1. block types
There are only three types of blocks for 8x8 transformed MBs, i.e. Y
block with DC does not exist for 8x8 transformed MBs as all MB using
8x8 transform have 2nd order haar transform. This commit introduced
a new macro BLOCK_TYPES_8X8 to reflect such fact.
2. context counters
This commit also fixed the mixed of context_counters between 4x4 and
8x8 transformed MBs. The mixed use of the counters leads me to think
the existing the context probabilities were not properly generated
from 8x8 transformed MBs.
3. redundant collecting in recoding
The commit also corrected the code that accumulates entropy stats by
making sure stats only collected for final packing, not during the
recode loop
Change-Id: I029f09f8f60bd0c3240cc392ff5c6d05435e322c
This commit adjusted slightly the 4x4 coefficents band definition to
better classify coefficients with similar distributions and usages.
It helps derf set about .1%, it is alos slightly positive for std-hd
set, where 4x4 blocks are used less frequently.
The commit also removed a const array not in use.
Change-Id: I78d16905d4036641ec905b0c32c190c1def5b249
This commit merge the QI mode experiment. As the experiment affects
the encoding of intra coding modes on key frame only, the overall
effect of the experiment on encoding tests is insignificant.
Change-Id: I9e4e3933adface88867ad429cee3986e529c511d
The commit merges the UVINTRA experiment and removed the related
macros. The overall effect of the experiment is a small gain (.1%
on derf)
Change-Id: Ia34b3312fb9b5b34c9ba111bf0fa78c6f78ac80b
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
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
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
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 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
This is the first patch for refactoring of the code related to
high-precision mv, so that 1/4 and 1/8 pel motion vectors can
co-exist in the same bit-stream by use of a frame level flag.
The current patch works fine for only use of 1/4th and
only use of 1/8th pel mv, but there are some issues with the
mode switching in between. Subsequent patches on this change Id
will fix the remaining issues.
Patch 2: Adds fixes to make sure that multiple mv precisions can
co-exist in the bit-stream. Frame level switching has been tested
to work correctly.
Patch 3: Fixes lines exceeding 80 char
Patch 4:
http://www.corp.google.com/~debargha/vp8_results/enhinterp.html
Results on derf after ssse3 bugfix, compared to everything
enabled but the 8-tap, 1/8-subpel and 1/16-subpel uv. Overall the
gains are about 3% now. Hopefully there are no more bugs lingering.
Apparently the sse3 bug affected the quartel subpel results more than
the eighth pel ones (which is understandabale because one bad predictor
due to the bug, matters less if there are a lot more subpel options
available as in the 1/8 subpel case).
The results in the 4th column correspond to the current settings.
The first two columns correspond to two settings of adaptive switching
of the 1/4 or 1/8 subpel mode based on initial Q estimate. These
do not work as good as just using 1/8 all the time yet.
Change-Id: I3ef392ad338329f4d68a85257a49f2b14f3af472
For now the interface elements have been left in place
to make sure existing parameter files work but parameters
relating to drop frame wont do anything.
Change-Id: I579ee614726387381c546845dac4bc03c74c6a07
The Lagrangian interpolation filter is maximally flat in the
passband. There is non-trivial improvement with the hd set, while
for derf the results are virtually unchanged.
See:
http://www.corp.google.com/~debargha/vp8_results/enhinterpn.html (derf)
http://www.corp.google.com/~debargha/vp8_results/enhinterpn_hd.html (HD)
Patch 2: Updated the results for derf in the html above to use the
new baseline. There is still about 4% improvement. Will update the
hd baseline later (since it takes 9 hours to run on my machine)
Patch 3: By mistake the default filter was left at 60 - should be 0
to use the new interpolation filter.
Change-Id: If5f64444976562415d68a2aeabb94fdfa0d47890
* Removes EDGE_PIXEL_FILTER for external sanpshot
* changes the default 8-tap filter based on high precision results
in http://www.corp.google.com/~debargha/vp8_results/enhinterpn.html
* changes the default prob tables for high-precision mv encoding to
favor zeros in the last bit (i.e. quarter pel). This is only important
for short clips.
Change-Id: I02bb0de8679d9eec06cdbcc8160dbf073cd847a4
This is the initial patch for supporting 1/8th pel
motion. Currently if we configure with enable-high-precision-mv,
all motion vectors would default to 1/8 pel. Encode and
decode syncs fine with the current code. In the next phase
the code will be refactored so that we can choose the 1/8
pel mode adaptively at a frame/segment/mb level.
Derf results:
http://www.corp.google.com/~debargha/vp8_results/enhinterp_hpmv.html
(about 0.83% better than 8-tap interpoaltion)
Patch 3: Rebased. Also adding 1/16th pel interpolation for U and V
Patch 4: HD results.
http://www.corp.google.com/~debargha/vp8_results/enhinterp_hd_hpmv.html
Seems impressive (unless I am doing something wrong).
Patch 5: Added mmx/sse for bilateral filtering, as well as enforced
use of c-versions of subpel filters with 8-taps and 1/16th pel;
Also redesigned the 8-tap filters to reduce the cut-off in order to
introduce a denoising effect. There is a new configure option
sixteenth-subpel-uv which will use 1/16 th pel interpolation for
uv, if the motion vectors have 1/8 pel accuracy.
With the fixes the results are promising on the derf set. The enhanced
interpolation option with 8-taps alone gives 3% improvement over thei
derf set:
http://www.corp.google.com/~debargha/vp8_results/enhinterpn.html
Results on high precision mv and on the hd set are to follow.
Patch 6: Adding a missing condition for CONFIG_SIXTEENTH_SUBPEL_UV in
vp8/common/x86/x86_systemdependent.c
Patch 7: Cleaning up various debug messages.
Patch 8: Merge conflict
Change-Id: I5b1d844457aefd7414a9e4e0e06c6ed38fd8cc04
The commit rationized and simplified the entropy context conversion
betwen MB using 8x8 transform and MB using 4x4 transform. The old version
had a number of weirdness in how 4x4 transform MB's context is used for
8x8 blocks other than the first 8x8 within a MB.
Test showed the change has a gain ~.1% for avg psnr, glb psnr and ssim on
the limited HD set.
Change-Id: I774536c416baa6845aa741f956d8a69fa40e5d47
Removal of the pickinter.c and .h files and calls to this
code.
Removal of some code relating to real time and one pass
settings though there is more to be done in this regard.
However, vp8_set_speed_features() now
only supports modes 0 and 1 and speeds up to 3
so rd should always be set.
Change-Id: I62c0c1b6154ab499785baef310536080e87bc4d8
the changes are still temporary, the final transforms, especially
inverse ones should take in account both accuracy, complexity, and
sign-bias, which should be decided at a later time.
Change-Id: I116b0c70b25f5ee324ae5713d4564f5d0aa27151
During the work of extend_qrange, we have rolled a factor of 2 from
quantization/dequatnization into 2nd order walsh-hadamard transform.
This commit does the same for the 2nd order haar transform. so they
can share the same quantizaiton process as the 2nd order WHT.
Change-Id: I734af4a20ea8149a01b5b1971a065092977dfe33
Previously, the scaling related to extended quantize range happens in
dequantization stage, which implies the coefficients form forward
transform are in different scale(4x) from dequantization coefficients
This worked fine when there was not distortion computation done based
on 8x8 transform, but it completely wracked the distortion estimation
based on transform coefficients and dequantized transform coefficients
introduced in commit f64725a00 for macroblocks using 8x8 transform.
This commit fixed the issue by moving the scaling into the stage of
inverse 8x8 transform.
TODO: Test&Verify the transform/quantization pipeline accuracy.
Change-Id: Iff77b36a965c2a6b247e59b9c59df93eba5d60e2
This commit moved segment based loop filter level selection into
the experiment of CONFIG_FEATUREUPDATES. As previous commit noted,
the segment based loop filter selection helps the compression by
~0.1% on cif set, the ongoing experiment CONFIG_FEATUREUPDATES
made encoding updates of the segment based LPF level more efficient,
hence, another .04% gain on cif set. The commit also fixed an issue
previously where encoder/decoder may use different loop filter level
for one of the segments.
Change-Id: Ia978b14aae95bb107d561ba53a7a2bb6ff01faf3
Added a bit to signify that the feature changed since
the last time we sent it, or not so that we don't need
to send all the databits for every feature change.
added config
Change-Id: I8d3064ce90d4500bf0d5c6b87c664e46138dfcac
For the experimental branch we are trying to slim the codebase
down removing features such as threading for now which complicate
the process of development and testing.
Change-Id: I657c0246aef4d1fa8c8ffc6a1adfeee45bce8e24
In summary, this commit encompasses a series of changes in attempt to
improve the 8x8 transform based coding to help overall compression
quality, please refer to the detailed commit history below for what
are the rationale underly the series of changes:
a. A frame level flag to indicate if 8x8 transform is used at all.
b. 8x8 transform is not used for key frames and small image size.
c. On inter coded frame, macroblocks using modes B_PRED, SPLIT_MV
and I8X8_PRED are forced to using 4x4 transform based coding, the
rest uses 8x8 transform based coding.
d. Encoder and decoder has the same assumption on the relationship
between prediction modes and transform size, therefore no signaling
is encoded in bitstream.
e. Mode decision process now calculate the rate and distortion scores
using their respective transforms.
Overall test results:
1. HD set
http://www.corp.google.com/~yaowu/no_crawl/t8x8/HD_t8x8_20120206.html
(avg psnr: 3.09% glb psnr: 3.22%, ssim: 3.90%)
2. Cif set:
http://www.corp.google.com/~yaowu/no_crawl/t8x8/cif_t8x8_20120206.html
(avg psnr: -0.03%, glb psnr: -0.02%, ssim: -0.04%)
It should be noted here, as 8x8 transform coding itself is disabled
for cif size clips, the 0.03% loss is purely from the 1 bit/frame
flag overhead on if 8x8 transform is used or not for the frame.
---patch history for future reference---
Patch 1:
this commit tries to select transform size based on macroblock
prediction mode. If the size of a prediction mode is 16x16, then
the macroblock is forced to use 8x8 transform. If the prediction
mode is B_PRED, SPLITMV or I8X8_PRED, then the macroblock is forced
to use 4x4 transform. Tests on the following HD clips showed mixed
results: (all hd clips only used first 100 frames in the test)
http://www.corp.google.com/~yaowu/no_crawl/t8x8/hdmodebased8x8.htmlhttp://www.corp.google.com/~yaowu/no_crawl/t8x8/hdmodebased8x8_log.html
while the results are mixed and overall negative, it is interesting to
see 8x8 helped a few of the clips.
Patch 2:
this patch tries to hard-wire selection of transform size based on
prediction modes without using segmentation to signal the transform size.
encoder and decoder both takes the same assumption that all macroblocks
use 8x8 transform except when prediciton mode is B_PRED, I8X8_PRED or
SPLITMV. Test results are as follows:
http://www.corp.google.com/~yaowu/no_crawl/t8x8/cifmodebase8x8_0125.htmlhttp://www.corp.google.com/~yaowu/no_crawl/t8x8/hdmodebased8x8_0125log.html
Interestingly, by removing the overhead or coding the segmentation, the
results on this limited HD set have turn positive on average.
Patch 3:
this patch disabled the usage of 8x8 transform on key frames, and kept the
logic from patch 2 for inter frames only. test results on HD set turned
decidedly positive with 8x8 transform enabled on inter frame with 16x16
prediction modes: (avg psnr: .81% glb psnr: .82 ssim: .55%)
http://www.corp.google.com/~yaowu/no_crawl/t8x8/hdintermode8x8_0125.html
results on cif set still negative overall
Patch 4:
continued from last patch, but now in mode decision process, the rate and
distortion estimates are computed based on 8x8 transform results for MBs
with modes associated with 8x8 transform. This patch also fixed a problem
related to segment based eob coding when 8x8 transform is used. The patch
significantly improved the results on HD clips:
http://www.corp.google.com/~yaowu/no_crawl/t8x8/hd8x8RDintermode.html
(avg psnr: 2.70% glb psnr: 2.76% ssim: 3.34%)
results on cif also improved, though they are still negative compared to
baseline that uses 4x4 transform only:
http://www.corp.google.com/~yaowu/no_crawl/t8x8/cif8x8RDintermode.html
(avg psnr: -.78% glb psnr: -.86% ssim: -.19%)
Patch 5:
This patch does 3 things:
a. a bunch of decoder bug fixes, encodings and decodings were verified
to have matched recon buffer on a number of encodes on cif size mobile and
hd version of _pedestrian.
b. the patch further improved the rate distortion calculation of MBS that
use 8x8 transform. This provided some further gain on compression.
c. the patch also got the experimental work SEG_LVL_EOB to work with 8x8
transformed macroblock, test results indicates it improves the cif set
but hurt the HD set slightly.
Tests results on HD clips:
http://www.corp.google.com/~yaowu/no_crawl/t8x8/HD_t8x8_20120201.html
(avg psnr: 3.19% glb psnr: 3.30% ssim: 3.93%)
Test results on cif clips:
http://www.corp.google.com/~yaowu/no_crawl/t8x8/cif_t8x8_20120201.html
(avg psnr: -.47% glb psnr: -.51% ssim: +.28%)
Patch 6:
Added a frame level flag to indicate if 8x8 transform is allowed at all.
temporarily the decision is based on frame size, can be optimized later
one. This get the cif results to basically unchanged, with one bit per
frame overhead on both cif and hd clips.
Patch 8:
Rebase and Merge to head by PGW.
Fixed some suspect 4s that look like hey should be 64s in regard
to segmented EOB. Perhaps #defines would be bette.
Bulit and tested without T8x8 enabled and produces unchanged
output.
Patch 9:
Corrected misalligned code/decode of "txfm_mode" bit.
Limited testing for correct encode and decode with
T8x8 configured on derf clips.
Change-Id: I156e1405d25f81579d579dff8ab9af53944ec49c
Merged in most of the current common prediction changes
that were under the #if CONFIG_COMPRED option.
Change-Id: If4e6f61dbe7b86dd449f6effbe93b5eb7e893885
Further changes to make experiments with the context
used for coding the dual pred flag easier.
Current best performing method tested on derf is a two
element context based on reference frame. I also tried
various combinations of mode and reference frame as
shown in commented out case using up to 6 contexts.
Derf +0.26 overall psnr +0.15% ssim vs original method.
Change-Id: I64c21ddec0abbb27feaaeaa1da2e9f164ebaca03
Further use of common prediction functions and experiments
with alternate contexts based on mode and reference frame.
For the Derf set using reference frame as basis of context
gives +0.18% Overall Psnr and +0.08 SSIM
Change-Id: Ie7eb76f329f74c9c698614f01ece31de0b6bfc9e
This commit merges the NEWNEAR experiment such that it
is effectively always on.
The fact that there were changes in the threading code again
highlights the need to strip out such features during the
bitstream development phase as trying to maintain this code
(especially as it is not being tested) slows the development cycle.
Change-Id: I8b34950a1333231ced9928aa11cd6d6459984b65
Initial modifications to make limited use of common prediction
functions.
The only functional change thus far is that updates to the probabilities are
no longer "damped". This was a testing convenience but in fact seems to
help by a little over 0.1% over the derf set.
Change-Id: I8b82907d9d6b6a4a075728b60b31ce93392a5f2e
Trial of a modified prediction function that ranks each possible
reference frame based on a combination of local usage and
frame level probability. The code is a bit cleaner and simpler.
In direct comparison with old unpredicted method with segment level
coding turned off for mode,ref & EOB the prediction gives a gain on derf
of around 0.4%. There is some further gain from bug fixes over earlier code.
With segment coding on the prediction method is slightly -ve on some very
easy clips (at low rates) due to slightly higher overheads, but better on harder
clips. Overall neutral on derf in direct comparison on latest code base, but
compared to earlier code without bug fixes about +0.7% overall psnr
+0.3% SSIM.
Change-Id: I5b8474658b208134d352d24f6517f25795490789
Extended prediction and coding of reference frame where
a subset of options are flagged as available at the segment level.
Updated copyright notices.
Switch to SAD in mbgraph code as SATD problematic for the
foreground and background separation as it can ignore large DC shifts.
Change-Id: I661dbbb2f94f3ec0f96bb928c1655e5e415a7de1
This function adds the common prediction modules, some data structures
and a config option but does not use them.
It also corrects a bug in clearing down the MODE_INFO border and introduces
a new element that indicates if an entry corresponds to an "in image" macro block
or is part of the border.
Change-Id: Ib69eec0876173ebe9d1de9df9537d0b2447702e0
Picks a per segment loopfilter. Adapts the algorithm to search for
a loopfilter value for each separate segment. Further todo fix the
bias
Improvements .06 % ov psnr, .11% ssim
http://www.corp.google.com/~jimbankoski/no_crawl/segmentedpicklpf.html
Change-Id: Ic6a571c16fcd6ec0139f4de1f8061f87c6515a10
using an 8-tap filter.
The results with 3 different 8-tap filters on the derf set are in:
http://www.corp.google.com/~debargha/vp8_results/enhinterp.html
The one that gives the most gain achieves an overall gain of about
0.6%. The results for a set of 12 hd (720p) videos are in:
http://www.corp.google.com/~debargha/vp8_results/enhinterp_hd.html
with max gain of 0.55% with the same filter. The best filter apparently
achieves the best trade-off between pass band ripple and stop band
attenuation.
Change-Id: I919e28ae245c0493147fa0864f8c9d048a9dd530
This introduces base functions for introducing implicit segmentation.
The code that actually stores the results to the segment map isn't
here yet. This just prints out the segmentation map results
if you call it.
Uses connected component labeling technique on mbmi info so that only
if 2 mbs are horizontally or vertically touching do they get the same
segment.
vp8next - plumbing for rotation
code to produce taps for rotation ( tapify. py ), code
for predicting using rotation ( predict_rotated.c ) , code
for finding the best rotation find_rotation.c.
didn't checkin code that uses this in the codec. still work
in progress.
Fixed copyright notice
Change-Id: I450c13cfa41ab2fcb699f3897760370b4935fdf8
This commit added a set of loop filter functions for macroblocks
using 8x8 transform. First we turned off the regular loop filtering
on 4x4 block boundaries that do not exist in macroblocks using 8x8
transform. Second, we change to use the same loop filter(mask and
7 tap filter) that used for macroblock edge filtering.
Change-Id: I3a00460b7674ced116917d86812ffc32578c1d3a
The commit adds a new set of loop filter for macroblock edge filtering.
The new loop filter has a mask to detect so-called "flat" regions. The
detection checks 5 pixels of each side of an edge. If the all pixels
have value with +/-1 from the edge pixel on the same side, the region
is treated as a "flat" region. For such case, a 7 tap filter is used
to change 3 pixel values on each side. The 7 taps are:
[1, 1, 1, 2, 1, 1, 1]/8
The furthest away pixels used as input are +/-5 away from edge. For
non-flat region, we fall back to old filtering. It should be noted
here that the thresholds and filter taps may require more optimization
for best possible results.
Tests on a set of hd clips showed consistent gains:
http://www.corp.google.com/~yaowu/no_crawl/mblpf_hd.html
(avg psnr: .83% glb psnr: .77% ssim: .82%)
Tests on derf set also showed consistent gains:
http://www.corp.google.com/~yaowu/no_crawl/mblpf_derf.html
(avg psnr: .24% glb psnr: .22% ssim: .48%)
Change-Id: I0855b1ff48e79e1175c20b81967137e18b2af352
Previously, the mode context is always udpated based on stats of current
frame, when there is no count, 50% is used for both left and right branch.
However, it is observed that with such strategy, a small count or no count
at all can skew the probability distribution significantly. This commmit
changed the mode_context update strategy to prevent small counts from
skewing the probability distributions.
Tests on derf set showed a small gain: .06% in psnr and .09% in ssim
Change-Id: Ic812e64ae5f70251c170b0717f7b7fa587055488
This commit extends the number of Q steps to 256 from 128.
The q_trans[] array has been altered to distribute available Q index values
(using the current 64 steps available as input parameters) evenly across the
available range. This is coupled with the fact that each Q step where possible
now equates to a fixed % change in the quantizer. This may want refinement
later especially in terms of the granularity at the high quality end but is a
reasonable starting point.
Change-Id: I2aaa6874fa10ce05c958dd182947ce39f6f1eecb
High Q end extended a little.
Some clean up.
Slightly better on SSIM, Slightly worse on PSNR over derf set.
Change-Id: I3dceea8a39e11c26e1a389a40e40b86efc76d28c
Added code to support 256 index steps instead of 128 but disabled for now.
Replace hard wired table vp8cx_base_skip_false_prob[128]
Observed Qindex problem with setting minimum loop filter value.
(Experiment code using real Q in place but for now just returning 0. This has a big
beneficial effect on some clips, particularly waterfall which shows 5% ssim gain)
Change-Id: I2f7117de8adc1797164c106aa13effc900a1467e
Previously, Y-adaptive UV intra coding only enabled on key frames in
UVINTRA experiment. This commit enabled the same coding for inter
frames, so the encoding of UV intra modes are consistent cross all
frame types. Tests on derf set showed a very small overall gain around
.04%:
http://www.corp.google.com/~yaowu/no_crawl/interUVintra.html
The gain looks to be reasonable given inta coded MBs is only a
small portion of MBs in inter frames.
Change-Id: Ic6fc261923f2c253f4a0c9f8bccf4797557b9e16
A previous commit 76feb965 made the vp8_mode_context adaptive on a frame
frame basis, this commit further made the coding context adaptive to two
frame types separately. Tests on derf set showed a further small gain on
all metrics: avg psnr 0.10%, glb psnr: 0.11%, ssim: 0.08%
http://www.corp.google.com/~yaowu/no_crawl/newNearMode_1209.html
Change-Id: I7b3e32ec8729de1903d14a3f1213f1624b78cdee
This commit removed the macro CONFIG_MULCONTEXT, which was used to
indicate the experiment code for using separate context for altref
and normal frames. This commit made the change fully merged in.
Change-Id: I525f927f68e2365d37b340ef23b836a136a4f70b
This commit removed the macro CONFIG_I8X8, which was used to indicate
the 8x8 intra prediction experiment, made the change fully merged in.
Change-Id: Iafa4443781ce6e83f5591c12ba615a0e92ce0ea0
vp8_mode_contexts[] is an entropy table used to code inter mode
choices. It was a fixed constant table. This commit made the entropy
context adaptive. Tests on derf set showed very good consistent gains
on all metrics: avg psnr .47%, overall psnr .46% and ssim .40%.
http://www.corp.google.com/~yaowu/no_crawl/newModeContext.html
Change-Id: Ia62b14485c948e2b74586118619c5eb2068b43b2
This patch introduces the concept of dual inter16x16 prediction. A
16x16 inter-predicted macroblock can use 2 references instead of 1,
where both references use the same mvmode (new, near/est, zero). In the
case of newmv, this means that two MVs are coded instead of one. The
frame can be encoded in 3 ways: all MBs single-prediction, all MBs dual
prediction, or per-MB single/dual prediction selection ("hybrid"), in
which case a single bit is coded per-MB to indicate whether the MB uses
single or dual inter prediction.
In the future, we can (maybe?) get further gains by mixing this with
Adrian's 32x32 work, per-segment dual prediction settings, or adding
support for dual splitmv/8x8mv inter prediction.
Gain (on derf-set, CQ mode) is ~2.8% (SSIM) or ~3.6% (glb PSNR). Most
gain is at medium/high bitrates, but there's minor gains at low bitrates
also. Output was confirmed to match between encoder and decoder.
Note for optimization people: this patch introduces a 2nd version of
16x16/8x8 sixtap/bilin functions, which does an avg instead of a
store. They may want to look and make sure this is implemented to
their satisfaction so we can optimize it best in the future.
Change-ID: I59dc84b07cbb3ccf073ac0f756d03d294cb19281
This commit added code to keep track of separate entropy contexts for
normal frames and alt ref frames. The underly assumption was that the
two type of frames have different entropy characteristics given they
typically have quite different quantization levels. By keeping entropy
contexts separate, it helps the entropy context distribution to be more
closely adapted to each frame type.
Tests on derf set showed a good and very consistent gain on all clips
on all metrics, avg psnr: 0.89%, overall psnr: 0.84% and ssim 0.93%.
http://www.corp.google.com/~yaowu/no_crawl/mulcontext.html
Change-Id: I15bc9697f6ff7829042911fe0c62930585d7e65d
This commit enabled the usage of 8x8 intra prediction modes on inter
frames. There are a few TODO items related to this: 1)baseline entropy
need be calibrated; 2)cost of UV need to be done more properly rather
than using decision only relying on Y; 3)Threshold for allowing picking
8x8 intra prediction should be lowered to lower than the B_PRED.
Even with all the TODOs, tests showed consistent gain on derf set ~0.1%
(PSNR:0.08% and SSIM:0.14%). It is assumed that 8x8 intra prediction
will help more on large resolution clips, especially with above TODOs
addressed.
Change-Id: I398ada49dfc32575cfab962a569c2885111ae3ba
Fixed some further QIndex related issues and replaced some tables
(eg zbin and rounding)
Also Added function (currently disabled by default) to populate the
main AC and DC quantizer tables. Using the original AC range the
resulting computed DC values give behavior broadly comparable
on the DERF set. That is not to say that the equations will hold good
over a more extended range. The purpose of this code is to make it
easier to experiment with further alterations to the Q range and distribution
of Q values plus the relative weights given to AC and DC.
The function find_fp_qindex() ensures that changes to the Q tables
are reflected in the value passed in to the first pass code.
Slight experimental adjustment to static segment Q offset.
Change-Id: I36186267d55dfc2a3d565d0cff7218ef300d1cd5
this commit is to add an variable in the macroblock level mode
info structure to track the transform size used in each MB, so
the information can be used later in the loop filter to change
how loop filter works on MBs with different transform sizes.
Change-Id: Id0eeaba6cc854c6d1be00ed8d237b3d9e250e447
Fixed bug in firspass.c call to vp8_initialize_rd_consts()
This was passing in vp8_dc_quant(cm->base_qindex, cm->y1dc_delta_q)
instead of (cm->base_qindex + cm->y1dc_delta_q).
It just so happens that for the value 26 used for cm->base_qindex in the
unextended Q case, the two give similar results. However, when using
the extended Q range the two are very different.
Also added more stats output and partly disabled another broken feature.
Change-Id: Iddf6cf5ea8467c44b7c133f38e629f6ba6f2581e
This is an experiment to include a mv contribution from last frame to
nearest and near mv definition. Initial test showed some small though
consistent gain.
latest patch slightly better result ~.13%-~.18%.
TODO: the entropy used to encode the mode choice, i.e. the mv counts
based conditional distribution of modes should be re-collected to
reflect this change, it is expected that there is some further gain
from that.
Change-Id: Ief1e284a36d8aa56b49ae5b360c91419ec494fa4
