This patch revamps the entropy coding of coefficients to code first
a non-zero count per coded block and correspondingly remove the EOB
token from the token set.

STATUS:
Main encode/decode code achieving encode/decode sync - done.
Forward and backward probability updates to the nzcs - done.
Rd costing updates for nzcs - done.
Note: The dynamic progrmaming apporach used in trellis quantization
is not exactly compatible with nzcs. A suboptimal approach has been
used instead where branch costs are updated to account for changes
in the nzcs.

TODO:
Training the default probs/counts for nzcs

Change-Id: I951bc1e22f47885077a7453a09b0493daa77883d

Added a variant of the one shot maxQ flag
for two pass that forces a fixed Q for the
normal inter frames. Disabled by default.
Also small adjustment to the Bits per MB
estimation.
Change-Id: I87efdfb2d094fe1340ca9ddae37470d7b278c8b8

Optimized adding diff to predictor, which gave 0.8% decoder
performance gain.

Change-Id: Ic920f0baa8cbd13a73fa77b7f9da83b58749f0f8

Removing redundant 'extern' keywords, fixing formatting and #include order,
code simplification.

Change-Id: I0e5fdc8009010f3f885f13b5d76859b9da511758

* changes:
  vpxenc: actually report mismatch on stderr.
  Make superblocks independent of macroblock code and data.

Because ctx->err is not set in that case, it will not report the error
on stderr.

Change-Id: Ifacbf5a03e676fd56522b03c0281d6c723c563ee

Split macroblock and superblock tokenization and detokenization
functions and coefficient-related data structs so that the bitstream
layout and related code of superblock coefficients looks less like it's
a hack to fit macroblocks in superblocks.

In addition, unify chroma transform size selection from luma transform
size (i.e. always use the same size, as long as it fits the predictor);
in practice, this means 32x32 and 64x64 superblocks using the 16x16 luma
transform will now use the 16x16 (instead of the 8x8) chroma transform,
and 64x64 superblocks using the 32x32 luma transform will now use the
32x32 (instead of the 16x16) chroma transform.

Lastly, add a trellis optimize function for 32x32 transform blocks.

HD gains about 0.3%, STDHD about 0.15% and derf about 0.1%. There's
a few negative points here and there that I might want to analyze
a little closer.

Change-Id: Ibad7c3ddfe1acfc52771dfc27c03e9783e054430

Change-Id: I5637d491eb6a9b7633f72e03fd9df72131eeb121

Wrote a SSE2 vp9_short_idct4x4llm to improve the decoder
performance.

Change-Id: I90b9d48c4bf37aaf47995bffe7e584e6d4a2c000

Fixed a couple of variable/function definitions, as well as header
handling to support 16K sequence coding at high bit-rates.

The width and height are each specified by two bytes in the header.
Use an extra byte to explicitly indicate the scaling factors in
both directions, each ranging from 0 to 15.

Tested coding up to 16400x16400 dimension.

Change-Id: Ibc2225c6036620270f2c0cf5172d1760aaec10ec

* changes:
  Add unit test for x4 multi-SAD functions
  Add VP9 1 block SAD functions to unit test
  Merge master branch into experimental

Update the function prototypes to match between VP9 and VP8.

Change-Id: If58965073989e87df3b62b67a030ec6ce23ca04f

Change-Id: I06b5ba5c457944cfa4cd9f53c3bd8cda132439c2

Change-Id: Iab0176f058045181821ded95ff1cf423af1625f9

Removing redundant 'extern' keyword, lowercase variable names.

Change-Id: I608e8d8579aba8981f5fac3493f77b4481b13808

Change-Id: I7977694223521404fc69f29ae2cff03e36e87299

Picks up some build system changes, compiler warning fixes, etc.

Change-Id: I2712f99e653502818a101a72696ad54018152d4e

to be a fixed value of 15.

Test results:
cif:  .124%, .068%, .081%
std-hd: 2.809%, 3.174%, 2.705%

Change-Id: I380c8152c973506094da15eab59e3aa22b75a983

Simplified idct32x32 calculation when there are only 10 or less
non-zero coefficients in 32x32 block. This helps the decoder
performance.

Change-Id: If7f8893d27b64a9892b4b2621a37fdf4ac0c2a6d

* changes:
  Ignoring test video sequences in the source tree.
  Code cleanup.

gf_group_bits is int64_t remove casts to int.

Change-Id: I3b4225905041fac9af9fdfcbcb6f1c357ea4b593

Adding /*.ivf and /*.ivf.md5 filename patterns to .gitignore.

Change-Id: I9be9c99023e6b59bcc9cfbb6c9d6cdc8e500fc4f

Lower case variable names, converting while loops to for loops.

Change-Id: Ic3b973391eef7472a99d18d02fe79cfef5e04e62

Provided a wrapper and removed duplicate code.

Change-Id: Iaef842226ec348422e459202793b001d0983ea30

Change-Id: Ie89bd00d58e30bf4094cb748a282f1dfa81a31d8

Change-Id: Id786be31da3c91d95d2955aa569ecdc6e66650df

The ABOVESPREFMV experiment uses four pixels to the left of the
current block, which don't exist for the left-most column.

Change-Id: I4cf0b42ae8f54c0b3e7b1ed8755704b74fafc39c