DaalaTodo

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Simple Things

  • Overflow checking for allocations in od_state_ref_imgs_init().
  • Implement Bugzilla for Daala users to report bugs and enhancements.

Tuning

  • Quantization matrix
    • Rate-dependent QMs
  • Beta (activity masking)
  • PVQ RDO
  • Better MV cost estimates
  • Better MC distortion metrics (SATD, some MSE/SATD hybrid, no-ref-aware, maybe table driven Theora-style, etc.)
  • Better MV split flag rate estimates
  • Does the 8-pixel MV offset influence quality in any way?
  • Tuning for new lapping
    • quantization matrices
    • lambda
    • Haar DC

Known Broken/Suboptimal

  • Block size decision
    • Never tuned on inter
    • Not considering chroma
  • Investigate bias introduced by coefficient scaling
  • Take into account scaling differences from lapping on variable block size
    • Including Haar DC
  • Finish "skip higher bands" flags
  • Re-train zig-zags (particularly on inter)
  • Implement RDO for "skip_rest" decisions.
  • Better RDO rates for gain/theta/noref
  • Don't code blocks that are outside the image

New Work

  • Motion vector "mask" based on previous frame
  • Use coeff magnitude correlation for modelling
  • Per SB/MB/block/something quantizer changes
  • Variable Framerate support
  • Dynamic frame size changes (without keyframes)
  • Land paint-based deringing
  • SPIHT as k-tokenizer
  • MV prediction clustering
  • Special case for K=2
  • Train Laplace tables

Entropy Coding

  • Make the Laplace vector encoder (aka k-tokenizer) faster
  • Add "skip-all remaining bands" flag
  • Better encoding of the CfL sign
  • Add SIMD to the decoder search

Minor things

  • Code quantizers on a log scale

Visualization

  • Add ability to display decoder side information to player_example
    • Block size split decision
    • Cost in bits per block (use log scale)
    • No-ref and skip flags
    • Mode information (if we signal intra)
    • Motion vectors
    • Display prediction residual

Bit-stream work (no expected quality improvement)

  • Need a bugzilla instance for issue tracking
  • Re-order bitstream (e.g., don't code all MVs at the front, etc.)

AreWeCompressedYet

Wiki page: AreWeCompressedYet

Website: https://arewecompressedyet.com

Bug tracker: https://github.com/tdaede/awcy/issues

  • Huge batch run of all versions of Daala
  • Look at rd_tool options and improve
  • Add realtime constraint options for x265