This commit replaces zrun_zbin_boost, a method of biasing non-zero
coefficients following runs of zero-coefficients to be rounded towards
zero, with an explicit skip-block choice in the RD loop.
The logic is basically that if individual coefficients should be rounded
towards zero (from a RD point of view), the trellis/optimize loop should
take care of it. If whole blocks should be zero (from a RD point of
view), a single RD check is much more efficient than a complete
serialization of the quantization loop.
Quality change: derf +0.5% psnr, +1.6% ssim; yt +0.6% psnr, +1.1% ssim.
SIMD for quantize will follow in a separate patch. Results for other
test sets pending.
Change-Id: Ife5fa641163ac5150ac428011e87188f1937c1f4
This commit change the partition search order to allow checking of
rectangular partition to be done after square partitions. It also
added a speed feature to skip rectangular partition check when
NONE is better than SPLIT in RD sense.
This feature roughly speed up encoder by 1.5X with loss on compression
-0.91% on cif set
-0.56% on stdhd set
Change-Id: I0d2d06993041aa9ea9073fcc39c54f73a127dfa4
This commit enables configurable reference buffer pointer for intra
predictor. This allows later removal of spatial dependency between
blocks inside a 64x64 superblock in the rate-distortion optimization
loop.
Change-Id: I02418c2077efe19adc86e046a6b49364a980f5b1
Also tweaks to other features and experiments with
what is on and off at different speed settings.
Change-Id: I3e1d0be0d195216bf17c2ac5df67f34ce0b306b2
Renamed cpi->sf.first_step to cpi->sf.reduce_first_step_size
and changed its meaning such that it is a delta applied to
reduce the default first step size (>> x) in the motion search
rather than an absolute value.
The default first step size is already changed according to the image
dimensions (smaller for smaller images). cpi->sf.reduce_first_step_size
now applies a further correction from the default.
Change-Id: Ia94e08bc24c67b604831f980909af7e982fcd16d
This uses variance to split partition. Variance is calculated using
nearest mv, always from last ref frame.
Change-Id: Idd015b4a9aa3bc82591759eac239680c07496896
Reduces TX_SIZE contexts to 2 for each kind. The code is
cleaner and there is hardly any performance difference with
more than two contexts.
Results: almost neutral
Change-Id: I17656bd6db76224ae2856adf882504560e7dbaa4
Adds coding of transform size within a frame by use of context
of transform sizes selected in left and above blocks.
Also incorporates code for generating stats.
TODO: generate and incorporate new default stats
Change-Id: I6a7af099f6ad61d448521d9a51167aedaf638ed6
Refactors mbskip coding to be compatible with coding of the rest of
the symbols. Adds forward/backward adaptation and removes a lot of
the legacy code.
Results:
fast50: +1.6%
derfraw300: +0.317%
Change-Id: I395a2976d15af044d3b8ded5acfa45f6f065f980
With the removal of i4X4 and SPLIT_MV modes, the two entries for the
modes are no longer used. This patch remove the coding of the deltas.
Change-Id: Iea4eb500404ebe9706159380a03b8eca542fb4c3
Changes to the coding of transform sizes, along with forward
and backward probability updates.
Results:
derf300: +0.241%
Context based coding of transform sizes will be in a separate
patch.
Change-Id: I97241d60a926f014fee2de21fa4446ca56495756
Code intra/inter, then comp/single, then the ref frame selection.
Use contextualization for all steps. Don't code two past frames
in comp pred mode.
Change-Id: I4639a78cd5cccb283023265dbcc07898c3e7cf95
Split partition probabilities between keyframes and non-keyframes,
since they are fairly different. Also have per-blocksize interframe
y intramode probabilities, since these vary heavily between different
blocksizes.
Lastly, replace default probabilities for partitioning and intra modes
with new ones generated from current codec. Replace counts with actual
probabilities also.
Change-Id: I77ca996e25e4a28e03bdbc542f27a3e64ca1234f
Added structures to support independent rd thresholds
for different block sizes (and set experimental block
size correction factors).
Added structure to to allow dynamic adaptation of thresholds
per mode and per block size basis depending on how often
the mode/block size combination is seen (currently fixed factor).
Removed some unused variables.
TODO
- Adaptation of thresholds based on how often each mode chosen.
- The baseline mode values could also be adjusted based on
the block size (e.g. for a particular intra mode use a low threshold
for 4x4 prediction blocks but a relatively high value for 64x64.
Change-Id: Iddee65ff3324ee309815ae7c1c5a8584720e7568
Adds backward adaptation and differential forward updates of switchable
interpolation filter probabilities. Also adds some cosmetic cleanups
and minor fixes on mv_ref probabilities.
derfraw300: +0.353% (with most coming from switchable interp changes)
Change-Id: Ie2718be73528c945fd0d80cfd63ca2d9cb3032de
Fixes an issue with reducing branch cts in the encoder causing
a drop in performance. The bug was introduced in a previous
clean up patch.
Test: Went back to the offending patch, applied this same fix
to it, and checked that results are identical to the parent
of that patch.
Change-Id: I0bad8e2d930235d0284300fcebf836ceb56f2498
This commit enables iterative motion search for 4x4/4x8/8x4 block
size compound inter-inter prediction.
WIP: borg run testing
Change-Id: I2b318db4a03cdca5a8002b3fa6c0fa89b129288b
1. remove prediction mode conversion
2. unified bmode, same for key and non-key frame
3. set I4X4_PRED count for pdf to 0, as I4X4_PRED is no longer
coded ever. It is determined by ref_frame and block partition
Change-Id: If5b282957c24339b241acdb9f2afef85658fe47d
Also do per-partition motion vector referencing in <sb8x8 partitions,
and adjust mvref finding for sub8x8 partitions.
Change-Id: Id3ed1ed4d2a8910d11d327db6cc63b8eb79f941f
Cleans up the experiment. Actually uses reduced counts for backward
updates, and reduced number of probabilities in the context.
No change in bitstream when the experiment is on.
Between expt on and off:
derfraw300 is down only -0.062% (which is better than when expts
were run previously).
Change-Id: I55285a049a0c22810bdb42914212ab5a4f8521b5
This is a mostly-working implementation of an extra channel in the
bitstream. Configure with --enable-alpha to test. Notable TODOs:
- Add extra channel to all mismatch tests, PSNR, SSIM, etc
- Configurable subsampling
- Variable number of planes (currently always uses all 4)
- Loop filtering
- Per-plane lossless quantizer
- ARNR support
This implementation just uses the same contents as the Y channel
for the A channel, due to lack of content and general pain in
playing back 4 channel content. A later patch will use the actual
alpha channel passed in from outside the codec.
Change-Id: Ibf81f023b1c570bd84b3064e9b4b8ae52e087592