Commit Graph

92 Commits

Author SHA1 Message Date
Deb Mukherjee
57d953479b Adding contextual coding of mb_skip_coeff flag.
Using contextual coding of the mkb_skip_coeff flag using the
values of this flag from the left and above. There is a small
improvement of about 0.15% on Derf:
http://www.corp.google.com/~debargha/vp8_results/mbskipcontext.html

Refactored to use pred_common.c by adding a new context type.

Results on HD set (about 0.66% improvement):
http://www.corp.google.com/~debargha/vp8_results/mbskipcontext_hd.html

Incliding missing refactoring to use the pred_common utilities.

Change-Id: I95373382d429b5a59610d77f69a0fea2be628278
2012-03-21 03:55:44 -07:00
Yaowu Xu
21d3612a2f added clamp for 2nd motion vector
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
2012-03-14 18:53:26 -07:00
Paul Wilkins
68033ca472 Snapshot candidate
Pulled out super block code for the snapshot as this
is not quite ready and will need an extensive re-merge.

Change-Id: I436369b511257447a7b0ea064016cb63f5011849
2012-03-07 11:24:33 +00:00
Ronald S. Bultje
c3f5b2931b Use per-MB compound intra prediction.
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
2012-03-05 15:23:10 +00:00
Yaowu Xu
6898e8b7ab Changed how UV r/d estimates are done for Intra Modes
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
2012-03-05 13:16:41 +00:00
Ronald S. Bultje
921b1c3c94 Rename "dual" prediction to "compound" prediction.
Change-Id: Ibcd2b9b247ff9f83331dac47f91ec285e8955ff1
2012-02-28 17:43:46 -08:00
Ronald S. Bultje
d476165107 Compound intra prediction (b_pred/4x4 only, for now),
Also remove duplicate build_intra_predictors_mby/uv().

Change-Id: I78607e7304952a9b962a5b25af9bb9c48692187b
2012-02-28 17:41:03 -08:00
Deb Mukherjee
3e1cad9c69 Initial refactoring of high_precision mv code.
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
2012-02-28 15:09:20 -08:00
Deb Mukherjee
18e90d744e Supporting high precision 1/8-pel motion vectors
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
2012-02-23 09:25:21 -08:00
Paul Wilkins
46f9ad2ca5 Experimental code base simplification.
Remove error concealment code.

Change-Id: I882705174fbfea212e96f7f684e47a671dbe5c67
2012-02-15 16:08:47 +00:00
Ronald S. Bultje
29e4d7e861 Merge dualpred (compound prediction) experiment.
Change-Id: Ieaaa07c50eae41118596197f6a4d848135946e41
2012-02-09 16:29:18 -08:00
Paul Wilkins
d90f0eb4c5 Removal of SEGFEATURES placeholder comments
This commit only involves the removal of placeholder comments
//#if CONFIG_SEGFEATURES.

Change-Id: I94b350daaf998ee0cfdde5aa25b1d3b0522ab816
2012-02-09 17:25:05 +00:00
Paul Wilkins
cf8af867dd Merge COMPRED
Merged in most of the current common prediction changes
that were under the #if CONFIG_COMPRED option.

Change-Id: If4e6f61dbe7b86dd449f6effbe93b5eb7e893885
2012-02-09 16:10:46 +00:00
Paul Wilkins
8266abfe96 Dual pred flag
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
2012-02-09 15:44:18 +00:00
Paul Wilkins
9c9300f56f Merged NEWNEAR experiment
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
2012-02-06 16:40:57 +00:00
Paul Wilkins
82b865da94 Coding the hybrid dual prediction signal.
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
2012-02-06 16:38:41 +00:00
Paul Wilkins
c98e9d2882 Moved prob_dualpred to common.
Moved the prob_dualpred[] sturcture to common.
Created common prediction entry for Dual flag.

Change-Id: I9ac3d128bae6114f09e5c18216d4b95cf36453d5
2012-02-06 16:37:11 +00:00
Paul Wilkins
58ec6fe8c3 Modified prediction behavior for reference frame.
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
2012-02-06 16:34:41 +00:00
Paul Wilkins
f0459549a6 Reference frame prediction:
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
2012-02-03 12:44:45 +00:00
Adrian Grange
5d0b5a17d9 Added encoding in Superblock Order
As a precursor to encoding 32x32 blocks this cl adds the
ability to encode the frame superblock (=32x32 block) at
a time. Within a SB the 4 indiviual MBs are encoded in
raster-order (NW,NE,SW,SE).

This functionality is added as an experiment which can be
enabled by ispecifying --enable-superblocks in the
command line specified to configure (CONFIG_SUPERBLOCKS
macro in the code).

To make this work I had to disable the two intra
prediction modes that use data from the top-right of the
MB.

On the tests that I have run the results produce
almost exactly the same PSNRs & SSIMs with a very
slightly higher average data rate (and slightly higher
data rate than just disabling the two intra modes in
the original code).

NOTE: This will also break the multi-threaded code.

This replaces the abandoned change:
Iebebe0d1a50ce8c15c79862c537b765a2f67e162

Change-Id: I1bc1a00f236abc1a373c7210d756e25f970fcad8
2012-02-02 10:30:57 -08:00
Yaowu Xu
27cca3dd94 Fixes a decoder bug
The bug was introduced by the commit that added I8X8 intra prediction
mode for inter frames, the decoder was not update to accept the additional
probability update from encoder. This causes the decoder typicall to crash
when encoder sends intra mode probability update.

Change-Id: Ib7dc42dc77a51178aa9ece41e081829818a25016
2012-02-01 14:56:14 -08:00
Author: John Koleszar
d24de592a6 Import another decoder bug fix from public stable branch
Please see the following for details:
https://gerrit.chromium.org/gerrit/#change,10925

Change-Id: Ie692261c255c58d7762df22eeca566a7d13adcba
2012-02-01 14:56:12 -08:00
Paul Wilkins
1335ac3071 Implementation of new prediction model for reference frame coding.
This check in uses the common prediction interface functions
to code reference frame.

Some updates made regarding the impact of the new code in rd loop
but there remain TODOs in this regard.

Change-Id: I9da3ed5dfdaa489e0903ab33258b0767a585567f
2012-01-31 12:54:05 +00:00
Paul Wilkins
56904be19d Use common prediction interface for segment coding.
This does not change any functionality just modifies the code to
use the common prediction module interface for coding
the segment data.

Change-Id: Ifd43e9153573365619774a4f5572215e44fb5aa3
2012-01-31 12:53:49 +00:00
Paul Wilkins
5f0f260f0c Moved some reference frame data structures into common.
In this commit only the decoder side was updated.

Change-Id: Ia9bd58da07d1a943f028e330f0489344e62b0d02
2012-01-31 12:52:33 +00:00
Paul Wilkins
fe96afa705 Moved some segmentation data structures.
Moved some segmentation data structures into VP8_COMMON

Change-Id: I59c6e2edf7a0176e35319936eea450027aeb3b39
2012-01-31 12:51:57 +00:00
Adrian Grange
0fafd0543f Reset segment_id to 0 when segmentation is disabled
Whilst the encoder explicitly set the segment_id to 0
when segmentation is diabled, the decoder would allow
the segment_id to persist from the previous frame.

This fix attempts to make the decoder behave the same
as the encoder by explicitly setting the segment_id to
0 in this case.

Change-Id: I65c3a05247550edb10706eb5d54d306dfb792309
2011-12-16 14:00:36 -08:00
Adrian Grange
ae63ce248a Fixed bug to use mode_info_stride rather than mb_cols
Both encoder & decoder were using mb_cols to
offset from one row of MODE_INFO structures to the next
when they should have been using mode_info_stride.

Fixing this in both encoder and decoder gives around
a 3KB size saving and 0.025dB PSNR improvement on the one
720P clip I tried.

(Also removed "index" which was being updated but not used)

Change-Id: I413bea802b142886bfcf8d8aa7f5a2f0c524fd4b
2011-12-15 10:00:46 -08:00
Yaowu Xu
be360d47f4 Enabled adaptive UV intra coding for inter frames
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
2011-12-09 14:44:13 -08:00
Yaowu Xu
d37cd97682 Removed #if CONFIG_I8X8
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
2011-12-07 13:48:53 -08:00
Yaowu Xu
76feb965d3 made vp8_mode_context adaptive
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
2011-12-07 11:01:59 -08:00
Paul Wilkins
79774d108f Minor fixes:
fixed issues caused by conflicts between two experiments.

Change-Id: I56a9bd69493e4850c121ea057a6233c55777c2a5
2011-12-07 09:55:27 -08:00
Ronald S. Bultje
60cb39da86 Dual 16x16 inter prediction.
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
2011-12-06 11:53:02 -08:00
Yaowu Xu
acf5d20ce5 added separate entropy context for alt_ref
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
2011-12-02 14:43:33 -08:00
Yaowu Xu
a8fbab8697 enabled 8x8 intra prediction modes on inter frames
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
2011-12-02 13:44:47 -08:00
Yaowu Xu
643238a3e0 changed find_near_mvs search to include a mb from last frame
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
2011-11-28 08:52:08 -08:00
Paul Wilkins
54f090b119 Cosmetic clean up.
Clean up of vp8_kfread_modes().
Remove unnecessary indentation and enforce line length.

Change-Id: I0864d1aff55368126db01bb23efa815786b5245d
2011-11-21 15:51:21 +00:00
Paul Wilkins
19d87e8ed7 Decoder segmentation bug.
Fix decoder segmentation bug for temporal coding where the segment map
was first initialized on a key frame.

in vp8_kfread_modes() after reading the segment id it must be written to
the  pbi->segmentation_map[] for use in temporal coding on subsequent frames.

Change-Id: I1489305efc376564e734a216f69c2844646ee3d3
2011-11-21 15:49:47 +00:00
Paul Wilkins
3cdfdb55e4 Merge CONFIGURE_SEGMENTATION experiment.
Removal of CONFIGURE_SEGMENTATION ifdefs.

Removal of legacy support code fo the old coding mechanism.

Use local reference "xd" for MACROBLOCKD structure in
encode_frame_to_data_rate()

Moved call to choose_segmap_coding_method() out of encode
loop as the cost of segmentation is not properly accounted
in the loop anyway. If this is desirable in the future it
can be moved back. The use of this function to do all the
analysis and set the probabilities also removes the need
to track segment useage in threading code.

Change-Id: I85bc8fd63440e7176c73d26cb742698f9b70cade
2011-11-15 16:15:23 +00:00
Paul Wilkins
6394ef28d7 Further clean up of Segmentation experiment code
Changed name and sense of segment_flag to "seg_id_predicted"
Added some additional comments and retested.

I also did some experimentation with a spatial prediction option
using a similar strategy to the temporal mode implemented.
This helps in some cases where temporal prediction is bad but
I suspect there is more overlap here with work on a larger scale
block structure and spatial correlation will likely be better
handled through that mechanism.

Next check in will remove #ifdefs and legacy mode code.

Change-Id: I3b382b65ed2a57bd7775ac0f3a01a9508a209cbc
2011-11-15 15:22:26 +00:00
Paul Wilkins
661b2c2dcf Further work on Segmentation Experiment:
This check in includes quite a lot of clean up and refactoring.

Most of the analysis and set up for the different coding options for the
segment map (currently simple distribution based coding or temporaly
predicted coding), has been moved to one location (the function
choose_segmap_coding_method() in segmenation.c). This code was previously
scattered around in various locations making integration with other
experiments and modification / debug more difficult.

Currently the functionality is as it was with the exception that the
prediction probabilities are now only transmitted when the temporal
prediction mode is selected.

There is still quite a bit more clean up work that will be possible
when the #ifdef is removed. Also at that time I may rename and alter
the sense of macroblock based variable "segment_flag" which indicates
(1 that the segmnet id is not predicted vs 0 that it is predicted).

I also intend to experiment with a spatial prediction mode that can be
used when coding a key frame segment map or in cases where temporal
prediction does not work well but there is spatial correlation.

In a later check in when the ifdefs have gone I may also move the call
to choose_segmap_coding_method() to just before where the bitsream is
packed (currently it is in vp8_encode_frame()) to further reduce the
possibility of clashes with other experiments and prevent it being called
on each itteration of the recode loop.

Change-Id: I3d4aba2a2826ec21f367678d5b07c1d1c36db168
2011-11-15 11:13:33 +00:00
Paul Wilkins
bf25d4ad7f SEGMENTATION experiment:
Some initial cleanup to aid testing and debug.

Pull code to choose temporal or spatial encoding
out of encodeframe.c into a dedicated function
in segmentation.c.

For now disable broken temporal mode.

Move the coding of "temporal_update" flag and
only transmit if segment map update is indicated.

Rename the functions read_mb_features() and
write_mb_features() to read_mb_segid() and
read_mb_segid() as they only read and write
the macroblock segment id not any of the
features.

Change-Id: Ib75118520b1144c24d35fdfc6ce46106803cabcf
2011-11-11 18:31:21 +00:00
Paul Wilkins
a258bba1fb Segment Feature Data Access
No change to functionality or output.

Updates to the segment feature data structure now all done
through functions such as set_segdata() and get_segdata()
in seg_common.c.

The reason for this is to make changing the structures (if needed)
and debug easier.

In addition it provides a single location for subsequent addition
of range and validity checks. For  example valid combination of
mode and reference frame.

Change-Id: I2e866505562db4e4cb6f17a472b25b4465f01add
2011-11-04 10:42:12 +00:00
Yaowu Xu
2bbde25003 make uv intra mode coding adaptive to Y mode
This commit tries to do UV intra mode coding adaptive to Y intra mode.
Entropy context is defined as conditional PDF of uv intra mode given
the Y mode. All constants are normalized with 256 to be fit in 8 bits.

This provides further coding efficiency beyond the quantizer adaptive
y intra mode coding. Consistent gains were observed on all clips and
all bit rates for HD all key encoding tests.

To test, configure with
--enable-experimental --enable-uvintra

Change-Id: I2d78d73f143127f063e19bd0bac3b68c418d756a
2011-11-03 21:48:08 -07:00
Paul Wilkins
a10a268e58 Segment Features. Removal of #ifdefs
Removal of configure #ifdefs so that segment features
always available. Removal of code supporting old
segment feature method.

Still a good deal of tidying up to do.

Change-Id: I397855f086f8c09ab1fae0a5f65d9e06d2e3e39f
2011-11-03 17:14:26 +00:00
Paul Wilkins
87ff8620b2 Segmentation: Reference frames
Modify reference frame segmentation so that ONE or MORE
reference frames may be marked as a available for a given
segment.

Fixed bugs relating to segment coding of INTRA and some
INTER modes at the segment level.

Modified Q boost for static areas based on ambient average Q.

Strong results now on clips with significant static areas.
(some data points in derf set as high as 9% and some static &
slide show type content in YT set > 20%)

Change-Id: Ia79f912efa84b977f35a23683ae3643251e24f0c
2011-11-02 13:31:54 +00:00
Paul Wilkins
01ce04bc06 Further segment feature extensions.
This quite large check in includes the following:

Merge in some code from Ronald (mbgraph.c) that scans a Gf/arf group.
This is used as a basis for a simple segmentation for the normal frames
in a gf/arf group. This code also uses satd functions from Yaowu.

Adds functionality for coding the latest possible position of an EOB for
blocks in the segment. (Currently 0-15 only, hence just for 4x4 dct).
Where the EOB position is 0 this acts like "skip" and the normal coding
of skip at the per mb level is disabled.

Added functions (seg_common.c) for setting and reading segment feature
elements. These may want to be optimized away at some point but while the
mecahnism is in a state of flux they provide a single location for making
changes and keep things a bit cleaner.

This is still proof of concept code. Currently the tested feature set:-

Quantizer,
Loop Filter level,
Reference frame,
Prediction Mode,
EOB end stop.

TBD:-

Add functions for setting and reading the feature data with range
and validity checking.

Handling of signed and unsigned feature data. At the moment all is assumed
to be signed and a sign bit is coded but many cannot be negative.

Correct handling of EOB feature with intra coded blocks.

Testing/trapping of legal/illegal ref frame and mode combinations.

Transform size switch plus merge and test with 8c8 DCT work

Merge and test with Sumans Segmenation coding optimizations

Change-Id: Iee12e83661c7abbd1e0ce6810915eb4ec35e2d8e
2011-10-24 15:52:18 +01:00
Paul Wilkins
156b221a7f Segment coding of mode and reference frame.
Proof of concept test code that encodes mode and reference
frame data at the segment level.

Decode-able bit stream but some issues not yet resolved.
As it this helps a little on a couple of clips but hurts on most as
the basis for segmentation is unsound.

To build and test, configure with
--enable-experimental --enable-segfeatures

Change-Id: I22a60774f69273523fb152db8c31f4b10b07c7f4
2011-09-30 16:45:16 +01:00
Yaowu Xu
1d44e7ce1f enable selecting&transmitting to for intra mode entropy
This commit added a 3 bit index to the bitstream, the index is used to
look into the intra mode coding entropy context table. The commit uses
the mode stats to calculate the cost of transmitting modes using 8
possible entropy distributions, and selects the distribution that
provides the lowest cost to do the actual mode coding.

Initial test show this provides additional .2%~.3% gain over quantizer
adaptive intra mode coding. So the adaptive intra mode coding provides
a total of .5%(psnr) to .6% gain(ssim) combined for all-key-encoding

To build and test, configure with
--enable-experimental --enable-qimode

Change-Id: I7c41cd8bfb352bc1fe7c5da1848a58faea5ed74a
2011-09-16 16:33:19 -07:00
Yaowu Xu
aac2c12663 add quantizer adaptive intra mb mode encoding
make intra mode coding entropy distribution adaptive to baseQindex, an
encoding test on hd clips with all key frame shows universal gain on
all clips in both .2%(psnr) and (ssim).3%.

To build and test, configure with
--enable-experimental --enable-qimode

Change-Id: Iaa69241b984d4fdd8baa6d77ee78c0140f5ac00a
2011-09-16 16:26:35 -07:00