tomato/README.md
2021-12-16 20:12:27 +01:00

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QOI - The “Quite OK Image” format for fast, lossless image compression

Single-file MIT licensed library for C/C++

See qoi.h for the documentation.

More info at https://phoboslab.org/log/2021/11/qoi-fast-lossless-image-compression

⚠️ 2021.11.30 the file format is not yet finalized. We're still working to fix some smaller issues. The final specification will be announced on 2021.12.20. Thanks for your patience! The WIP file format specification can be found in qoi.h

Why?

Compared to stb_image and stb_image_write QOI offers 20x-50x faster encoding, 3x-4x faster decoding and 20% better compression. It's also stupidly simple and fits in about 300 lines of C.

Example Usage

  • qoiconv.c converts between png <> qoi
  • qoibench.c a simple wrapper to benchmark stbi, libpng and qoi

Limitations

The QOI file format allows for huge images with up to 18 exa-pixels. A streaming en-/decoder can handle these with minimal RAM requirements, assuming there is enough storage space.

This particular implementation of QOI however is limited to images with a maximum size of 400 million pixels. It will safely refuse to en-/decode anything larger than that. This is not a streaming en-/decoder. It loads the whole image file into RAM before doing any work and is not extensively optimized for performance (but it's still very fast).

If this is a limitation for your use case, please look into any of the other implementations listed below.

Tools

Implementations of QOI

Packages

AUR - system-wide qoi.h, qoiconv and qoibench install as split packages.