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Simple Things

  • Overflow checking for allocations in od_state_ref_imgs_init().


  • Quantization matrix
    • Rate-dependent QMs
  • Beta (activity masking)
  • 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

Known broken/suboptimal

  • Block size decision
    • Never tuned on inter
    • Not considering chroma
  • Code quantizers on a log scale
  • Re-order bitstream (e.g., don't code all MVs at the front, etc.)
  • Investigate bias introduced by coefficient scaling
  • Take into account scaling differences from lapping on variable block size
    • Including Haar DC
  • Need "skip higher bands" flag

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

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


  • 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


  • Need a bugzilla instance for issue tracking


Website: AreWeCompressedYet
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