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
We would skip the rectangular blocks for sub8x8 partitions because
we would conclude that PARTITION_NONE was better than PARTITION_SPLIT,
however, that conclusion was made before we actually really tested
PARTITION_SPLIT.
Change-Id: I8fa91e59894badc1d8cee3ba8a49e40ae4c4a489
This prevents a duplicate memcpy of a 128-byte struct every time
set_scale_factors() is called (which is a lot), thus leading to a
decrease from 3.7 MB to 1.85 MB of struct copying per 64x64 block
RD/partition loop.
Overall, this decreases encoding time of the first 50 frames of bus
@ 1500kbps (speed 0) from 1min5.9 to 1min4.9, i.e. about a 1.5%
overall speedup. We can likely get more gains by removing the copy
of the other struct (and replacing it with an indexing) as well.
Change-Id: I3dceb7e79f71e6fe911b11cc994cf89a869dde7a
This means we only do UV intra mode selection if we find any intra
mode to actually be useful at all; in addition, we only do UV intra
mode selection for the transform sizes that were selected, rather
than all sizes available in this partition.
First 50 frames of bus @ 1500kbps (speed 0) gains about 5% with this
change.
Change-Id: I7b461eb8b803247f57896c5a9505f745b55502b3
The break statement only breaks out of the nested loop, not the
top-level loop, so it doesn't always work as intended. Changing it
to a return statement does what's intended.
Change-Id: I585419823b39a04ec8826b1c8a216099b1728ba7
This could happen during golden overlay frame coding from a previous
alt-ref frame if the special overlay code was triggered.
Change-Id: I3056d0c547cd26903b260ef93c94026e96bd9868
These arrays have constant values (no any updates). Removing two
corresponding memcpy calls. Making a little cleanup in vp9_entropymode.h
as well: removing redundant 'extern' keyword and moving all function
declarations at the end.
Change-Id: Ia16b38b46aec2e2500f5df29c40a297ae241dede
vp9_init_quantizer() is called in vp9_create_compressor(), and
should not be called in vp9_set_speed_features().
Change-Id: Ic2f1f4b0531b9d46bb841d7e1d8da9812207dad6
Encoding of first 50 frames of bus (speed 0) @ 1500kbps goes from
1min6.2 to 1min5.9, i.e. 0.5% faster overall.
Change-Id: I59d8a3b2f0a75010fa041d5e2646c8caac5bd683
