QOI Image Codec Workbench

How to use QOI Image Codec Workbench

Decode a bounded QOI image to PNG or encode a supported static raster as a separate QOI file locally. The QOI codec handles indexed pixels, channel differences, luma differences, runs and full RGB/RGBA chunks in an isolated Worker. Dimensions and file boundaries are checked before pixel allocation.

1. Provide local source image.
2. Choose the supported mode and run the tool. Review its assumptions and any reported errors.
3. Copy the result or download a separate output; reset to clear the current form.

Good to know

• QOI input up to 12 MiB; static raster input up to 8 MiB. Every source is limited to 2,000,000 pixels and 4,096 pixels per side before native decoding or pixel allocation.
• Raster input uses the strict static subset: validated non-animated PNG chunks, single-frame baseline JPEG or simple non-animated WebP. Progressive JPEG, APNG, VP8X, embedded compressed metadata and arbitrary SVG are refused. A JPEG whose native EXIF orientation changes the declared dimensions is also refused.
• Worker startup and module preparation have a separate 10-second deadline; codec computation has a 2-second deadline. QOI requires an exact end marker, one image and no unused/trailing chunk bytes.
• QOI linear RGB is converted to an sRGB PNG preview. Raster encoding stores browser-provided 8-bit sRGB RGBA samples. Browser color conversion, premultiplication and transparent hidden-color behavior can change samples across PNG/raster conversion; this is not color-managed archival preservation.
• Inputs are processed on this device and are not automatically saved or uploaded.