seedgou

Oh! You mean the scanning speed. I thought you was talking about the original PDF preview. For now, scanning is using emscriptened ImageMagick Wasm. Due to the translation from C++ to Wasm, the scanning speed is very slow. Maybe re-writing blur, rotate and noise algorithm will speed up the scanning.

The rendering logic is in `src/utils/pdf/renderPage.ts` and has only 26 lines.

The site's logic is nearly identical to this gist: use ImageMagick to do the rotate, noise, etc.

Good idea! A random distribution on rotation seems a more user-friendly way instead of setting 10 rotation values.

I didn't manipulate the data in pixel level. Maybe because I render PDF in 2x which causes 4x more pixels?

There's an example PDF after clicking "START SCANNING" button. Maybe add more real-world examples.

Use PDF.js and magica to do the rendering and processing. You could see the credits in GitHub repo page.