Adds differential encoding of prob updates using a subexponential
code centered around the previous probability value.
Also searches for the most cost-effective update, and breaks
up the coefficient updates into smaller groups.

Small gain on Derf: 0.2%

Change-Id: Ie0071e3dc113e3d0d7ab95b6442bb07a89970030

This is the first patch to add superblock (32x32) coding
order capabilities. It does not yet do any mode selection
at the SB level, that will follow in a further patch.

This patch encodes rows of SBs rather than
MBs, each SB contains 2x2 MBs.

Two intra prediction modes have been disabled since they
require reconstructed data for the above-right MB which
may not have been encoded yet (e.g. for the bottom right
MB in each SB).

Results on the one test clip I have tried (720p GIPS clip)
suggest that it is somewhere around 0.2dB worse than the
baseline version, so there may be bugs.

It has been tested with no experiments enabled and with
the following 3 experiments enabled:
  --enable-enhanced_interp
  --enable-high_precision_mv
  --enable-sixteenth_subpel_uv
in each case the decode buffer matches the recon buffer
(using "cmp" to compare the dumped/decoded frames).
Note: Testing these experiments individually created
errors.

Some problems were found with other experiments but it
is unclear what state these experiments are in:
  --enable-comp_intra_pred
  --enable-newentropy
  --enable-uvintra

This code has not been extensively tested yet, so there
is every likelihood that further bugs remain. I also
intend to do some code cleanup & refactoring in tandem
with the next patch that adds the 32x32 modes.

Change-Id: I1eba7f740a70b3510df58db53464535ef881b4d9

Using contextual coding of the mkb_skip_coeff flag using the
values of this flag from the left and above. There is a small
improvement of about 0.15% on Derf:
http://www.corp.google.com/~debargha/vp8_results/mbskipcontext.html

Refactored to use pred_common.c by adding a new context type.

Results on HD set (about 0.66% improvement):
http://www.corp.google.com/~debargha/vp8_results/mbskipcontext_hd.html

Incliding missing refactoring to use the pred_common utilities.

Change-Id: I95373382d429b5a59610d77f69a0fea2be628278

Pulled out super block code for the snapshot as this
is not quite ready and will need an extensive re-merge.

Change-Id: I436369b511257447a7b0ea064016cb63f5011849

Also remove duplicate build_intra_predictors_mby/uv().

Change-Id: I78607e7304952a9b962a5b25af9bb9c48692187b

Merge of the NEWLPF configuration experiment so it is always on.

Change-Id: I7054772b6eab28bad1ff807bfa54d98f83de9308

This is the initial patch for supporting 1/8th pel
motion. Currently if we configure with enable-high-precision-mv,
all motion vectors would default to 1/8 pel. Encode and
decode syncs fine with the current code. In the next phase
the code will be refactored so that we can choose the 1/8
pel mode adaptively at a frame/segment/mb level.

Derf results:
http://www.corp.google.com/~debargha/vp8_results/enhinterp_hpmv.html
(about 0.83% better than 8-tap interpoaltion)

Patch 3: Rebased. Also adding 1/16th pel interpolation for U and V

Patch 4: HD results.
http://www.corp.google.com/~debargha/vp8_results/enhinterp_hd_hpmv.html
Seems impressive (unless I am doing something wrong).

Patch 5: Added mmx/sse for bilateral filtering, as well as enforced
use of c-versions of subpel filters with 8-taps and 1/16th pel;
Also redesigned the 8-tap filters to reduce the cut-off in order to
introduce a denoising effect. There is a new configure option
sixteenth-subpel-uv which will use 1/16 th pel interpolation for
uv, if the motion vectors have 1/8 pel accuracy.

With the fixes the results are promising on the derf set. The enhanced
interpolation option with 8-taps alone gives 3% improvement over thei
derf set:
http://www.corp.google.com/~debargha/vp8_results/enhinterpn.html

Results on high precision mv and on the hd set are to follow.

Patch 6: Adding a missing condition for CONFIG_SIXTEENTH_SUBPEL_UV in
vp8/common/x86/x86_systemdependent.c

Patch 7: Cleaning up various debug messages.

Patch 8: Merge conflict

Change-Id: I5b1d844457aefd7414a9e4e0e06c6ed38fd8cc04

Remove error concealment code.

Change-Id: I882705174fbfea212e96f7f684e47a671dbe5c67

This commit moved segment based loop filter level selection into
the experiment of CONFIG_FEATUREUPDATES. As previous commit noted,
the segment based loop filter selection helps the compression by
~0.1% on cif set, the ongoing experiment CONFIG_FEATUREUPDATES
made encoding updates of the segment based LPF level more efficient,
hence, another .04% gain on cif set. The commit also fixed an issue
previously where encoder/decoder may use different loop filter level
for one of the segments.

Change-Id: Ia978b14aae95bb107d561ba53a7a2bb6ff01faf3

Removed ~CONFIG_REALTIME_ONLY code.

Change-Id: I5fafff29a08acd8928699f9ddce8744787024d8c

Added a bit to signify that the feature changed since
the last time we sent it, or not so that we don't need
to send all the databits for every feature change.

added config

Change-Id: I8d3064ce90d4500bf0d5c6b87c664e46138dfcac

For the experimental branch we are trying to slim the codebase
down removing features such as threading for now which complicate
the process of development and testing.

Change-Id: I657c0246aef4d1fa8c8ffc6a1adfeee45bce8e24

Change-Id: Ieaaa07c50eae41118596197f6a4d848135946e41

As a precursor to encoding 32x32 blocks this cl adds the
ability to encode the frame superblock (=32x32 block) at
a time. Within a SB the 4 indiviual MBs are encoded in
raster-order (NW,NE,SW,SE).

This functionality is added as an experiment which can be
enabled by ispecifying --enable-superblocks in the
command line specified to configure (CONFIG_SUPERBLOCKS
macro in the code).

To make this work I had to disable the two intra
prediction modes that use data from the top-right of the
MB.

On the tests that I have run the results produce
almost exactly the same PSNRs & SSIMs with a very
slightly higher average data rate (and slightly higher
data rate than just disabling the two intra modes in
the original code).

NOTE: This will also break the multi-threaded code.

This replaces the abandoned change:
Iebebe0d1a50ce8c15c79862c537b765a2f67e162

Change-Id: I1bc1a00f236abc1a373c7210d756e25f970fcad8

This function adds the common prediction modules,  some data structures
and a config option but does not use them.

It also corrects a bug in clearing down  the MODE_INFO border and introduces
a new element that indicates if an entry corresponds to an "in image" macro block
or is part of the border.

Change-Id: Ib69eec0876173ebe9d1de9df9537d0b2447702e0

using an 8-tap filter.

The results with 3 different 8-tap filters on the derf set are in:
http://www.corp.google.com/~debargha/vp8_results/enhinterp.html
The one that gives the most gain achieves an overall gain of about
0.6%. The results for a set of 12 hd (720p) videos are in:
http://www.corp.google.com/~debargha/vp8_results/enhinterp_hd.html
with max gain of 0.55% with the same filter. The best filter apparently
achieves the best trade-off between pass band ripple and stop band
attenuation.

Change-Id: I919e28ae245c0493147fa0864f8c9d048a9dd530

The commit adds a new set of loop filter for macroblock edge filtering.
The new loop filter has a mask to detect so-called "flat" regions. The
detection checks 5 pixels of each side of an edge. If the all pixels
have value with +/-1 from the edge pixel on the same side, the region
is treated as a "flat" region. For such case, a 7 tap filter is used
to change 3 pixel values on each side. The 7 taps are:
               [1, 1, 1, 2, 1, 1, 1]/8
The furthest away pixels used as input are +/-5 away from edge. For
non-flat region, we fall back to old filtering. It should be noted
here that the thresholds and filter taps may require more optimization
for best possible results.

Tests on a set of hd clips showed consistent gains:
http://www.corp.google.com/~yaowu/no_crawl/mblpf_hd.html
(avg psnr: .83% glb psnr: .77% ssim: .82%)

Tests on derf set also showed consistent gains:
http://www.corp.google.com/~yaowu/no_crawl/mblpf_derf.html
(avg psnr: .24% glb psnr: .22% ssim: .48%)

Change-Id: I0855b1ff48e79e1175c20b81967137e18b2af352

This commit removed the macro CONFIG_MULCONTEXT, which was used to
indicate the experiment code for using separate context for altref
and normal frames. This commit made the change fully merged in.

Change-Id: I525f927f68e2365d37b340ef23b836a136a4f70b

This commit removed the macro CONFIG_I8X8, which was used to indicate
the 8x8 intra prediction experiment, made the change fully merged in.

Change-Id: Iafa4443781ce6e83f5591c12ba615a0e92ce0ea0

This patch introduces the concept of dual inter16x16 prediction. A
16x16 inter-predicted macroblock can use 2 references instead of 1,
where both references use the same mvmode (new, near/est, zero). In the
case of newmv, this means that two MVs are coded instead of one. The
frame can be encoded in 3 ways: all MBs single-prediction, all MBs dual
prediction, or per-MB single/dual prediction selection ("hybrid"), in
which case a single bit is coded per-MB to indicate whether the MB uses
single or dual inter prediction.

In the future, we can (maybe?) get further gains by mixing this with
Adrian's 32x32 work, per-segment dual prediction settings, or adding
support for dual splitmv/8x8mv inter prediction.

Gain (on derf-set, CQ mode) is ~2.8% (SSIM) or ~3.6% (glb PSNR). Most
gain is at medium/high bitrates, but there's minor gains at low bitrates
also. Output was confirmed to match between encoder and decoder.

Note for optimization people: this patch introduces a 2nd version of
16x16/8x8 sixtap/bilin functions, which does an avg instead of a
store. They may want to look and make sure this is implemented to
their satisfaction so we can optimize it best in the future.

Change-ID: I59dc84b07cbb3ccf073ac0f756d03d294cb19281

Added two experimental options to the configure script:
1. newnear:
   new scheme of doing mv encoding that include a motion vector from
   last frame in nearest and near mv search
2. mulcontext:
   tracks entropy context separately for regular frames and alt ref
   frames.

Change-Id: If6e0d5d593351707b497a26eb6a763e080f77e6f

This commit tries to do UV intra mode coding adaptive to Y intra mode.
Entropy context is defined as conditional PDF of uv intra mode given
the Y mode. All constants are normalized with 256 to be fit in 8 bits.

This provides further coding efficiency beyond the quantizer adaptive
y intra mode coding. Consistent gains were observed on all clips and
all bit rates for HD all key encoding tests.

To test, configure with
--enable-experimental --enable-uvintra

Change-Id: I2d78d73f143127f063e19bd0bac3b68c418d756a

New setting added to configure script

make intra mode coding entropy distribution adaptive to baseQindex, an
encoding test on hd clips with all key frame shows universal gain on
all clips in both .2%(psnr) and (ssim).3%.

To build and test, configure with
--enable-experimental --enable-qimode

Change-Id: Iaa69241b984d4fdd8baa6d77ee78c0140f5ac00a

Patch 1 to Patch 3 is an initial implementation of 8x8 intra prediction
modes, here are with the following assumptions:
a. 8x8 has 4 prediction modes DC, H, V and TM
b. UV 4x4 block use the same mode as corresponding 8x8 area
c. i8x8 modes are enabled for key frame only for now
Patch 4:
d. removed debug code from previous patches
Patch 5:
e. added stats code to collect entropy stats and further cleaned up
Patch 6:
f. changed mode stats code to collect finer stats of modes
Patch 7:
g. normalized i8x8 modes distribution to total at 256 (8bits).
Patch 8:
h. fixed a bug in decoder and removed debug printf output.
Patch 9:
i. more cleanups to address paul's comment
Patch 10:
j. messy rebase/merges to bring the commit up to date.

Tests on HD clips encoded with all key frame showing consistent gain
on all clips and all metrics:~0.5%(psnr) and 0.6%(ssim):
http://www.corp.google.com/~yaowu/no_crawl/i8x8hd_allkey_fixedq.html

To build and test, configure with:
--enable-experimental --enable-i8x8

Change-Id: I9813fe07ae48cab5fdb5d904bca022514ad01e7f

Fixes issue #62.

Change-Id: I0567cf7897c0942666c19b3231c8c3b8e9c3e7cc

Please refer to previous commit messages for detailed info:
https://on2-git.corp.google.com/g/#change,5940
https://on2-git.corp.google.com/g/#change,6045

Change-Id: I8b16992f2f69c5a808ad40a3e32ef589cce7c59d

experimental branch build was broken from some merge artifacts, this
commit fixes those issues to enable the experimental branch to build.

Change-Id: Ic52b2d2f1d1b80abb7ecaa4c0927bcf887ac0c2a

The error-concealer is plugged in after any motion vectors have been
decoded. It tries to estimate any missing motion vectors from the
motion vectors of the previous frame. Intra blocks with missing
residual are replaced with inter blocks with estimated motion vectors.

This feature was developed in a separate sandbox
(sandbox/holmer/error-concealment).

Change-Id: I5c8917b031078d79dbafd90f6006680e84a23412

Renamed configure option "enable-psnr" to "enable-internal-stats" to
better reflect the purpose of the option and eliminate the confusion
reported in http://code.google.com/p/webm/issues/detail?id=35

Change-Id: If72df6fdb9f1e33dab1329240ba4d8911d2f1f7a

This gave a syntax error, preventing configure from completing.

Change-Id: I3df765f93c26e5bb3b2aab939d1cd01d6c57d450

Detect the number of available cores and limit the thread allocation
accordingly. On decoder side limit the number of threads to the max
number of token partition.

Core detetction works on Windows and
Posix platforms, which define _SC_NPROCESSORS_ONLN or _SC_NPROC_ONLN.

Change-Id: I76cbe37c18d3b8035e508b7a1795577674efc078

Rules are added to libs.mk to generate a vpx.pc, which is
installed as pkgconfig/vpx.pc under the target library directory.
This also requires the install path prefix be exported directly
in config.mk.

Some systems use a tool called pkg-config to query information
about intalled libraries or other resources, based on database
files provided by the packages themselves at install time.

Providing such a file for libvpx simplifies integration with
other build systems, and provides an easy avenue for developers
to test against their own builds of the library.

Change-Id: I4e32a8fbb53fc331aa95eb207c63dd70a76d18ed

The configure script exports the major/minor/patch version
numbers, but didn't make the full version string available
to Makefile recipes and rules, the way it is available to
C code from vpx_version.h.

Change-Id: Ic6a9d4c574a6ea66a50c928f4eedeb91d7668eb5

this has been broken since the initial release

Change-Id: If0d4deb2de9f7d0c4c05641e2bbf9cc1bf11e171

hasn't been kept up to date. remove it to avoid confusion.

Change-Id: I52ffde19b59fec5c7a381299ca2e85cb38330be7

Only suppress unused function warnings, rather than supprressing all
unused-* warnings. Unused functions can still be seen with
--enable-extra-warnings.

Change-Id: Ibca20d859dbffedd76bd082ffe0fa685c3ac198e

Adds following targets to configure script to support RVCT compilation
without operating system support (for Profiler or bare metal images).
 - armv5te-none-rvct
 - armv6-none-rvct
 - armv7-none-rvct

To strip OS specific parts from the code "os_support"-config was added
to script and CONFIG_OS_SUPPORT flag is used in the code to exclude OS
specific parts such as OS specific includes and function calls for
timers and threads etc. This was done to enable RVCT compilation for
profiling purposes or running the image on bare metal target with
Lauterbach.

Removed separate AREA directives for READONLY data in armv6 and neon
assembly files to fix the RVCT compilation. Otherwise
"ldr <reg>, =label" syntax would have been needed to prevent linker
errors. This syntax is not supported by older gnu assemblers.

Change-Id: I14f4c68529e8c27397502fbc3010a54e505ddb43

Add --extra-cflags as config parameter for user defined extra CFLAGS.
Add -g to asflags when debug enabled for arm targets.

Change-Id: Ibdde7cfdda6736c1c1db45e6466bd08504a51f15

Prior to this change, VP8 min quantizer is 4, which caps the
highest quality around 51DB. This experimental change extends
the min quantizer to 1, removes the cap and allows the highest
quality to be around ~73DB, consistent with the fdct/idct round trip
error. To test this change, at configure time use options:

--enable-experimental --enable-extend_qrange

The following is a brief log of changes in each of the patch sets

patch set 1:
In this commit, the quantization/dequantization constants are kept
unchanged, instead scaling factor 4 is rolled into fdct/idct.
Fixed Q0 encoding tests on mobile:
  Before:    9560.567kbps Overall PSNR:50.255DB VPXSSIM:98.288
  Now:   18035.774kbps Overall PSNR:73.022DB VPXSSIM:99.991

patch set 2:
regenerated dc/ac quantizer lookup tables based on the scaling
factor rolled in the fdct/idct. Also slightly extended the range
towards the high quantizer end.

patch set 3:
slightly tweaked the quantizer tables and generated bits_per_mb
table based on Paul's suggestions.

patch set 4:
fix a typo in idct, re-calculated tables relating active max Q
to active min Q

patch set 5:
added rdmult lookup table based on Q

patch set 6:
fix rdmult scale: dct coefficient has scaled up by 4

patch set 7:
make transform coefficients to be within 16bits

patch set 8:
normalize 2nd order quantizers

patch set 9:
fix mis-spellings

patch set 10:
change the configure script and macros to allow experimental code
to be enabled at configure time with --enable-extend_qrange

patch set 11:
rebase for merge

Change-Id: Ib50641ddd44aba2a52ed890222c309faa31cc59c