1. 15 Dec, 2015 1 commit
    • Debargha Mukherjee's avatar
      Replace DST1 in ext_tx experiment with DST2 · 49d9730f
      Debargha Mukherjee authored
      The DST2 is implemented by input alternate sign-flip, followed
      by DCT, followed by output reversal.
      Results are roughly the same, but it should be easier to optimize
      the DST2.
      [Interestingly a mtrix multuiply implementation is about 0.1%
      better].
      
      Change-Id: If9ae5fdba87767fb0e6c163a62b77ee66a8d3afc
      49d9730f
  2. 11 Dec, 2015 7 commits
  3. 10 Dec, 2015 16 commits
  4. 09 Dec, 2015 12 commits
  5. 08 Dec, 2015 4 commits
    • Debargha Mukherjee's avatar
    • Hui Su's avatar
      cdffec73
    • paulwilkins's avatar
      Changes to exhaustive motion search. · 4e692bbe
      paulwilkins authored
      This change has been imported from VP9 and
      alters the nature and use of exhaustive motion search.
      
      Firstly any exhaustive search is preceded by a normal step search.
      The exhaustive search is only carried out if the distortion resulting
      from the step search is above a threshold value.
      
      Secondly the simple +/- 64 exhaustive search is replaced by a
      multi stage mesh based search where each stage has a range
      and step/interval size. Subsequent stages use the best position from
      the previous stage as the center of the search but use a reduced range
      and interval size.
      
      For example:
        stage 1: Range +/- 64 interval 4
        stage 2: Range +/- 32 interval 2
        stage 3: Range +/- 15 interval 1
      
      This process, especially when it follows on from a normal step
      search, has shown itself to be almost as effective as a full range
      exhaustive search with step 1 but greatly lowers the computational
      complexity such that it can be used in some cases for speeds 0-2.
      
      This patch also removes a double exhaustive search for sub 8x8 blocks
      which also contained  a bug (the two searches used different distortion
      metrics).
      
      For best quality in my test animation sequence this patch has almost
      no impact on quality but improves encode speed by more than 5X.
      
      Restricted use in good quality speeds 0-2 yields significant quality gains
      on the animation test of 0.2 - 0.5 db with only a small impact on encode
      speed. On most natural video clips, however, where the step search
      is performing well, the quality gain and speed impact are small.
      
      Change-Id: Iac24152ae239f42a246f39ee5f00fe62d193cb98
      4e692bbe
    • Peter de Rivaz's avatar
      Fix for crash when using high bitdepth and var-tx · 22850493
      Peter de Rivaz authored
      Change-Id: Ide48fa4312f7828f99290f7a2be878f5673fa716
      22850493