Create a merge between the experimental development history and the
previously published snapshot.
Change-Id: If320df72a6bbefec53833626d08dbc9678be2d2d
This is to avoid a rare encoder/decoder mismatch for MB using SPLITMV
mode. In decoder, the UV mv can be determined to need clamp, but the
flag is never set in encoder motion vector selection process, and the
clamp is not done in encoding in encoder.
Change-Id: I60520d3f790354c7855dadf03f0978ea9b77e2c0
This commit adds lossless compression capability to the experimental
branch. The lossless experiment can be enabled using --enable-lossless
in configure. When the experiment is enabled, the encoder will use
lossless compression mode by command line option --lossless, and the
decoder automatically recognizes a losslessly encoded clip and decodes
accordingly.
To achieve the lossless coding, this commit has changed the following:
1. To encode at lossless mode, encoder forces the use of unit
quantizer, i.e, Q 0, where effective quantization is 1. Encoder also
disables the usage of 8x8 transform and allows only 4x4 transform;
2. At Q 0, the first order 4x4 DCT/IDCT have been switched over
to a pair of forward and inverse Walsh-Hadamard Transform
(http://goo.gl/EIsfy), with proper scaling applied to match the range
of the original 4x4 DCT/IDCT pair;
3. At Q 0, the second order remains to use the previous
walsh-hadamard transform pair. However, to maintain the reversibility
in second order transform at Q 0, scaling down is applied to first
order DC coefficients prior to forward transform, and scaling up is
applied to the second order output prior to quantization. Symmetric
upscaling and downscaling are added around inverse second order
transform;
4. At lossless mode, encoder also disables a number of minor
features to ensure no loss is introduced, these features includes:
a. Trellis quantization optimization
b. Loop filtering
c. Aggressive zero-binning, rounding and zero-bin boosting
d. Mode based zero-bin boosting
Lossless coding test was performed on all clips within the derf set,
to verify that the commit has achieved lossless compression for all
clips. The average compression ratio is around 2.57 to 1.
(http://goo.gl/dEShs)
Change-Id: Ia3aba7dd09df40dd590f93b9aba134defbc64e34
Added the ability to optionally filter the prediction data
when inter modes are selected (excludes SPLITMV, for now).
The mode selection loop considers both the filtered and
non-filtered prediction data when choosing mode. The filter
can be turned on/off at the frame-level, or signaled for
each MB.
Change-Id: I1b783c71d95a361ab36c761b07e8a6b06bc36822
Incorporates mv_ref, mbsplit and second_mv into the adaptive
entropy framework. The mv_ref framework has been modified from
before.
Adds some clean-ups and fixes.
Results with the adaptive entropy experiment are currently up by
+1.93% on derf; +2.33% std-hd and +1.87% yt-hd.
Fixed a nasty intermittent bug.
Change-Id: I4b1ac9f9483b48432597595195bfec05f31d1e39
This patch incorporates adaptive entropy coding of coefficient tokens,
and mode/mv information based on distributions encountered in a frame.
Specifically, there is an initial forward update to the probabilities
in the bitstream as before for coding the symbols in the frame, however
at the end of decoding each frame, the forward update to the
probabilities is reverted and instead the probabilities are updated
towards the actual distributions encountered within the frame.
The amount of update is weighted by the number of hits within each
context.
Results on derf/hd/std-hd are all up by 1.6%.
On derf, the most of the gains come from coefficients, however for the
hd and std-hd sets, the most of the gains come from the mode/mv
information updates.
Change-Id: I708c0e11fdacafee04940fe7ae159ba6844005fd
This commit is to remove two arrays, which contain the probabilities
of how likely each probability in coef_probs table is updated. The
commit changed to use a fixed number "252".
Surprisedly, the overall impact on quality is close to zero, which
basically says the two big static arrays are not helpful at all.
derf: -0.016%, -0.020%
std-hd: 0.000%, -0.013%
yt: -0.022%, +0.007%
yt-hd: -0.038%, +0.034%
Change-Id: Ifee94d28a37dcab4f1d2b994bd5b07575be42b72
This commit added the ability to accumulate the coef stats across
different encodings using an intermediate binary stats files. The
accumulation happens only the binary stats file exists in current
directory. The encoder needs to be built with "ENTROPY_STATS" to
allow the output. The commit also fixed a few formating issues in
output stats file.
Change-Id: Ib1a41180aa554845cf51e4421a230b128a3a82b4
Changes to calculation of sr_coded_error to include 0,0 case.
Experimental use of sr_coded_error in calculating correction factor
for estimating the allowable Q range.
Reinstated some code needed for calculating section_intra_rating.
Add flash detection in calculation of KF boost
Increased tolerance in testing candidate key frames (needed with
longer motion search as this tends to slightly increase inter %.
Zbin changes for 8x8.
Other minor adjustments, refactoring and bug fixes.
Reinstated some motion break out clauses in boost loop
as their removal hurt a few 50fps clips badly in the std set.
It may be possible to remove them again later if a better way
can be found of preventing overly long gf intervals.
Change-Id: Iee686d0c31072828bb1ccd2bc63f5f1c7c548ea2
Variables m & mi were being dereferenced when they might
hold invalid values.
The fix is simply to move these dereferences to after the
point at which mb_row and mb_col are tested for validity.
Change-Id: Ib16561efa9792dc469759936189ea379d374ad20
This fix addresses some problems with very complex clips like
handling of flashes on clips like crew (which was made worse
by an earlier patch (derf and std-hd)).
Most clips a small effect but some between 1 & 2%
Derf +0.039, +0.211%
YT +0.042, +0.083%
Change-Id: I65fc7c13afc31482040068544dd65b8808f5cb4a
Removed the local scaling factor est_max_qcorrection_factor
and related code to simplify estimateq calculation (little effect
anyway)
Cap range of total correction factor.
Slight change to break out case to turn off arf.
Change-Id: I748187737ba93cfadf016f3dfdf8d2741934067f
the commit fixed a number of compiling issues when some epxeriments
are turned on at the same time.
Change-Id: Idb15b215e2d2a7d25f2707f99ef55a34e7301ce7
The commit changed how baseline 8x8 coefficient probabilities are
initialized, to be consistent with the initialization of baseline
4x4 coefficient probabilities.
The commit does not have any effect on compression.
Change-Id: Ifb3902b5dc0b0c2e6dc3aa5d4a6589d528e58355
Remove dependency on amount and speed of motion as this
may not behave well across different image sizes.
Tweak impact of % inter.
Add in experimental adjustment based on relative quality of an
older second reference frame.
Cap range of decay values allowed.
Some small + effect on derf but -ve on yt & hd at this stage.
Change-Id: I390d6f6ebe67a2eb0b834980d0d4650124980d3e
I now see I didn't write a very long description, so let's do it
here then. We took a pretty big quality hit (0.1-0.2%) from my
recent fix of the inversion of arguments to vp8_cost_bit() in the
RD reference frame costing. I looked into it and basically the
costing prevented us from switching reference frames. This is of
course silly, since each frame codes its own prob_intra_coded, so
using last frame cost indications as a limiting factor can never
be right.
Here, I've rewritten that code to estimate costings based partially
on statistics from progress on current frame encoding. Overall,
this gives us a ~0.2%-0.3% improvement over what we had previously
before my argument-inversion-fix, and thus about ~0.4% over current
git (on derf-set), and a little more (0.5-1.0%) on HD/STD-HD/YT.
Change-Id: I79ebd4ccec4d6edbf0e152d9590d103ba2747775
