This commit allows encoder to compare the SAD cost associated with
the best motion vector predictor, per frame. If one reference frame
has this cost more than 4 times of the best SAD cost given by other
reference frames, skip NEARESTMV, NEARMV, ZEROMV mode check of this
reference frame.

This setting is turned on in speed 2 and above. Compression quality
change in speed 2:
derf  -0.014%
yt    -0.097%
hd    -0.023%
stdhd  0.046%

It reduces the speed 2 runtime of test sequences:
pedestrian_area_1080p 4000 kbps 310763 ms -> 303595 ms
bluesky_1080p 6000 kbps         259852 ms -> 251920 ms

Change-Id: I7f59cf79503d51836d61d56d50dc5bdf0e502e22

This commit further optimizes SSE2 operations in the second 1-D
inverse 16x16 DCT, with (<10) non-zero coefficients. The average
runtime of this module goes down from 779 cycles -> 725 cycles.

Change-Id: Iac31b123640d9b1e8f906e770702936b71f0ba7f

This commit is the first patch optimizing SSE2 implementation of inverse
16x16 DCT with <10 non-zero coefficients. It focused on the first 1-D (row)
transformation. It exploits the fact that only top-left 4x4 block contains
non-zero coefficients, in a 2-D inverse 16x16 DCT with <10 coeffients.

The average runtime of idct16x16_10 unit is reduced from
883 cycles -> 779 cycles (12% faster).

For pedestrian_area_1080p 300 frames at 4000 kbps, the speed 2 runtime goes
down from 310651 ms  -> 305910 ms. The decoding speed goes up from
80.37 fps -> 80.87 fps.

Change-Id: Ic6f3ac5a637a76c07ba73ddaafe318a699fea645

For systems without __builtin_clz() or _BitScanReverse(), taken from libwep

Change-Id: Iead257efc1772c466c79e1dc0356ed571d38d43e

More intra optimizations will be added.

Change-Id: I33ae8d93f6002bf7b64cc2669602d9e6bfa5a6e8

Optimizing the variance functions: vp9_variance16x16, vp9_variance32x32,
vp9_variance64x64, vp9_variance32x16, vp9_variance64x32,
vp9_mse16x16 by migrating to AVX2
some of the functions were optimized by processing 32 elements instead of 16.
some of the functions were optimized by processing 2 loop strides of 16
elements in a single 256 bit register
This optimization gives between 2.4% - 2.7% user level performance gain
and 42% function level gain.

Change-Id: I265ae08a2b0196057a224a86450153ef3aebd85d

Change-Id: I44eb44eb3f36c05d916ef140ef42cc84f72f99ec

Change-Id: I28e9cf9347acd7279df3b841863a248479633265

Some cleanups on frames_to_key, frames_since_key.
Also removes the unused fixed_q parameters in vp9.

Change-Id: If8743a32c71de30a8d17136477b53d607a7acda8

The previous implementation stops motion vector prediction test when
the zero motion vector appears for the second time. This commit fixes
it by simply skipping the second time check on zero mv and continuing
on to next mv candidate.

It slightly improves stdhd in speed 2 by 0.06% on average. Most static
sequences are not affected. A few hard ones, like jet, ped, and riverbed
were improved by 0.1 - 0.2%.

Change-Id: Ia8d4e2ffb7136669e8ad1fb24ea6e8fdd6b9a3c1

This resolves a merge error.

Change-Id: Ifb83acc0a08e80c82f7624f9c86f79d3a86cc871

The code can be removed because mvp_full will be overridden after that.

Change-Id: I89559b1b6914c86bcd02b7359d37241948ac11d3

Change-Id: I9631b35810c232c134f39dc0edadb1b3860a45ae

Change-Id: I064ba32d5358bfbf080a4300fc1793b345080006

Change-Id: Ic5bf5682ccdb8d2fbad6bba0d7db19a4f47b62a1

rewind() does not work on pipes.

https://code.google.com/p/webm/issues/detail?id=678

Change-Id: I057f1e25c3f5662012d6e33ff4c97c88f50df357

Change-Id: I44a89b822a436299b9dd4ff26ad2e35767c29c58

The file was removed by 9152f485 after
the solution files were changed.

Change-Id: I868c56fd609f45fb3e21afd085b9e6c268aac038