v2.0.0-rc2

[gianni-rosato]

Note: this is a release candidate, not an official release. Expect the lack of polish that usually accompanies pre-release software, as well as this potentially incomplete release changelog.

PSY Updates

Var-boost

• Moved varboost delta-q adjusting code to happen before TPL, giving TPL the opportunity to work with more accurate superblock delta-q priors, and produce better final rdmult lambda values
  • Fixed rare cases of pulsing at high CRFs (>=40) and strengths (3-4)
  • 2% avg. bitrate reduction for comparable image quality
• Added an alternative boosting curve (--enable-alt-curve), with different variance/strength tradeoffs
• Refactored boost code so it internally works with native q-step ratios
• Removed legacy variance boosting method based on 64x64 values
  • Parameter --new-variance-octile -> --variance-octile

Excitingly, a var-boost mainline merge has been marked with the highest priority issue label by the mainline development team, so we may see this in mainline SVT-AV1 soon! Congrats @juliobbv! 🎉

Other

• Presets got faster, so in addition to Preset -2, we have an even slower Preset -3
• --sharpness now accepts negative values
• The SVT-AV1-PSY encoder now supports Dolby Vision encoding via Dolby Vision RPUs. To build with Dolby Vision support, install libdovi & pass --enable-libdovi to ./build.sh on macOS/Linux (or enable-libdovi to ./build.bat on Windows).

Mainline Updates

Encoder

• Improve the tradeoffs for the random access mode across presets:
• Speedup presets MR by ~100% and M0 to M8 by 3-28% while maintaining similar quality levels
• Improved the compression efficiency of presets M9-M13 by 1-4% (!2179)
• Simplified VBR multi-pass to use 2 passes to allow integration with ffmpeg
• Continued adding ARM optimizations for functions with c_only equivalent

Cleanup and bug fixes and documentation

• Various cleanups and functional bug fixes
• Update the documentation to reflect the rate control updates

Full Changelog: https://github.com/gianni-rosato/svt-av1-psy/commits/v2.0.0-rc2

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This discussion was created from the release v2.0.0-rc2.