# Scanner Studio

Open scanner-studio.html with the complete vendor folder present. All document processing stays in the browser. Camera availability depends on browser permission and a secure context; image uploads and mobile camera file selection are alternatives.

Import JPG, PNG, WebP or PDF pages. Adjust four corners or four edge handles with the magnifier, then choose measured, A4, Letter or square proportions. Perspective correction straightens the selected quadrilateral. Rotation supports 0.1 degree increments.

Twenty filters plus Original combine reusable colour, contrast, threshold, sharpening and lighting effects. White Paper Cleaner neutralises warm paper and reduces broad lighting variations while preserving dark text and saturated details. It cannot reconstruct obscured writing. Use the before/after slider to check results. The quality indicator is a basic resolution and sharpness heuristic, not a guarantee of readability.

Add text, dates, shapes, stamps, images or a drawn signature. Move, resize and rotate overlays; reorder, duplicate and delete pages with undo/redo. Signatures are visual marks, not cryptographic signatures.

Export the selected page as PNG/JPG or selected/all pages as PDF. Choose A4 or scan proportions and 150/300/600 DPI. Higher DPI increases pixel dimensions without recovering missing detail. Compression can reduce both JPEG quality and effective resolution. Estimated sizes are approximate; Prepare produces the actual encoded result for inspection and reports actual bytes and size change. PNG is lossless, so JPEG quality does not affect it. Print at Actual size/100% without browser headers or footers.

No upload-count, file-size, page or input-megapixel quotas. Large photos become appropriately sized working images automatically. Originals stay untouched. Processing remains local and depends on the device and browser.

Verified: 20 browser engine/export test groups, including corner homography, known A4 proportions, all filters, cleaner colour preservation, worker equivalence, compression, DPI metadata, overlays, PDF import and invalid-file rollback. A production download was independently parsed as a two-page A4 PDF (55,750 bytes). Physical cameras, printers and every mobile browser were not available for hardware testing.