/qoi

The “Quite OK Image Format” for fast, lossless image compression

Primary LanguageC

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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 and format specification.

More info at https://qoiformat.org

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 & Bindings of QOI

QOI Support in Other Software

Packages

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

Implementations not yet conforming to the final specification

These implementations are based on the pre-release version of QOI. Resulting files are not compatible with the current version.