Most of the current decoders use tile-based multithreading. Also
most of the current decoders need frame_parallel_decoding_mode
turned on to enable multithreaded decoding. tile-columns is
limited by resolution, so setting to max (6) is fine.
BUG=https://code.google.com/p/webm/issues/detail?id=963
Change-Id: I6e7ac3485d96bf0c69e06706cbb326dd38be0020
This commit replaces the SAD with variance as metric for the
integral projection vector match. It improves the search accuracy
in the presence of slight light change. The average speed -6
compression performance for rtc set is improved by 1.7%. No speed
changes are observed for the test clips.
Change-Id: I71c1d27e42de2aa429fb3564e6549bba1c7d6d4d
This commit fixes an issue in source frame border extension. It
causes certain frame resolution such as 640x480 to have a portion
of the right/bottom extension filled by zeros, which misleads
motion search and degrades transform coding performance when large
block size is used.
This fix improves the speed 2 compression performance of a few
yt sequence, typically ranging from 1% - 2%, up to 5% at median
to low bit-rate.
Change-Id: Id6b09a5695d9e7651c6dfbc2c6a72288b08af7fb
This commit applies one-step refinement search to the resulting
motion vector of the integral projectiion based motion estimation,
per 64x64 block. It improves the coding performance of speed -6.
pedestrian 1080p 500 kbps
51735 b/f, 36.794 dB, 16044 ms ->
51382 b/f, 36.793 dB, 16282 ms
cloud 1080p 500 kbps
24081 b/f, 37.988 dB, 14016 ms ->
23597 b/f, 38.076 dB, 12774 ms
vidyo1 720p 1000 kbps
16552 b/f, 40.514 dB, 8279 ms ->
16553 b/f, 40.543 dB, 8510 ms
The rtc set compression performance is improved by 0.5%.
Change-Id: I3d09bea2caf58b2a4f3b38aa26fffafcbe9a2c17
The intrinsic statement _mm_subs_epi16() should take immediate.
Feeding variable as its input argument will cause compile failure
in older version gcc.
Change-Id: I6a71efcc8d3b16b84715e0a9bcfa818494eea3f4
This commit modifies the hierarchical vector match patter. It
avoids repeated SAD computation at same points. The function
vp9_vector_sad_sse2 is called 12 times per 64x64 block, instead
of 15 times as before. The effective coverage remains the same.
Change-Id: I91ad9d27d40db8963c907d02af84e10702136994
In ssse3 functions, DEFINE_ARGS macro hard codes qcoeff and dqcoeff
to r3 and r4. If skip is 1, qcoeff and dqcoeff need to be loaded
from the stack, which doesn't work because of the above definitions.
Currently, skip=1 case is not used in the encoder. This patch fixed
the issue, so it can be turned on later.
Change-Id: I998d696b1a7a85dca2b3bcee790b21c21e039147
When GF group adaptive maxQ is enabled this patch accounts
somewhat for accumulated error in the rate control.
This improves accuracy quite a bit on many clips especially
when there is overshoot.
Examples when the overshoot and undershoot command line
parameters are set to 100:
Hall @ 1200 overshoot is reduced from 67-24%.
Akiyo @ 400 undershoot is reduced from 28%-15%.
Setting a lower value for undershoot or overshoot still
reduces the error further.
Impact on metrics is mixed with some gains in average psnr
but generally a little lower (e.g. 0.5%) on overall and ssim.
The GF group adaptation is still off by default in this patch.
Compared to with the head, enabling this mode now gives
big average psnr gains on the YT sets (e.g. YT_HD >11.2%),
a drop in overall PSNR (YT-HD 3.9%) and a smaller drop or
neutral for SSIM.
Change-Id: If4b32cd0740d3fb941317b374f9c2951954eee90
Target higher delta-qp for big blocks with zero motion,
and for segment#1: avoid 64x64 partition size and force 8x8 tx size.
Metrics on RTC set mostly positive: SSIM up by ~4%, PSRN by ~1.5%.
Doesn't seem to be any change in speed.
Change-Id: I1f68fa3c4f62dab3b90cc58041f05ebb048ae5ac
Modified the thresholds of deciding whether or not to skip
the transforms in model_rd_for_sb_y(). Used zbin[] instead
of dequant[] to be more precise. Also, modified the checking
coditions.
Rtc set borg test results (at speed 6) showed:
average PSNR gain: 0.138%, overall PSNR gain: 0.158%,
and SSIM gain: 0.177%.
The data rate test was modified slightly as suggested by
Marco.
Change-Id: Ieaf633ab77f4838cb3c45cf69065b29d55f8ae6c
