This commit makes operations of the superblock intra coding rate
distortion optimization consistent with those used in the encoding
process. Given the test prediction mode and transform size, the rd
optimizer encodes and reconstructs each transformed block of the
superblock consecutively, then computes the total rate-distortion
costs accosicated with the current superblock to select the coding
decisions.

It achieves coding performance gains:
derf 0.353%
yt   1.111%

Change-Id: I0da2eb7a71361dfb8c1384927fc536b0c2790d07

Enable iterative motion search for compound inter-inter prediction
of block sizes 4x4/4x8/8x4 only when best coding quality is selected.
The iterative motion search provides about 0.1% gains for derf and
stdhd at this point, at the expense of longer runtime.

Change-Id: Idc03e7f827e51f1bb8d269bc3752ee297a6bbfe5

Change-Id: Ib557cc6351404b9e178e95a545883eb3666f11f0

Migrates costing changes/fixes from the rebalance expt to the head
without the expt on.

Rebased.

Change-Id: I51677d62f77ed08aca8d21a4c9a13103eb8de93f
Results:
derfraw300: +0.126%

Change-Id: I02c17fb733c0f3c22dc3167c3d3182797415f1ae

Change-Id: I2dfc569106b29fbe4da20585a0e85e5e9ea6a4db

This speed 1 - uses variance threshold stolen from static-thresh
to determine split.  Any superblock with greater than the variance
set by static thresh * quantizer index squared is split. In addition
transform size is set to largest size less than or equal to partition
size, sub pixel filter is set to normal,  and only 12 modes are used
at all.

Change-Id: If7a2858ee70f96d1eb989c04fd87a332b147abef

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

Also merge all counters. This removes a few unused probability updates
from the bitstream.

Change-Id: I20f58853e9dac84d8c0d9703ae012c55917516eb

This commit enables iterative motion search for 4x4/4x8/8x4 block
size compound inter-inter prediction.

WIP: borg run testing

Change-Id: I2b318db4a03cdca5a8002b3fa6c0fa89b129288b

This patch changes the coefficient tree to move the EOB to below
the ZERO node in order to save number of bool decodes.

The advantages of moving EOB one step down as opposed to two steps down
in the other parallel patch are: 1. The coef modeling based on
the One-node becomes independent of the tree structure above it, and
2. Fewer conext/counter increases are needed.

The drawback is that the potential savings in bool decodes will be
less, but assuming that 0s are much more predominant than 1's the
potential savings is still likely to be substantial.

Results on derf300: -0.237%

Change-Id: Ie784be13dc98291306b338e8228703a4c2ea2242

For 4x4 blocks valgrind points out the cache was uninitalized.
This resolves the issue by setting it.

Change-Id: I22733000da048643762813a84fbda66d8e4040d2

This commit makes clean-ups in the rate-distortion loop for 4x4,
4x8, and 8x4 block sizes for the use of iterative motion search.

Removed unnecessary use of bmi in handle_inter_mode.

Deprecated loop over labels in the 4x4/4x8/8x4 block rd search.

Change-Id: I71203dbb68b65e66f073b37abd90d82ef5ae6826

This patch checks at the frame level to see if the previous
mode info context can be used.  This patch eliminates the
flag check that was done for every mode and removes another
check that was done prior to every vp9_find_mv_refs().

Change-Id: I9da5e18b7e7e28f8b1f90d527cad087073df2d73

scales for second reference frame vars are unitialized if the
second ref frame is one of of those disallowed by refframeflags

Change-Id: I4ce42de391178c1699dcaede18c5f12c84993c61

Proposal for tuning the residual coding by changing how the context
from previous tokens is calculated. Storing the energy class of previous
tokens instead of the token itself eases the critical path of
HW implementations.

Change-Id: I6d71d856b84518f6c88de771ddd818436f794bab

Change-Id: Ic40d56fb162f4e201547dfae33e62ccd9e865889

This commit pulls the iterative motion search for compound inter-
inter out from handle_inter_mode_ as a separate function. Hence,
it is applicable to 4x4/4x8/8x4 level compound inter search to be
enabled later.

Also edit the rd loop for 4x4 inter block sizes for cosmetic
purpose.

Change-Id: Ibc71a11cbe5a26cd52faba01026cf8446cf4d2b4

Removed one 4x4 prediction step that was unnessary in the rd loop.
Removed a unused modecosts estimate from encoder side.

Change-Id: I65221a52719d6876492996955ef04142d2752d86

Change-Id: I81c637c61ecc33cb66beb59a2a33166d66b9a0a2

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

Change-Id: I07b8c15f33e6e7c63dd0033c18c4ac5c0303cf32

Also do per-partition motion vector referencing in <sb8x8 partitions,
and adjust mvref finding for sub8x8 partitions.

Change-Id: Id3ed1ed4d2a8910d11d327db6cc63b8eb79f941f

This commit fixed a uninitialized value use in the intra 4x4/8x4/4x8
rate-distortion loop.

Change-Id: I5c25b3536b59e4f5fbb23cf85baf93b2ccec7d72

This commit refactors the iterative motion search for compound
inter-inter mode, to make it support all partition types including
4x4/4x8/8x4 block sizes.

Change-Id: I5f1212b0f307377291763e45c6bdc9693b5f04c8

Removal from under configure flag.
A bit  renaming

Change-Id: I2213229dfe852001dfec16b149f47c52ce88f3aa

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

Reverts to using 128 bit LUT for the coef models rather than 48
to ease hardware implementation.

Also incorporates some cleanups including removing various
hooks to support different lookup tables based on block_type and
ref_type.

Change-Id: I54100c120cca07a2ebd3a7776bc4630fa6a153f6

Merge this experiment so that it is under a speed feature
flag not a configuration flag.

Change-Id: I536f7f125a4ff5149bb3a64f791e835c324535fd

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

Merges the experiment.

Change-Id: I4eb19af6de6df6aa3a96a2e82f231d47ed9b3ae9

Change-Id: I4f1a4eca6794cda78d00512196caacd5567e2dcc

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 patch eliminates the intermediate diff buffer usage by
combining the short idct and the add residual into one function.
The encoder can use the same code as well.

Change-Id: I296604bf73579c45105de0dd1adbcc91bcc53c22

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

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

These building blocks enable rate-distortion optimization search
over block sizes of 8x4 and 4x8. Need to convert them into mmx/sse
forms.

Change-Id: I570ea2d22d14ceec3fe3575128d7dfa172a577de

This commit allows proper transform type (DCT/ADST) selection in
the settings of partition 4x4 level.

Change-Id: Iec6f922a46480d777e7ca9142a99e8c131f0077b

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