# InkStudio (墨印工坊)

> InkStudio is a 100% client-side handwritten signature, crimson company seal, and brush calligraphy transparent alpha extraction and Bézier SVG vectorization studio powered by a zero-dependency Rust + WebAssembly engine (81 KB), operating over HTTPS with 0 bytes of user images uploaded.

## Key Capabilities

- **4 Specialized Extraction Modes**: Handwritten Signature & Pen Mode, Red Cinnabar Seal Mode, Brush Calligraphy Flying-White Mode, and Dual Signature + Seal Mode.
- **O(1) Illumination Shadow Stripping**: Dual-scale 2D Summed-Area Table (Integral Image) local background envelope estimation eliminates uneven smartphone shadows and aged yellow paper tints.
- **Overlapping Contract Text Inpainting**: Detects dark achromatic contract text crossing crimson seals and heals gaps via iterative 8-neighbor directional morphological diffusion (1–12 px radius).
- **Notebook Ruled & Calligraphy Grid Line Removal**: Strips blue/green/gray horizontal and vertical lines via chromaticity excess and run-length projection while protecting handwriting stroke crossings.
- **Exact 2D Euclidean SDF Stroke Morphing**: Felzenszwalb-Huttenlocher O(N) parabola-envelope Euclidean Distance Transform shifts stroke weight smoothly from -2.5 px (thinning) to +4.5 px (boldening) with 0.85 px anti-aliasing.
- **One-Click Semantic SVG Vectorizer**: Boundary contour tracing + Ramer-Douglas-Peucker polyline simplification + quadratic Bézier curve fitting in Rust Wasm.

## Canonical Entry Points (4 Languages)

- [Simplified Chinese Workbench (zh-Hans)](https://ink.llmland.io/zh-Hans/) · [常见问题与算法原理 (FAQ)](https://ink.llmland.io/zh-Hans/faq/)
- [Traditional Chinese Workbench (zh-Hant)](https://ink.llmland.io/zh-Hant/) · [常見問題與演算法原理 (FAQ)](https://ink.llmland.io/zh-Hant/faq/)
- [English Workbench (en)](https://ink.llmland.io/en/) · [FAQ & Optical Unmixing Algorithms](https://ink.llmland.io/en/faq/)
- [Japanese Workbench (ja)](https://ink.llmland.io/ja/) · [よくある質問と光学分離アルゴリズム原理 (FAQ)](https://ink.llmland.io/ja/faq/)

## Agent & Machine-Readable Endpoints

- [Full Technical Specification (/llms-full.txt)](https://ink.llmland.io/llms-full.txt)
- [Standalone FAQ & Algorithm Guide (/faq/)](https://ink.llmland.io/faq/)
- [XML Sitemap (/sitemap.xml)](https://ink.llmland.io/sitemap.xml)
- [AI Crawler Policy (/robots.txt)](https://ink.llmland.io/robots.txt)