jxl-oxide v0.5.1

Version 0.5.0 and 0.5.1 of jxl-oxide (and version 0.3.0 of jxl-oxide-cli) contains new decoding interface, a decent amount of performance boost, and various bugfixes.

Decoding interface changes

Push-based input API

Previously, the decoder got its data in pull-based way: something that implements std::io::Read is given, the decoder reads ("pulls") bytes from it, try to decode those, and repeat. Now the internal API has been rewritten to push-based, meaning that byte slices are pushed into the decoder explicitly by users. The main reason of this rewrite is to optimize some internal routines of bitstream reader, but it has some (nice) side effects:

• It's easier to suspend decoding somewhere in a bitstream.
• The new API can accept async byte streams easily.

jxl-oxide provides convenience methods that deal with std::io::Read types.

Thread-safe renderer

Renderer is now thread-safe! Frames can be simultaneously rendered in multiple threads as long as they are already decoded (frames are decoded when its bytes are pushed to the decoder).

Performance boost

Multithreaded rendering

The renderer itself has also introduced parallelism in various places, including multithreaded filters and group¹ decoding. jxl-oxide uses Rayon for thread pool implementation. If you don't need multithreading support, rayon feature can be turned off at compile time to completely disable multithreaded rendering (it will stay thread-safe though).

More SIMD routines

• SIMD version of edge-preserving filter is added.
• NEON specific SIMD routines are added for aarch64 (but not armv7), both autovectorized and handwritten.

CLI utilities

• jxl-info introduces new flags, --all-frames and --with-offset.

• jxl-dec introduces new flag -j (--num-threads) which controls the number of threads in thread pool.

• jxl-dec allows partial image files, and it will try decoding as much as possible. With some shell scripting, one can make an interesting progressive decoding animation:

  starrail-d1-e7-pdc.mp4

Other changes

• Optimize for special modular images by @tirr-c in #82
• jxl-color: Fast color transforms by @tirr-c in #93
• Rewrite bitstream reader, enable partial decoding by @tirr-c in #96
• Fuzzing via honggfuzz by @Nereuxofficial in #101
• Rewrite Modular buffer management by @tirr-c in #108
• Add license symlinks to individual crates by @kalev in #111

New Contributors

• @Nereuxofficial made their first contribution in #101
• @kalev made their first contribution in #111

Full Changelog: 0.4.0...0.5.1

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1. A group is a tile in JPEG XL frame that serves as a unit of decoding. ↩