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• Revision d36852b702 : Add encoding option —static-thresh This option exists in VP8, and it was rewri

  11 juillet 2013, par Yunqing Wang

  Changed Paths :
   Modify /vp9/encoder/vp9_encodeframe.c

  
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Add encoding option —static-thresh

  This option exists in VP8, and it was rewritten in VP9 to support
  skipping on different partition levels. After prediction is done,
  we can check if the residuals in the partition block will be all
  quantized to 0. If this is true, the skip flag is set, and only
  prediction data are needed in reconstruction. Based on DCT's energy
  conservation property, the skipping check can be estimated in
  spatial domain.

  The prediction error is calculated and compared to a threshold.
  The threshold is determined by the dequant values, and also
  adjusted by partition sizes. To be precise, the DC and AC parts
  for Y, U, and V planes are checked to decide skipping or not.

  Test showed that
  1. derf set :
  when static-thresh = 1, psnr loss is 0.666% ;
  when static-thresh = 500, psnr loss is 1.162% ;
  2. stdhd set :
  when static-thresh = 1, psnr loss is 1.249% ;
  when static-thresh = 500, psnr loss is 1.668% ;

  For different clips, encoding speedup range is between several
  percentage and 20+% when static-thresh <= 500. For example,
  clip bitrate static-thresh psnr time
  akiyo(cif) 500 0 48.923 5.635s(50f)
  akiyo 500 500 48.863 4.402s(50f)

  parkjoy(1080p) 4000 0 30.380 77.54s(30f)
  parkjoy 4000 500 30.384 69.59s(30f)

  sunflower(1080p) 4000 0 44.461 85.2s(30f)
  sunflower 4000 500 44.418 78.1s(30f)

  Higher static-thresh values give larger speedup with larger
  quality loss.

  Change-Id : I857031ceb466ff314ab580ac5ec5d18542203c53

• Revision 52256cdbca : Modify static threshold calculation Used 3 * standard_deviation in internal thr

  26 juillet 2013, par Yunqing Wang

  Changed Paths :
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Modify static threshold calculation

  Used 3 * standard_deviation in internal threshold calculation
  instead of fit curve. This actually approached the algorithm
  better.
  For comparison, similar tests were done :
  The overall psnr loss is less than before.
  1. derf set :
  when static-thresh = 1, psnr loss is 0.329% ;
  when static-thresh = 500, psnr loss is 0.970% ;
  2. stdhd set :
  when static-thresh = 1, psnr loss is 0.922% ;
  when static-thresh = 500, psnr loss is 1.307% ;

  Similar speedup is achieved. For example,
  clip bitrate static-thresh psnr time
  akiyo(cif) 500 0 48.952 5.077s(50f)
  akiyo 500 500 48.866 4.169s(50f)

  parkjoy(1080p) 4000 0 30.388 78.20s(30f)
  parkjoy 4000 500 30.367 70.85s(30f)

  sunflower(1080p) 4000 0 44.402 74.55s(30f)
  sunflower 4000 500 44.414 68.69s(30f)

  Change-Id : Ic78833642ce1911dbbd1cb6c899a2d7e2dfcc1f3

• Revision dae17734ec : New mode_info_context storage mode_info_context was stored as a grid of MODE_IN

  6 septembre 2013, par Scott LaVarnway

  Changed Paths :
   Modify /vp9/common/vp9_alloccommon.c

  
   Modify /vp9/common/vp9_alloccommon.h

  
   Modify /vp9/common/vp9_blockd.h

  
   Modify /vp9/common/vp9_debugmodes.c

  
   Modify /vp9/common/vp9_entropymode.c

  
   Modify /vp9/common/vp9_findnearmv.c

  
   Modify /vp9/common/vp9_findnearmv.h

  
   Modify /vp9/common/vp9_loopfilter.c

  
   Modify /vp9/common/vp9_mvref_common.c

  
   Modify /vp9/common/vp9_onyxc_int.h

  
   Modify /vp9/common/vp9_pred_common.c

  
   Modify /vp9/common/vp9_pred_common.h

  
   Modify /vp9/common/vp9_reconinter.c

  
   Modify /vp9/decoder/vp9_decodemv.c

  
   Modify /vp9/decoder/vp9_decodframe.c

  
   Modify /vp9/decoder/vp9_detokenize.c

  
   Modify /vp9/decoder/vp9_onyxd_if.c

  
   Modify /vp9/encoder/vp9_bitstream.c

  
   Modify /vp9/encoder/vp9_encodeframe.c

  
   Modify /vp9/encoder/vp9_encodeintra.c

  
   Modify /vp9/encoder/vp9_encodemb.c

  
   Modify /vp9/encoder/vp9_encodemv.c

  
   Modify /vp9/encoder/vp9_firstpass.c

  
   Modify /vp9/encoder/vp9_mbgraph.c

  
   Modify /vp9/encoder/vp9_mcomp.c

  
   Modify /vp9/encoder/vp9_onyx_if.c

  
   Modify /vp9/encoder/vp9_quantize.c

  
   Modify /vp9/encoder/vp9_rdopt.c

  
   Modify /vp9/encoder/vp9_segmentation.c

  
   Modify /vp9/encoder/vp9_temporal_filter.c

  
   Modify /vp9/encoder/vp9_tokenize.c

  
  
  New mode_info_context storage

  mode_info_context was stored as a grid of MODE_INFO structs.
  The grid now constists of a pointer to a MODE_INFO struct and
  a "in the image" flag. The MODE_INFO structs are now stored
  as a stream, eliminating unnecessary copies and is a little
  more cache friendly.

  For the test clips used, the decoder performance improved
  by 4.3% (1080p) and 9.7% (720p).

  Patch Set 2 : Re-encoded clips with latest. Now 1.7% (1080p)
  and 5.9% (720p).

  Change-Id : I846f29e88610fce2523ca697a9a9ef2a182e9256