• Tero Rintaluoma's avatar
    Avoid division in intra prediction · 56e6c66b
    Tero Rintaluoma authored
    - Using multiplication and shifting instead of division in
      intra prediction.
    - Maximum absolute difference is 1 for division statements
      in d45, d27, d63 prediction modes. However, errors can
      cumulate for large block sizes when using already predicted
      values.
    - Maximum number of non-matching result values in loops using
      division are:
      4x4        0/16
      8x8        0/64
      16x16     10/256
      32x32     13/1024
      64x64    122/4096
    
      Overall PSNR
      derf:     0.005
      yt:      -0.022
      std-hd:   0.021
      hd:      -0.006
    
    Change-Id: I3979a02eb6351636442c1af1e23d6c4e6ec1d01d
    56e6c66b
vp9_reconintra.c 28.1 KB