -i source.jpg \
-  -m "Infini" \
-  -p "d1ng0" \
-  -o output.png \
-  --intensity 5
-
-# Dry run — preview without writing output
-infinishield embed -i source.jpg -o output.png --dry-run
-```
+# Simplest — embeds default message "Infini" with default password
+infinishield embed -i photo.jpg -o watermarked.png
 
-| Flag | Required | Default | Description |
-|------|----------|---------|-------------|
-| `-i, --input` | yes | — | Input image path (PNG, JPEG, WebP, BMP, TIFF, GIF) |
-| `-o, --output` | yes | — | Output image path (PNG recommended for lossless) |
-| `-m, --message` | no | `"Infini"` | Message to embed as watermark |
-| `-p, --password` | no | `"d1ng0"` | Password for scrambling and verification |
-| `--intensity` | no | auto | Embedding strength (1-10). Auto-selected from image size if omitted |
-| `--dry-run` | no | — | Preview embedding info without writing the output file |
+# Custom message and password
+infinishield embed -i photo.jpg -m "MyMark" -p "secret" -o watermarked.png
 
-**Output format:** Any format supported by the `image` crate (PNG, JPEG, WebP, BMP, TIFF, GIF). PNG is recommended because it is lossless. A warning is printed if the output format is lossy (JPEG, WebP, GIF) as compression may degrade the watermark.
+# SVG file
+infinishield embed -i logo.svg -o logo_wm.svg -m "Hi"
 
-Example output:
-```
-[成功] 水印已嵌入。
-[信息] 模式: feature-point | 消息: "Infini" (6 字节) | 强度: 7 | 抗压缩率: 中
-[信息] 图像: 700x496 | 特征点: 200 | 容量上限: 7 字节
-[信息] 输出: output.png
+# Preview without writing (dry run)
+infinishield embed -i photo.jpg -o out.png --dry-run
 ```
 
-Dry-run output:
-```
-[模拟] 水印嵌入预览 (未生成文件):
-[信息] 模式: feature-point | 消息: "Infini" (6 字节) | 强度: 3 | 抗压缩率: 低
-[信息] 图像: 3840x2160 | 特征点: 200 | 容量上限: 7 字节
-[信息] 输出: output.png
-```
+| Option | Required | Default | Description |
+|--------|----------|---------|-------------|
+| `-i` | yes | — | Input file |
+| `-o` | yes | — | Output file (PNG recommended for images) |
+| `-m` | no | `"Infini"` | Message to hide (max 7 bytes for cropping resistance) |
+| `-p` | no | `"d1ng0"` | Password |
+| `--intensity` | no | auto | Embedding strength (1-10, images only) |
+| `--dry-run` | no | — | Show info without writing output |
 
-### Verify / Extract a Watermark
+### Verify / Extract
 
 ```bash
-# Minimal — uses default password
-infinishield verify -i suspicious_image.jpg
+# Check if a file contains a watermark
+infinishield verify -i watermarked.png
 
-# With explicit password
-infinishield verify -i suspicious_image.jpg -p "d1ng0"
+# With a specific password
+infinishield verify -i watermarked.png -p "secret"
 ```
 
-| Flag | Required | Default | Description |
-|------|----------|---------|-------------|
-| `-i, --input` | yes | — | Input image path to verify |
-| `-p, --password` | no | `"d1ng0"` | Password used during embedding |
-
-Output on success:
+Example output:
 ```
-[分析中] 正在执行频域扫描...
 [验证结果] 匹配成功！(置信度: 99.3%)
 [提取内容] "Infini"
 ```
 
-Output on failure (no watermark or wrong password):
-```
-[验证结果] 失败。未检测到有效水印，或密码错误。
-```
-
-## Running Tests
+### Help
 
 ```bash
-make test-unit         # Unit tests (debug)
-make test-integration  # Integration tests with real images (debug)
-make test              # All tests (debug)
-make test-release      # All tests (release)
-make sanity            # Full check: fmt + lint + build + all tests (debug & release)
+infinishield              # Show full help
+infinishield --version    # Show version
 ```
 
-## Current Limitations
+## Limitations
 
-- **Short messages only for cropping resistance** — messages up to 7 bytes (e.g., "Infini") survive cropping. Longer messages (e.g., "Copyright: InfiniLabs") still work but lose cropping protection.
-- **No rotation or scaling resistance** — the watermark survives cropping and compression, but not if the image is rotated or resized.
-- **Raster images only** — JPEG, PNG, WebP, BMP, TIFF, GIF. SVG and video support is planned.
-- **Lossy output degrades watermark** — saving as JPEG or WebP compresses the watermark. PNG or BMP output is recommended. A warning is printed for lossy formats.
+**Images:**
+- Messages up to 7 bytes survive cropping. Longer messages work but lose cropping protection.
+- Rotation and resizing are not supported — only cropping and compression.
+- Saving as JPEG degrades the watermark. Use PNG for best results.
 
-## Project Structure
+**SVG:**
+- Only works on SVGs with complex paths. Simple shapes (rectangles, circles) have too few coordinates.
+- Message capacity is typically 2-7 bytes depending on SVG complexity.
+- SVG editors that reformat coordinates may destroy the watermark.
 
+**General:**
+- Video support is planned but not yet available.
+
+## Running Tests
+
+```bash
+make test       # All tests (debug)
+make sanity     # Full check: format + lint + build + all tests
+make clean      # Remove build artifacts and test outputs
 ```
-src/
-├── main.rs                # CLI entry point with format auto-detection
-├── lib.rs                 # Module declarations
-├── common/
-│   ├── engine.rs          # WatermarkEngine trait, EmbedResult, ExtractResult, EmbedInfo
-│   ├── ecc.rs             # Repetition-based error correction coding
-│   ├── scramble.rs        # ChaCha20-seeded Fisher-Yates bit permutation
-│   ├── password.rs        # SHA256 password hashing
-│   └── temp_input_for_inference.rs  # Managed inference buffer
-├── raster/
-│   ├── mod.rs             # RasterEngine: feature-point + global DWT dual mode
-│   ├── dwt.rs             # 1-level 2D Haar wavelet transform
-│   └── features.rs        # Oriented FAST keypoint detection + patch extraction
-├── vector/                # (Phase 2: SVG Fourier descriptor watermarking)
-└── video/                 # (Phase 3: Video temporal Harris + 3D-SVD)
-```
+
+## Documentation
+
+- [Technical Details](docs/tech_details.md) — architecture, algorithms, design decisions