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

Change-Id: I274a1d2e461e6ffdb106bac4ad6951692ace314e

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

Merge sb32x32 and sb64x64 functions; allow for rectangular sizes. Code
gives identical encoder results before and after. There are a few
macros for rectangular block sizes under the sbsegment experiment; this
experiment is not yet functional and should not yet be used.

Change-Id: I71f93b5d2a1596e99a6f01f29c3f0a456694d728

Update the code to call the new convolution functions to do subpixel
prediction rather than the existing functions. Remove the old C and
assembly code, since it is unused. This causes a 50% performance
reduction on the decoder, but that will be resolved when the asm for
the new functions is available.

There is no consensus for whether 6-tap or 2-tap predictors will be
supported in the final codec, so these filters are implemented in
terms of the 8-tap code, so that quality testing of these modes
can continue. Implementing the lower complexity algorithms is a
simple exercise, should it be necessary.

This code produces slightly better results in the EIGHTTAP_SMOOTH
case, since the filter is now applied in only one direction when
the subpel motion is only in one direction. Like the previous code,
the filtering is skipped entirely on full-pel MVs. This combination
seems to give the best quality gains, but this may be indicative of a
bug in the encoder's filter selection, since the encoder could
achieve the result of skipping the filtering on full-pel by selecting
one of the other filters. This should be revisited.

Quality gains on derf positive on almost all clips. The only clip
that seemed to be hurt at all datarates was football
(-0.115% PSNR average, -0.587% min). Overall averages 0.375% PSNR,
0.347% SSIM.

Change-Id: I7d469716091b1d89b4b08adde5863999319d69ff

Various fixups to resolve issues when building vp9-preview under the more stringent
checks placed on the experimental branch.

Change-Id: I21749de83552e1e75c799003f849e6a0f1a35b07

Change-Id: Ieefd76e164ca4aa87597da0412977614ddfbacb7

and some miscellaneous invoke left overs

Change-Id: I63191b1bfd3bea4ce30cceaeb686ec850570fc43

Support for gyp which doesn't support multiple objects in the same
static library having the same basename.

Change-Id: Ib947eefbaf68f8b177a796d23f875ccdfa6bc9dc

More cleanup to do after this,  but this is a good chunk of removing rtcd.

Change-Id: I551db75e341a0a85c3ad650df1e9a60dc305681a

Removed the rtcd subpixel invoke functions.

Change-Id: I8b7618bd5813333fac66b2817bdf807616e0fb33

Change-Id: Ib8f8a66c9fd31e508cdc9caa662192f38433aa3d

Similar to 16x16 dequant and idct, based on the value of eobs, the
8x8 dequant and idct calculation was simplified to improve decorder
performance.

Combined vp9_dequant_idct_add_8x8 and vp9_dequant_dc_idct_add_8x8
to eliminate duplicate code.

Change-Id: Ia58e50ab27f7012b7379c495837c9c0b5ba9cf7f

As suggested by Yaowu, simplified 16x16 dequant and idct. In decoder,
after detoken step, we know the number of non-zero dct coefficients
(eobs) in a macroblock. Idct calculation can be skipped or simplified
based on eobs, which improves the decoder performance.

Change-Id: I9ffa1cb134bcb5a7d64fcf90c81871a96d1b4018

Change-Id: Ic084c475844b24092a433ab88138cf58af3abbe4

Most of these were picked up by jenkins in the commit that changed
the vp8 namespace to vp9 in common/.

Change-Id: I5cbd56ffc753b92ef805133cda6acc1713a13878

For non-static functions, change the prefix to vp9_. For static functions,
remove the prefix. Also fix some comments, remove unused code or unused
function prototypes.

Change-Id: I1f8be05362f66060fe421c3d4c9a906fdf835de5

This change encompasses VP8_PTR, VP8_COMP, VP8D_COMP, VP8_COMMON,
VP8Decompressor and VP8Common.

Change-Id: I514ef4ad4e682370f36d656af1c09ee20da216ad

Change-Id: Ic5a5f60e1ff9d9ccae4174160d36529466eeb509

Change-Id: I446b2ffcbe732ffb112dbd97a4799272d4c01a84

This reinstates reverted commit 2113a831

Change-Id: I9a9af13497d1e58d4f467e3e083fddf06b1b786c

This reverts commit 2113a831

Code clean up - removed rtcd

Change-Id: Id963ecf53c370b1d99484ef18d6befeed7e0c748

Change-Id: I22aa803ffff330622cdb77277e7b196a9766f882

Convert copy16x16 from invoke to rtcd.  The first in a long
string of converts.

Change-Id: I296b0aa32f40e9fb649f7a3cb914a4e5300cad63

Enable ADST/DCT of dimension 16x16 for I16X16 modes. This change provides
benefits mostly for hd sequences.

Set up the framework for selectable transform dimension.

Also allowing quantization parameter threshold to control the use
of hybrid transform (This is currently disabled by setting threshold
always above the quantization parameter. Adaptive thresholding can
be built upon this, which will further improve the coding performance.)

The coding performance gains (with respect to the codec that has all
other configuration settings turned on) are

derf:   0.013
yt:     0.086
hd:     0.198
std-hd: 0.501

Change-Id: Ibb4263a61fc74e0b3c345f54d73e8c73552bf926

This commit adds a pick_sb_mode() function which selects the best 32x32
superblock coding mode. Then it selects the best per-MB modes, compares
the two and encodes that in the bitstream.

The bitstream coding is rather simplistic right now. At the SB level,
we code a bit to indicate whether this block uses SB-coding (32x32
prediction) or MB-coding (anything else), and then we follow with the
actual modes. This could and should be modified in the future, but is
omitted from this commit because it will likely involve reorganizing
much more code rather than just adding SB coding, so it's better to let
that be judged on its own merits.

Gains on derf: about even, YT/HD: +0.75%, STD/HD: +1.5%.

Change-Id: Iae313a7cbd8f75b3c66d04a68b991cb096eaaba6

Latest version of all scripts/makefile but rtcd_defs.sh is empty, all
existing functions are still selected using the old/current way.

Change-Id: Ib92946a48a31d6c8d1d7359eca524bc1d3e66174

Set on all 16x16 intra/inter modes

Features:
- Butterfly fDCT/iDCT
- Loop filter does not filter internal edges with 16x16
- Optimize coefficient function
- Update coefficient probability function
- RD
- Entropy stats
- 16x16 is a config option

Have not tested with experiments.

hd:     2.60%
std-hd: 2.43%
yt:     1.32%
derf:   0.60%

Change-Id: I96fb090517c30c5da84bad4fae602c3ec0c58b1c

Merged the enhanced_interp experiment.
Found and fixed a bug in the include files framework, whereby
certain encoder files were still using the old INTERP_EXTEND
value of 3 instead of 4. The thresholds for mv range mcomp.c
need a small adjustment to prevent crashes.

The results are more or less unchanged.

Change-Id: Iac5008390f1efc97ce1102fbb5f8989c847fb579

Approximate the Google style guide[1] so that that there's a written
document to follow and tools to check compliance[2].

[1]: http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml
[2]: http://google-styleguide.googlecode.com/svn/trunk/cpplint/cpplint.py

Change-Id: Idf40e3d8dddcc72150f6af127b13e5dab838685f

Avoid a pthreads dependency via pthread_once() when compiled with
--disable-multithread.

In addition, this synchronization is disabled for Win32 as well, even
though we can be sure that the required primatives exist, so that the
requirements on the application when built with --disable-multithread
are consistent across platforms.

Users using libvpx built with --disable-multithread in a multithreaded
context should provide their own synchronization. Updated the
documentation to vpx_codec_enc_init_ver() and vpx_codec_dec_init_ver()
to note this requirement. Moved the RTCD initialization call to match
this description, as previously it didn't happen until the first
frame.

Change-Id: Id576f6bce2758362188278d3085051c218a56d4a

Updates idct/dequant mmx assembly to work with vpnext instead of vp8.

Also adds x86inc.asm

Change-Id: I6e147d5e89177ae449271e97e50d082eb11b078e

Ensure that RTCD function pointers are set at most once, to silence
some data race warnings. Implementation provided for POSIX threads and
Win32, with the prior unsynchronized behavior left in place for other
platforms.

Change-Id: I65c5856df43ef67043b3d5f26ddafddd8fcb2f7e

Change-Id: I9d6083d54e3d478ec20dc6dc48d3f45eb5c7e16b

Change-Id: I0af3395500b1cb0ed629249eb6636a0c9322cb18

Various refactoring to make the subpel motion compensation
filters switchable by a frame level field.
Two types of 8-tap filters are supported in addition to the existing
bilinar and sixtap filters. One is the default 8-tap and the
other has a sharper cut-off for use with frames with substantial
edge content.

Patch 2: Added a preliminary strategy for filter selection based on
edginess detecton. Also includes some filter changes.

Change-Id: I866085bda5ae143cfdf2ec88157feaabdf7bd63a

This is a code snapshot of experimental work currently ongoing for a
next-generation codec.

The codebase has been cut down considerably from the libvpx baseline.
For example, we are currently only supporting VBR 2-pass rate control
and have removed most of the code relating to coding speed, threading,
error resilience, partitions and various other features.  This is in
part to make the codebase easier to work on and experiment with, but
also because we want to have an open discussion about how the bitstream
will be structured and partitioned and not have that conversation
constrained by past work.

Our basic working pattern has been to initially encapsulate experiments
using configure options linked to #IF CONFIG_XXX statements in the
code. Once experiments have matured and we are reasonably happy that
they give benefit and can be merged without breaking other experiments,
we remove the conditional compile statements and merge them in.

Current changes include:
* Temporal coding experiment for segments (though still only 4 max, it
  will likely be increased).
* Segment feature experiment - to allow various bits of information to
  be coded at the segment level. Features tested so far include mode
  and reference frame information, limiting end of block offset and
  transform size, alongside Q and loop filter parameters, but this set
  is very fluid.
* Support for 8x8 transform - 8x8 dct with 2nd order 2x2 haar is used
  in MBs using 16x16 prediction modes within inter frames.
* Compound prediction (combination of signals from existing predictors
  to create a new predictor).
* 8 tap interpolation filters and 1/8th pel motion vectors.
* Loop filter modifications.
* Various entropy modifications and changes to how entropy contexts and
  updates are handled.
* Extended quantizer range matched to transform precision improvements.

There are also ongoing further experiments that we hope to merge in the
near future: For example, coding of motion and other aspects of the
prediction signal to better support larger image formats, use of larger
block sizes (e.g. 32x32 and up) and lossless non-transform based coding
options (especially for key frames). It is our hope that we will be
able to make regular updates and we will warmly welcome community
contributions.

Please be warned that, at this stage, the codebase is currently slower
than VP8 stable branch as most new code has not been optimized, and
even the 'C' has been deliberately written to be simple and obvious,
not fast.

The following graphs have the initial test results, numbers in the
tables measure the compression improvement in terms of percentage. The
build has  the following optional experiments configured:
--enable-experimental --enable-enhanced_interp --enable-uvintra
--enable-high_precision_mv --enable-sixteenth_subpel_uv

CIF Size clips:
http://getwebm.org/tmp/cif/
HD size clips:
http://getwebm.org/tmp/hd/
(stable_20120309 represents encoding results of WebM master branch
build as of commit#7a159071)

They were encoded using the following encode parameters:
--good --cpu-used=0 -t 0 --lag-in-frames=25 --min-q=0 --max-q=63
--end-usage=0 --auto-alt-ref=1 -p 2 --pass=2 --kf-max-dist=9999
--kf-min-dist=0 --drop-frame=0 --static-thresh=0 --bias-pct=50
--minsection-pct=0 --maxsection-pct=800 --sharpness=0
--arnr-maxframes=7 --arnr-strength=3(for HD,6 for CIF)
--arnr-type=3

Change-Id: I5c62ed09cfff5815a2bb34e7820d6a810c23183c

Change-Id: I8e9b6b154e1a0d0cb42d596366380d69c00ac15f

Also remove duplicate build_intra_predictors_mby/uv().

Change-Id: I78607e7304952a9b962a5b25af9bb9c48692187b