This commit re-works the entropy coding scheme of the motion
compensated prediction modes. It allows more flexible hyperplane
partition for precise classification.
Change-Id: Iba5035c76691946cf1386b6c495e399c3d9c8fc5
Reduces the transform optons for INTRA as well as INTER when
transform size is 16x16 to not use any of the DSTs.
Thus, a total of 10 options are used for 16x16, while 4x4
and 8x8 still uses 17 options.
derflr/hevchd actually improves a little, while hevcmr drops
a little.
About 10% speed improvement.
Change-Id: I920a182231e052cdd622f8bb67085c16c572cb1e
Under the experiment of EXT_REFS: LAST2_FRAME, LAST3_FRAME, and
LAST4_FRAME.
Coding efficiency: derflr +1.601%; hevchr +1.895%
Speed: Encoder slowed down by ~75%
Change-Id: Ifeee5f049c2c1f7cb29bc897622ef88897082ecf
Remove MISC_FIXES flags except for the changes on MV precision, which
has a 0.1% performance drop.
On derflr, the impact is -0.012%.
Change-Id: I0a74e5a212dd0cb827192a318c92a714c9681e45
Adds a new interpolation experiment.
Improves entropy coding to send the filter type only if
the motion vectors have subpel components.
Adds one new 8-tap smooth filter, and tweaks the others.
derflr: +0.695%
hevcmr: +0.305%
About 5% encode slowdown. No visible impact for decoding.
Also makes the interpolation framework flexible to support both
strictly interpolating filters as well as non-interpolating
filters that filter integer offsets. This is mainly for
further experimentation and if not found useful the code will
be removed.
Change-Id: I8db9cde56ca916be771fe54a130d608bf10786e6
Currently there are two parts in this experiment: extra directional intra
prediction modes and the filter intra modes migrated from the nextgen branch.
Several macros are defined in "blockd.h" to provide controls of the experiment
settings. Setting "DR_ONLY" as 1 (default is 0) means we only use directional
modes, and skip the filter-intra modes; "EXT_INTRA_ANGLES" (default is 128)
defines the number of different angles we want to support; setting
"ANGLE_FAST_SEARCH" as 1 (default is 1) means we use fast sub-optimal search
for the best prediction angle, instead of exhaustive search. The fast search
is about 6 times faster than the exhaustive search, while preserving about
60% of the coding gains.
With extra directional prediction modes (fast search), we observe the following
code gains (number in parentheses is for all-key-frame setting):
derflr +0.42% (+1.79%)
hevclr +0.78% (+2.19%)
hevcmr +1.20% (+3.49%)
stdhd +0.56%
Speed-wise, about 110% slower for key frames, and 30% slower overall.
The gains of filter intra modes mostly add up with the gains of directional
modes. The overall coding gain of this experiment:
derflr +0.94%
hevclr +1.46%
hevcmr +1.94%
stdhd +1.58%
Change-Id: Ida9ad00cdb33aff422d06eb42b4f4e5f25df8a2a
Correctly compute the block size in bit-stream coefficient token
packing. This fixes an enc/dec mismatch at very high bit-rates.
Change-Id: I37bf084731dc660df0c695cad406ddcd0f9eb904
If a block has all coefficients quantized to zero, the codec will
assume that it uses largest transform block size.
Change-Id: Icd4e8e7cdc4b6af6974f87169e50b040ebfe9020
Allows inter and intra tx_types to have different sets of
transforms for different tx_size/sb_type combinations.
Change-Id: Ic0ac1daef7a9fb15c4210271e4d04cd36e5cec8e
This commit makes the coefficient token packtization process account
for variable transform block sizes supported in a single processing
block. It fixes an enc/dec mismatch issue when var-tx, ext-tx, and
misc-fixes experiments are all turned on.
Change-Id: I2e8946e6f72de567603a568debbadad11196430c
Some more testing of this patch would probably be useful, but I
think the basics of it should work fine now.
See issue 1035.
Change-Id: I4a36d58f671c5391cb09d564581784a00ed26245
This has various benefits:
- simplify implementations because we don't have to switch between
multiple probability tables depending on frametype
- allows fw subexp and bw adaptivity for partitions/uvmode in keyframes
See issue 1040 point 5.
Change-Id: Ia566aa2863252d130cee9deedcf123bb2a0d3765
Locate them (code-wise) in frame_context, and have them be updated
as any other probability using the subexp forward and adaptive bw
updates.
See issue 1040 point 1.
TODOs:
- real-world default probabilities
- why is counts sometimes NULL in the decoder? Does that mean bw
adaptivity updates only work on some frames? (I haven't looked
very closely yet, maybe this is a red herring.)
Change-Id: I23b57b4e5e7574b75f16eb64823b29c22fbab42e
Account for rounding in distortion calculation in k-means;
carry out rounding before duplicates removal of base colors;
replace numbers with macros;
use prefix increment.
Slight coding gain (<0.1%) on screen_content testset.
Change-Id: Ie8bd241266da6b82c7b2874befc3a0c72b4fcd8c
Add palette mode for keyframe luma channel. Palette mode is enabled
when using "--tune-content=screen" in encoding config parameters.
on screen_content testset: +6.89%
on derlr : +0.00%
Design doc (WIP):
https://goo.gl/lD4yJw
Change-Id: Ib368b216bfd3ea21c6c27436934ad87afdaa6f88
This commit re-designs the bitstream syntax to support recursive
transform block partition. The initial stage targets the inter
prediction residuals.
Change-Id: I556ab3c68c198387a2fd2d02e2b475e83cd417c3
We have historically added new bits to cat6 whenever we added a new
transform size (or bitdepth, for that matter). However, we have
always coded these new bits regardless of the actual transform size,
which means that for smaller transforms, we code bits that cannot
possibly be set. The coding (quality) impact of this is negligible,
but the bigger issue is that this allows creating bitstreams with
coefficient values that are nonsensible and can cause int overflows,
which then de facto become part of the bitstream spec. By not coding
these bits, we remove this possibility.
See issue 1065.
Change-Id: Ib3186eca2df6a7a15ddc60c8b55af182aadd964d
See issue 1051. 6 bits is fairly arbitrary but at least allows writing
delta Q values that are fairly normal in other codecs. I can extend to
8 if people want full range, although I personally don't have any need
for that.
Change-Id: I0a5a7c3d9b8eb3de4418430ab0e925d4a08cd7a0
