1. 30 Oct, 2016 5 commits
  2. 29 Oct, 2016 1 commit
    • Thomas's avatar
      Add EC_ADAPT experiment for symbol-adaptive entropy coding. · 9ac5508f
      Thomas authored
      This experiment performs symbol-by-symbol statistics
      adaptation for non-binary symbols. It requires DAALA_EC or
      RANS and ANS to be enabled. The adaptation is currently
      based on a simple recursive filter and is taken from
      Daala. It has an adaptation rate dependent on alphabet size,
      taken from Daala. It applies wherever non-binary symbols
      are encoded using Cumulative Probability Functions rather
      than trees.
      
      Where symbols are adapted, forward updates in the compressed
      header are removed.
      
      In the case of RANS coefficient token values are adapted,
      with the exception of the zero token which remains a
      binary symbol. In the case of DAALA_EC other values
      such as inter and intra modes are adapted as CDFs are
      provided in those cases.
      
      The experiment is configured with:
      
      ./configure --enable-experimental --enable-daala-ec --enable-ec-adapt
      
      or
      
      ./configure --enable-experimental --enable-ans --enable-rans \
          --enable-ec-adapt
      
      EC_ADAPT is not currently compatible with tiles.
      
      BDR results on Objective-1-fast give a small loss:
      
      PSNR YCbCr:      0.51%      0.49%      0.48%
      PSNRHVS:      0.50%
      SSIM:      0.50%
      MSSSIM:      0.51%
      CIEDE2000:      0.50%
      
      Change-Id: I3888718e42616f3fd87144de7f125228446ac984
      9ac5508f
  3. 28 Oct, 2016 30 commits
  4. 27 Oct, 2016 4 commits