For real-time mode at speed 8: turn off MINIMAL_LF at speed 8,
for non-screen content mode.
Visually better, avgPSNR/SSIM on rtc set go up by ~4-5%.
Speed decrease of about ~3%.
Change-Id: I8eb69330f02e0ceece1507d43cfc8a049a1d8291
Using a tighter resize constraint on undershoot seems to help
results (especially SSIM) as significant undershoot on a frame
seems to have more of a damaging impact than overshoot.
This patch has been tuned so that in local testing using the
derf set it is encode speed neutral for speed setting 2.
Average quality result for speed 2 (psnr,ssim) were as follows:-
lowres 0.039, 0.453
midres 0.249, 0.853
hdres 0.159, 0.659
NetFlix -0.241, 0.360
Change-Id: Ie8d3a0d7d6f7ea89d9965d1821be17f8bda85062
This patch is to address concerns that changes to allow
recodes on the first frame in each ARF group do not give a
good enough speed quality trade off for speed 2. Though the
average impact on encode speed is 1-2%, for some hard clips
it is > 5% rise. For speed 1 this is less an issue and for Speed 0
the previous patch actually improves speed.
Change-Id: Ie1bcefdbfdf846d3f4428590173f621465dffe3a
Previously Tx domain rd was used in all cases above speed 0.
Coefficient optimization was only enabled for best and speed 0.
This patch selectively sets these features at other speed settings
based on block complexity.
For the Netflix and HD sets in particular the quality gains are
large compared to the speed hit. At speed 1 the average psnr
gain in the NF set is > 2.5% with one clip coming in at 18%
and some points almost 30%. Average gains for the lower
resolution test sets are around 1%.
The gains are biggest at low Q so some further optimization
may be possible.
Change-Id: I340376c7b2a78e5389a34b7ebdc41072808d0576
Disabled the split mode while encoding 4k video to speed
up the encoder.
Borg test result on 4k set:
Overall PSNR: +0.029%; SSIM: +0.009%.
Average encoder speedup at speed 2 is 2.5%.
Change-Id: I1519c658f07c3ac838affbe5aff0ed9b94f3f8f4
Adjusted speed 2 features to speed up 4k video encoding.
BDBR results from borg test:
PSNR: +0.313%; SSIM: +0.268%.
Average speedup: 8.5%
Change-Id: I1e2695a01fb3f3817c1df4480e184c2aed8f2eba
Bias towards base_mv and skip 1/4 pixel motion search when using base mv.
2~3% speed up for 2 spatial layers, 3~5% speed up for 3 spatial layers.
PSNR loss:
(2 layers) 0.07dB for gips_stationary, 0.04dB for gips_motion;
(3 layers) 0.07dB for gips_stationary, 0.06dB for gips_motion.
Change-Id: I773acbda080c301cabe8cd259f842bcc5b8bc999
Add option, for newmv-last, to limit the rd-threshold update for early exit,
under a source varianace condition.
This can improve visual quality in low texture moving areas,
like forehead/faces.
Also add bias against golden to improve the speed/fps,
will little/negligible loss in quality.
Only affects CBR mode, non-svc, non-screen-content.
Change-Id: I3a5229eee860c71499a6fd464c450b167b07534d
Changes the default recode rule for Speed 0 and best quality
from ALLOW_RECODE to ALLOW_RECODE_KFARFGF.
Tested on the NF, hdres, midres and lowres test sets, this setting
when combined with patch I40cb559... now performs "as well" in
metrics terms (in fact it came out a tiny amount better overall)
but encode time is 9.6% faster (measured as the average
from 27 mid rate local encodes on clips in the derf/lowres set.
Change-Id: I8c781c0cdfa3a9929cd9406d15582fce47d6ae3b
This commit allows the inter prediction residual to use uniform
quantization followed by trellis coefficient optimization in
speed 0. It improves the coding performance by
lowres 0.79%
midres 1.07%
hdres 1.44%
Change-Id: I46ef8cfe042a4ccc7a0055515012cd6cbf5c9619
Use pixel domain distortion metric in speed 0. This improves the
compression performance by 0.3% for both low and high resolution
test sets.
Change-Id: I5b5b7115960de73f0b5e5d0c69db305e490e6f1d
1. Skip golden non-zeromv and newmv-last for bsize >= 16x16 if the
temporal variance obtained from choose_partitioning is very low.
2. Skip horz and vert INTRA mode for speed 8.
This change works best on the clips with little noise and with some
motion (e.g. gips_motion which has > 5% speed up). PSNR drop is 1.78%
on rtc test set, no obvious visual quality regression found.
Change-Id: Ib43b5b20e67809d03c5a6890818ddff59e1fc94a
Skip intra-mode and some inter-modes (newmv, nearmv, nearestmv) for
golden frame if the variance got from choose_partitioning is very low.
Only for 1 pass real-time CBR mode and bsize >= 32x32, it has ~2.5%
speed up with less than 0.1% PSNR drop for rtc test set. Don't see
visual regression.
Change-Id: I70efbc95a1007231ae36f02c5b2fbf6cd35077ad
Change only affects 1 pass, vbr, speed = 5 (real-time mode).
Some improvement for high motion content.
AvgPSNR/SSIM metrics for ytlive set all up, on average ~2%,
some clips (high motion ones) up 4/5%.
Encoder speed down: on mynintendo_x1.1280_720.y4m: 47fps -> 44fps.
Change-Id: I9e3eaa6392dcb6b5b44ee6f43004f97ba859bc11
+5.857% BD-RATE on SCREEN_CONTENT
Leaving this off for non-screen content because:
+25.300% on TWITCH120
+37.833% BD-RATE on RTC
Change-Id: Ie0a312182d6cc859fb04298e4cd81d02b39e23fe
Add frame-level condition for reference masking: under external or
internal dynamic resize, allow for reference masking if none of
the references have been scaled.
Peviously, reference masking was turned off for the stream if dynamic
resize feature was enabled or an external resize event occurred.
reference_masking gives speed up with little/no loss in compression.
For speed 7 on rtc set: encoding time decreases by about 5-7%,
avgPSNR/SSIM goes down ~0.2%.
Change-Id: Ie4444577451ef954414d8fb4b2c99d65cadf1746
An issue exists with reference_masking in non-rd pickmode for spatial
scaling. It was kept off for internal dynamic resizing and svc, this
change is to keep it off also for external dynamic resizing.
Update to external resize test, and update TODO to re-enable this
at frame level when references have same scale as source.
Change-Id: If880a643572127def703ee5b2d16fd41bdbf256c
In inter mode search skip all modes except NEARESTMV and DC_PRED.
10% less encode latency for large frames using the chromium remoting_perftests.
+0.313% BDRATE on the screencast set at speed -6.
Change-Id: Ib97a39dd8bcdeab545509e0e02d78ce7033f8c63
H/V intra mode was only enabled for bsize < 16x16,
enable it also for bsize=16x16.
Metrics are neutral with this change:
Overall very small gain (0.1%), small visual gain on some RTC clips.
Change-Id: Ib2d7a44382433bfc11cf324aa3cc5c382ea9e088
For denoising, and for noise level above threshold, re-evaluate
ZEROMV for mode selection after denoising.
Current change only does this check if selected best mode (before denoising)
was intra.
Change-Id: I4b1435b68d26c78f7597b995ee7bff0ddd5f9511
Small changes to the best quality default speed trade off.
Some speedup settings are worth while even for best quality as they
have only a very small impact on quality but a significant impact on
encode time.
These changes give as much as a further 50-60% increase in encode
speed for my test animations clip with minimal impact on quality.
For this sequence these changes improve the best quality encode speed
to about the same level as good quality speed 0 in Q3 2015 whilst
retaining the large quality gain of over 1 db
For many natural videos though the quality difference from good 0
to best is much smaller.
Change-Id: I28b3840009d77e129817a78a7c41e29cb03e1132
This change alters the nature and use of exhaustive motion search.
Firstly any exhaustive search is preceded by a normal step search.
The exhaustive search is only carried out if the distortion resulting
from the step search is above a threshold value.
Secondly the simple +/- 64 exhaustive search is replaced by a
multi stage mesh based search where each stage has a range
and step/interval size. Subsequent stages use the best position from
the previous stage as the center of the search but use a reduced range
and interval size.
For example:
stage 1: Range +/- 64 interval 4
stage 2: Range +/- 32 interval 2
stage 3: Range +/- 15 interval 1
This process, especially when it follows on from a normal step
search, has shown itself to be almost as effective as a full range
exhaustive search with step 1 but greatly lowers the computational
complexity such that it can be used in some cases for speeds 0-2.
This patch also removes a double exhaustive search for sub 8x8 blocks
which also contained a bug (the two searches used different distortion
metrics).
For best quality in my test animation sequence this patch has almost
no impact on quality but improves encode speed by more than 5X.
Restricted use in good quality speeds 0-2 yields significant quality gains
on the animation test of 0.2 - 0.5 db with only a small impact on encode
speed. On most clips though the quality gain and speed impact are small.
Change-Id: Id22967a840e996e1db273f6ac4ff03f4f52d49aa
Changes to the breakout behavior for partition selection.
The biggest impact is on speed 0 where encode speed in
some cases more than doubles with typically less than 1%
impact on quality.
Speed 0 encode speed impact examples
Animation test clip: +128%
Park Joy: +59%
Old town Cross: + 109%
Change-Id: I222720657e56cede1b2a5539096f788ffb2df3a1
For speed 7, real-time mode: Base layer frames are further apart
(for #temporal layers = 3, this is every 4 frames) so worth keeping
same motion search parameters (as in speed 6) on the base layer frames.
Change-Id: Idebf49dda6ef4f3d9a55aee55129a68253f692fb
This got erroneously changed during the refactor. This fixes
SvcTest.TwoPassEncode2TemporalLayersWithMultipleFrameContextsAndTiles.
Change-Id: Ifa5ab0e098396c5e2d10478db87df256eadfa4c7
Fix bug in setting this flag for animated content.
The bug did cause quality to increase because far
more frames are not boosted than boosted.
However, the speed trade off to gain is a lot less
favorable and the behavior was not as intended.
Change-Id: I89fb70419c88b26f40b3534de0481730a1b3fcfa
Changes to allow more use of rectangular partitions at
speeds 1 and 2 for content classed by the first pass as
animation and for blocks near the active image edge.
This has quite a big impact in quality for the animated
test sequence but also hurts encode speed for speed 2.
For other content types the impact on both speed and
quality is small.
Added some plumbing for detection of internal vertical
image edges.
Change-Id: I3fc48de2349f8cb87946caaf0b06dbb0ea261a9a
Change speed features / behavior for split mode when there
is an internal active edge (e.g. formatting bars).
Remove some threshold constraints in rd code near the active
edge of the image.
Add some plumbing for left and right active edge detection.
Patch set 5. Limit rd pass through for sub 8x8 to internal active edges.
This takes away any speed penalty for most clips but keeps the enhanced
edge coding for the more critical case of internal image edges
Change-Id: If644e4762874de4fe9cbb0a66211953fa74c13a5
For content that is identified as likely to contain some
animation or graphics content, increase the availability
of split modes for good quality speeds 1-3.
On a problem test animation clip this improves metrics
results by about 0.25 db and makes a noticeable difference
visually. It also causes a small drop in file size (~0.5%) but
a rise in encode time of about 5-6% at speed 2.
For more normal content it should have no effect.
Change-Id: Ic4cd9a8de065af9f9402f4477a17442aebf0e439
Adds code to detect dead zone bars at the top and bottom
of reformatted letterbox video (note that the code only
looks at the top of the image and assumes any dead zone
is symmetrical). Use of this to adapt rate control etc.
will follow in a subsequent patch.
Also counts other blocks (excluding the dead zone) that
have no intra signal. The presence of a significant
number of such blocks can be used as a identify that the frame
may be artificial (e.g. animation, screen capture, graphics).
This patch contains plumbing only and does not use
the signal.
Change-Id: I59bc93529cd4065416cef773e405fda3ae006a20
Use the same settting as in speed >=6.
This will use same logic for tx_size selecton as in speed >=6,
which limits the transform size and reduces ringing artifact.
Also metrics go up on average with this change: ~2% for PSNR, ~10% for SSIM.
Change-Id: Ia2d50db236ae1cc72f742bfa6c9ec5ea50ff0e0a
For non-rd mode (speed >=5): use mask based on prediction block size, and
(for non-screen content mode) allow for checking horiz and vert intra modes
for blocks sizes < 16x16.
Avg psnr/ssim metrics go up by about ~0.2%.
Only allowing H/V intra on block sizes below 16x16 for now, to keep
encoding time increase very small, and also when allowing H/V on 16x16 blocks,
metrics went down on a few clips which need to be further examined.
Change-Id: I8ae0bc8cb2a964f9709612c76c5661acaab1381e
Impose a limit on the rd auto partition search based on
the image format. Smaller formats require that the search
includes includes a smaller minimum block size.
This change is intended to mitigate the visual impact of
ringing in some problem clips, for smaller image formats.
Change-Id: Ie039e5f599ee079bbef5d272f3e40e2e27d8f97b
Remove one of the auto partition size cases.
This case can behaves badly in some types of animated content
and was only used for the rd encode path. A subsequent patch
will add additional checks to help further improve visual quality.
Change-Id: I0ebd8da3d45ab8501afa45d7959ced8c2d60ee4e
