libdeflate VS Zpng

zune-inflate is a port of libdeflate to safe Rust.

> The QOI benchmarks shows it only lagging a small bit behind PNG in compression ratio, while performing much faster (multiples) in both encoding and decoding.

Presumably that’s with stock libpng, which uses zlib. I wonder if anyone tried patching it to use the substantially faster (on x86) libdeflate[1] instead? It doesn’t do streaming, but you shouldn’t really need it for PNG textures.

[1] https://github.com/ebiggers/libdeflate

Eric biggers libdeflate https://github.com/ebiggers/libdeflate/blob/master/lib/deflate_decompress.c

Note that libdeflate has used essentially the same method since 2016 (https://github.com/ebiggers/libdeflate/blob/v0.4/lib/adler32...), though I recently switched it to use a slightly different method (https://github.com/ebiggers/libdeflate/blob/v1.12/lib/x86/ad...) that performs more consistently across different families of x86 CPUs.

Going away from Zlib proper but staying with its format, there’s libdeflate[1], an implementation that’s substantially faster on modern machines but can’t stream, and of course Zopfli[2], a glacially slow compressor that’s somewhat better (and occasionally much more so).

[1] https://github.com/ebiggers/libdeflate

[2] https://github.com/google/zopfli

> You'd probably get even better results by using PNG's filters instead of QOI

Did anybody ever try this? It would be quite interesting and does not seem too difficult.

The only thing I could find is https://github.com/catid/Zpng which does not use the normal PNG filtering.

Also, Chris Taylor published an experimental PNG library with Zstd hardwired in.

- I feel like the benchmark suite is lacking. For better overview you probably should include libpng results with max compression level and lowest compression level. Lossless modes of AVIF and WEBP would be nice. (also could throw similar project to yours like https://github.com/catid/Zpng) Not saying the benchmark is bad, but IMHO doesn't paint the full picture. From quick test I got significantly better compression on libpng, ofc in expense of time, but you didn't optimize it for speed either. So we have some results, but they are not really representative imho.