A fast deflate implementation.
This crate contains an optimized implementation of the deflate algorithm tuned to compress PNG images. It is compatible with standard zlib, but make a bunch of simplifying assumptions that drastically improve encoding performance:
- Exactly one block per deflate stream.
- No distance codes except for run length encoding of zeros.
- A single fixed huffman tree trained on a large corpus of PNG images.
- All huffman codes are <= 12 bits.
It also contains a fast decompressor that supports arbitrary zlib streams but does especially well on streams that meet the above assumptions.
The algorithms in this crate take inspiration from multiple sources: