1. 15 Jul, 2013 2 commits
    • Jingning Han's avatar
      Skip duplicate block encoding in the rd loop · faff6ed0
      Jingning Han authored
      This speed feature allows the encoder to largely remove the spatial
      dependency between blocks inside a 64x64 superblock, thereby removing
      the need to repeatedly encode superblocks per partition type in the
      rate-distortion optimization loop.
      
      A major challenge lies in the intra modes tested in the rate-distortion
      optimization loop. The subsequent blocks do not have access to the
      reconstructed boundary pixels without the intermediate coding steps.
      This was resolved by using the original pixels for intra prediction
      in the rd loop, followed by an appropriately designed distortion
      modeling on the quantization parameters. Experiments also suggested
      that the performance impact is more discernible at lower bit-rate/psnr
      settings. Hence a quantizer dependent threshold is applied to deactivate
      skip of block coding.
      
      For bus_cif at 2000 kbps,
      speed 0: runtime 269854ms -> 237774ms (12% speed-up) at 0.05dB
               performance loss.
      
      speed 1: runtime 65312ms  -> 61536ms, (7% speed-up) at 0.04dB
               performance loss.
      
      This operation is currently turned on in settings of speed 1.
      
      Change-Id: Ib689741dfff8dd38365d8c1b92860a3e176f56ec
      faff6ed0
    • Dmitry Kovalev's avatar
  2. 13 Jul, 2013 3 commits
  3. 12 Jul, 2013 24 commits
  4. 11 Jul, 2013 11 commits