27 lines
1.3 KiB
Markdown
27 lines
1.3 KiB
Markdown
# fdeflate
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[](https://crates.io/crates/fdeflate)
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[](https://docs.rs/fdeflate)
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[](https://github.com/image-rs/fdeflate/actions)
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A fast deflate implementation.
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This crate contains an optimized implementation of the deflate algorithm tuned to compress PNG
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images. It is compatible with standard zlib, but make a bunch of simplifying assumptions that
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drastically improve encoding performance:
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- Exactly one block per deflate stream.
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- No distance codes except for run length encoding of zeros.
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- A single fixed huffman tree trained on a large corpus of PNG images.
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- All huffman codes are <= 12 bits.
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It also contains a fast decompressor that supports arbitrary zlib streams but does especially
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well on streams that meet the above assumptions.
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### Inspiration
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The algorithms in this crate take inspiration from multiple sources:
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* [fpnge](https://github.com/veluca93/fpnge)
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* [zune-inflate](https://github.com/etemesi254/zune-image/tree/main/zune-inflate)
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* [RealTime Data Compression blog](https://fastcompression.blogspot.com/2015/10/huffman-revisited-part-4-multi-bytes.html)
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