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
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
We leave it in rdopt.c as a local define for now - this can be removed
later. In all other places, we remove it, thereby slightly decreasing
the size of some arrays in the bitstream.
Change-Id: Ic2a9beb97a4eda0b086f62c039d994b192f99ca5
It remains as a local define in rdopt.c so we can distinguish between
split and non-split modes in the RD loop, but disappears outside that
scope in the codec.
Change-Id: I98c18fe5ab7e4fbd1d6620ec5695e2ea20513ce9
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
Move 4x4/4x8/8x4 partition coding out of experimental list.
This commit fixed the unit test failure issues. It also resolved
the merge conflicts between 4x4 block level partition and iterative
motion search for comp_inter_inter.
Change-Id: I898671f0631f5ddc4f5cc68d4c62ead7de9c5a58
This commit allows the rate-distortion optimization of intra coding
capable of supporting 8x4 and 4x8 partition settings.
It enables the entropy coding of intra modes in key frame using a
unified contextual probability model conditioned on its above/left
prediction modes.
Coding performance:
derf 0.464%
Change-Id: Ieed055084e11fcb64d5d5faeb0e706d30268ba18
The recursive partition type search is enabled down to 4x4, 4x8 and
8x4, followed by the corresponding rate-distortion optimization for
the per-partition encoding mode decisions.
The bit-stream writing/reading synchronized in supporting the
rectangular partition of 8x8 block.
This provides above 1% coding performance gains on derf.
To do next:
1. re-design the rate-distortion loop for inter prediction below 8x8.
2. re-design the rate-distortion loop for intra prediction below 4x4.
3. make the loop-filter aware of rectangular partition of 8x8 block.
4. clean the unused probability models.
5. update default probability values.
Change-Id: Idd41a315b16879db08f045a322241f46f1d53f20
Replace vp9_kf_default_bmode_counts structure with
direct default probabilities. The probability structure is
smaller and it removes the need to specify in the bitstream
how to convert the counts to probabilities.
Note that I have concerns still about the size and value of
the large intra mode context. This may cause problems for
HW but it also means we rely heavily on reverse update as
forwards update of a structure this size is problematic. I
intend to review this more generally in the next few days to
see if we can come up with a competitive solution that does
not rely on such a large context.
Change-Id: I0a36071079d5d26a57ab0e9fbf91af4199aa7984
This commit allows the rate-distortion optimization recursion
at encoder to go down to 4x4 block size. It deprecates the use
of I4X4_PRED and SPLITMV syntax elements from bit-stream
writing/reading. Will remove the unused probability models in
the next patch.
The partition type search and bit-stream are now capable of
supporting the rectangular partition of 8x8 block, i.e., 8x4
and 4x8. Need to revise the rate-distortion parts to get these
two partition tested in the rd loop.
Change-Id: I0dfe3b90a1507ad6138db10cc58e6e237a06a9d6
The number of reference buffers is extended to 8 and
a reference sign-bias added for the LAST_FRAME.
Whilst the number of reference buffers used by an
individual frame remains unchanged at 3, these may
now be selected from 8 possible buffers.
Change-Id: I2d247b9c1c2b3a339d6c9fac125e81ba373f75a7
Work-in-progress, not yet ready for review. TODO items:
- bitstream writing (encoder) and reading (decoder)
- decoder reconstruction
Change-Id: I5afb7284e7e0480847b47cd0097cb469433c9081
This commit enables selecting probability models for recursive block
partition information syntax, depending on its above/left partition
information, as well as the current block size. These conditional
probability models are reasonably stationary and consistent across
frames, hence the backward adaptive approach is used to maintain and
update the contextual models.
It achieves coding performance gains (on top of enabling rectangular
block sizes):
derf: 0.242%
yt: 0.391%
hd: 0.376%
stdhd: 0.645%
Change-Id: Ie513d9673337f0d27abd65fb566b711d0844ec2e
For 1080 material, this buffer is currently 2,270,928 bytes. This patch swaps
ptrs instead of copying and uses the last show_frame flag instead of setting
the entire buffer to zero. For the test clip used, the decoder improved by up
to 1%.
Change-Id: I686825712ad56043e09ada9808dc489f875a6ce0
Enable recursive partition information coding from SB64X64 down to
MB16X16. The bit-stream syntax is now supporting rectangular block
sizes. It starts from SB64X64 and recursively describes the partition
type of the current block. If the partition type is PARTITION_NONE,
the block is coded as a single unit; if it is PARTITION_HORZ or
PARTITION_VERT, the block is segmented into two independently coded
rectangular units, with no further partition needed; otherwise, the
block is segmented into 4 square blocks. i.e., PARTITION_SPLIT case,
each can be potentially further partitioned.
Forward adaptive probability modeling is used for the partition
information coding, conditioned on the current block size.
Change-Id: I499365fb547839d555498e3bcc0387d8a3587d87
To match the order of directional intra prediction modes for larger
blocks, also renamed the i4x4 prediction modes to mirror the larger
variants.
Change-Id: I77cea4d0add6c7758460bf9c7a2fe59aca601f0b
The previous implementation visited each node in the tree multiple times
because it used each symbol's encoding to revisit the branches taken and
increment its count. Instead, we can traverse the tree depth first and
calculate the probabilities and branch counts as we walk back up. The
complexity goes from somewhere between O(nlogn) and O(n^2) (depending on
how balanced the tree is) to O(n).
Only tested one clip (256kbps, CIF), saw 13% decoding perf improvement.
Note that this optimization should port trivially to VP8 as well. In VP8,
the decoder doesn't use this function, but it does routinely show up
on the profile for realtime encoding.
Change-Id: I4f2848e4f41dc9a7694f73f3e75034bce08d1b12
