Adds differential encoding of prob updates using a subexponential
code centered around the previous probability value.
Also searches for the most cost-effective update, and breaks
up the coefficient updates into smaller groups.
Small gain on Derf: 0.2%
Change-Id: Ie0071e3dc113e3d0d7ab95b6442bb07a89970030
This commit changed to enable the usage 8x8 transform for all frame
type, all resolution and all quantizer range. This has an overall
benefit .2% to .3% in term of compression, but more importantly,
the difficult clips benefits much more, up to 2% to 3% on clips
like football, harbour and so on.
We observed some weird humps on very high end on a couple of youtube
clips, but have determined the underly cause was the aggressive zbin
having an effect of lowering rate with lower quality, which have
an impact on slide show clips around 60DB.
The commit does not change the association between prediction mode
and transform size.
Change-Id: I33043bdce6207528ae00b4a4b26d8ff63cfea1f4
This is to prevent the evaluation of a mode from using values left
over from a mode evaluated prior in the loop.
Change-Id: Ife2c6ceb76d2f7365fd262515d3ae48229033c2d
With the NEWENTROPY experiment enabled encoding certain clips
produced invlid bitstreams, or files that had a high degree
of artefacts.
This was the results of pointers in MACROBLOCKD not being
setup correctly (mode_info_context and prev_mode_info_context).
Change-Id: Ice13e1efa8bd122997d2f8f3f1e761c6c16e0403
These contexts need to be saved and restored for recode, otherwise
encoder/decoder mismatch happens for some clips (eg._mobcal 720p)
Change-Id: Ic65cfa0bf56ed0472ecab962ce31394d59d344bf
Added code to save the coding context in vp8_rd_pick_inter_mode
when the coding mode is forced to ARF(0,0).
Also, modified the MV bounds computation to comply with the
change in MV border from 32 to 64 pixels.
Change-Id: I96963a6f5f4d04ce84c807ae11e0635177c3ad6c
Turning off the interpolation filter selection based on edge
proportion. This heuristics has not been working as well as
expected and I have started a more rigorous investigation into
this. We can turn this off for now since it is unnecessarily
slowing things down.
Rebase.
Change-Id: Ic5958b2b3a35ec2d8eb73b6d81617ca8fbe07e74
This commit tries to address an issue related to the oddity shown on
HD _mobcal clip, where some rather ugly blocks shown in the second
frame at low-mid bit rates if the third frame is not made a key frame
by he encoder. The fixes include: 1) made calls to sad_16x16 to be
consistent with function prototype. 2) remove the error bias to intra
and golden in mbgraph search. 3) changed the error accumulation on
inter_segment encoding to avoid potential out-of-range. 1) has no
effect on encoding results.
Encoding test show that the overall effect of the commit helps about
.2%(HD) to .3%(cif)
Change-Id: I930975a2d0c06252f01c39e0a02351529774e30b
The commit removed a limit on key frame detection, which caused a big
drop in all metric measurements for standard HD clip such as _mobcal.
This single change helps two standard HD clips by a huge amount, which
help the overall std-hd set by 2.4% (glb psnr), 0.9% (avg_psnr), 2.1%
(vpxssim).
In the result page:
http://pafr9.prod.google.com:26163/?/cns/rc-d/home/on2-prod/sunkaras/borg-test/yaowu
2012_04_02_1649_yaowu_bugfix_std-hd
2012_04_03_1452_yaowu_hump_std-hd
represent the encoding test results and std-hd set prior and after this
commit respectively.
Change-Id: Ie4313e317c737ea0e699c3a7919c1376744baa1a
This commit has made macro_block_yrd_8x8 and macro_block_yrd_8x8 to
take same parameters. It also removed a few unnecessary shifts that
has the potential to create out-of-range distortion values.
Change-Id: I4ec5afb307c3685c2a67a07c2850f0927d214455
Some code re-factored / moved to allow the main
pack operation inside the recode loop so that the
size estimate is accurate.
Deletion of some redundant code relating to one pass.
Aproximate improvement over March 27 code base:
Derf 0.0%, YT 0.5%, YThd 0.3% Std_hd 0.25%
Change-Id: Id2d071794ab44f0b52935f6fcdb5733d09a6bb86
Some adjustments to zbin for t8x8.
Changes to rules for sizing forced key frames.
Some extra stats output in tmp.stt.
Approximate gain on YT-hd set 0.5%
There are still issues in sizing key frames and gf/arf frames
when the image is largely static. These in part relate to
problems with cost estimates in the recode loop.
Change-Id: I6f0159dc8a8faeab4115a19c668d442491619a68
This is the first patch to add superblock (32x32) coding
order capabilities. It does not yet do any mode selection
at the SB level, that will follow in a further patch.
This patch encodes rows of SBs rather than
MBs, each SB contains 2x2 MBs.
Two intra prediction modes have been disabled since they
require reconstructed data for the above-right MB which
may not have been encoded yet (e.g. for the bottom right
MB in each SB).
Results on the one test clip I have tried (720p GIPS clip)
suggest that it is somewhere around 0.2dB worse than the
baseline version, so there may be bugs.
It has been tested with no experiments enabled and with
the following 3 experiments enabled:
--enable-enhanced_interp
--enable-high_precision_mv
--enable-sixteenth_subpel_uv
in each case the decode buffer matches the recon buffer
(using "cmp" to compare the dumped/decoded frames).
Note: Testing these experiments individually created
errors.
Some problems were found with other experiments but it
is unclear what state these experiments are in:
--enable-comp_intra_pred
--enable-newentropy
--enable-uvintra
This code has not been extensively tested yet, so there
is every likelihood that further bugs remain. I also
intend to do some code cleanup & refactoring in tandem
with the next patch that adds the 32x32 modes.
Change-Id: I1eba7f740a70b3510df58db53464535ef881b4d9
Found this bug while tracking down some anomalies in my experiments.
Since vp8_cost_one and vp8_cost_zero return unsigned int, the
bit shift by 8 will be incorrect if the value is negative.
I am cautiously optimistic that this fix will make the prob
updates more correct and somewhat improve results across the board.
But the update probabilities will need to be retuned I think.
Patch 2: Adding more of the same fixes using a macro.
Change-Id: I1a168f040e74e8c67e7225103b1c2af9a611da49
When ac_yquant>171, a key frame is enabled to use 8x8 transform. In
such case, MBs with DC_PRED or TM_PRED are selected to use T8x8. This
change helped the full STD-HD set by ~.1% or so, which is reasonable
considering how often key frame occurs in these encodings.
Change-Id: Id17009ef6327252177b19e6bf0d6628827febaf1
Deprecate fast quant and strict_quant code.
Small effect on quality as fast was used in first pass but the
effect is basically neutral across the derf set.
The rationale here is to reduce the number of code paths for
now to make experimentation easier. Optimized and fast code
options can be re-introduced later along with other encode
speed options.
Change-Id: Ia30c5daf3dbc52e72c83b277a1d281e3c934cdad
Various refactoring to make the subpel motion compensation
filters switchable by a frame level field.
Two types of 8-tap filters are supported in addition to the existing
bilinar and sixtap filters. One is the default 8-tap and the
other has a sharper cut-off for use with frames with substantial
edge content.
Patch 2: Added a preliminary strategy for filter selection based on
edginess detecton. Also includes some filter changes.
Change-Id: I866085bda5ae143cfdf2ec88157feaabdf7bd63a
The commit added a clamp to the 2nd motion vector used in compound
prediction to insure mv within UMV borders. The clamp is similar to
that of the first motion vector except that No SPLITMV is ever used
for the 2nd motion vector.
Change-Id: I26dd63c304bd66b2e03a083749cc98c641667116
The commit added a new command line option --test-decode to vpxenc.
The option enables encoder to decode compressed frames and test recon
buffers from the decode against those from encode for mismatch.
There are a few limitations on this option currently, one of them
being the match test is not done on a number of lagged frames at
the end of an encoding.
Change-Id: I80c29b46dcdcea9f48107a506b235743068862fe
The recoding loop save and restore frame coding context for recodes.
However in recoding of key frames, some of the coding context saved
was stale from last encoded inter frame. The save/restore sometimes
overwrites the re-inintialized coding context with saved context
from last frame, resulting in encoder/decoder mismatch
Change-Id: I354ae2f71074d142602d51d06544c05a2462caaf
this commit added a command line option to skip first n frames from
input file to facilitate debugging and testing.
Change-Id: I4ffc5f85fa7e193ea4bdee08cb236717de8beef1
This is a code snapshot of experimental work currently ongoing for a
next-generation codec.
The codebase has been cut down considerably from the libvpx baseline.
For example, we are currently only supporting VBR 2-pass rate control
and have removed most of the code relating to coding speed, threading,
error resilience, partitions and various other features. This is in
part to make the codebase easier to work on and experiment with, but
also because we want to have an open discussion about how the bitstream
will be structured and partitioned and not have that conversation
constrained by past work.
Our basic working pattern has been to initially encapsulate experiments
using configure options linked to #IF CONFIG_XXX statements in the
code. Once experiments have matured and we are reasonably happy that
they give benefit and can be merged without breaking other experiments,
we remove the conditional compile statements and merge them in.
Current changes include:
* Temporal coding experiment for segments (though still only 4 max, it
will likely be increased).
* Segment feature experiment - to allow various bits of information to
be coded at the segment level. Features tested so far include mode
and reference frame information, limiting end of block offset and
transform size, alongside Q and loop filter parameters, but this set
is very fluid.
* Support for 8x8 transform - 8x8 dct with 2nd order 2x2 haar is used
in MBs using 16x16 prediction modes within inter frames.
* Compound prediction (combination of signals from existing predictors
to create a new predictor).
* 8 tap interpolation filters and 1/8th pel motion vectors.
* Loop filter modifications.
* Various entropy modifications and changes to how entropy contexts and
updates are handled.
* Extended quantizer range matched to transform precision improvements.
There are also ongoing further experiments that we hope to merge in the
near future: For example, coding of motion and other aspects of the
prediction signal to better support larger image formats, use of larger
block sizes (e.g. 32x32 and up) and lossless non-transform based coding
options (especially for key frames). It is our hope that we will be
able to make regular updates and we will warmly welcome community
contributions.
Please be warned that, at this stage, the codebase is currently slower
than VP8 stable branch as most new code has not been optimized, and
even the 'C' has been deliberately written to be simple and obvious,
not fast.
The following graphs have the initial test results, numbers in the
tables measure the compression improvement in terms of percentage. The
build has the following optional experiments configured:
--enable-experimental --enable-enhanced_interp --enable-uvintra
--enable-high_precision_mv --enable-sixteenth_subpel_uv
CIF Size clips:
http://getwebm.org/tmp/cif/
HD size clips:
http://getwebm.org/tmp/hd/
(stable_20120309 represents encoding results of WebM master branch
build as of commit#7a15907)
They were encoded using the following encode parameters:
--good --cpu-used=0 -t 0 --lag-in-frames=25 --min-q=0 --max-q=63
--end-usage=0 --auto-alt-ref=1 -p 2 --pass=2 --kf-max-dist=9999
--kf-min-dist=0 --drop-frame=0 --static-thresh=0 --bias-pct=50
--minsection-pct=0 --maxsection-pct=800 --sharpness=0
--arnr-maxframes=7 --arnr-strength=3(for HD,6 for CIF)
--arnr-type=3
Change-Id: I5c62ed09cfff5815a2bb34e7820d6a810c23183c
The commit added a clamp to the 2nd motion vector used in compound
prediction to insure mv within UMV borders. The clamp is similar to
that of the first motion vector except that No SPLITMV is ever used
for the 2nd motion vector.
Change-Id: I26dd63c304bd66b2e03a083749cc98c641667116
The commit added a new command line option --test-decode to vpxenc.
The option enables encoder to decode compressed frames and test recon
buffers from the decode against those from encode for mismatch.
There are a few limitations on this option currently, one of them
being the match test is not done on a number of lagged frames at
the end of an encoding.
Change-Id: I80c29b46dcdcea9f48107a506b235743068862fe
The recoding loop save and restore frame coding context for recodes.
However in recoding of key frames, some of the coding context saved
was stale from last encoded inter frame. The save/restore sometimes
overwrites the re-inintialized coding context with saved context
from last frame, resulting in encoder/decoder mismatch
Change-Id: I354ae2f71074d142602d51d06544c05a2462caaf
this commit added a command line option to skip first n frames from
input file to facilitate debugging and testing.
Change-Id: I4ffc5f85fa7e193ea4bdee08cb236717de8beef1
In a previous commit, the duplicate of headerfile defaultcoefcounts.h
was identified. This commit updates the .mk file to ensure configure
and make works properly for all platforms.
Change-Id: I31a39c809a734ba438ee53db700f252e9a03eddd
The maximum psnr has a marginal impact on the overall output in high
quality encodings, the change will make sure the psnr output to be
consistent with encoder internal stats.
Change-Id: I35cf2f85008ec127a7d91c9eb69fa7811798ae32
Pulled out super block code for the snapshot as this
is not quite ready and will need an extensive re-merge.
Change-Id: I436369b511257447a7b0ea064016cb63f5011849
https://gerrit.chromium.org/gerrit/#change,17319 fixes cost estimating
to take skip_eob into account. No quality difference seen on derf set
tests, but about .4% gain on STD_HD set.
Change-Id: Ic5fe6d35ee021e664a6fcd28037b8432a0e470ca
This gives a modest gain on derf overall, although at low bitrates the
cost is still too high, so this can be improved further.
Patch 2. Re-base and fix 80 column issues
Change-Id: Ida2f9fa3fe75370669f6a27b37108dc602231c63
The commit changed to compute UV intra RD estimates for 4x4 and 8x8
separately to be used in mode decision for MB modes associated with
the appropriate transform size respectively. Now finally after many
other changes related 8x8 quantizer zbin boost and zbin_mode_boost,
this change overall helps the HD(with 8x8) by around ~.13%.
(avg .13% glb .13% ssim .17%)
The commit also has a few changes for eliminating compiler warnings.
Change-Id: Ibab35dad44820c87e6b44799c66f8d519cc37344
The commit added the correct Zbin_mode_boost initialization based on
Intra Mode before using rate distortion to pick UV intra mode.
Change-Id: I8e57878ff356a06672f6fa2431be860bf9b9a5c7
