Preliminary patch on a new 4x4 intra mode B_CONTEXT_PRED where the
dominant direction from the context is used to encode. Various decoder
changes are needed to support decoding of B_CONTEXT_PRED in conjunction
with hybrid transforms since the scan order and tokenization depends on
the actual direction of prediction obtained from the context. Currently
the traditional directional modes are used in conjunction with the
B_CONTEXT_PRED, which also seems to provide the best results.

The gains are small - in the 0.1% range.

Change-Id: I5a7ea80b5218f42a9c0dfb42d3f79a68c7f0cdc2

Missing eobs agrument in vp9_dequant_idct_add_16x16_c

Change-Id: I826b1afa0a4ee6398f7373325aa0c75e6a866937

The altref frame is packed along with the next P frame. So that
outside of the codec there are now only two types of frames P and I.
Also, now it is one frame in and one frame out with respect to the
codec. Apart from that, all the frames are length encoded with the
length of each frame appended to the frame itself. There are
two categories of frames and each of them will look as follows:

  - Packed frames (an altref along with the succeeding p frame)
    - altref_frame_data | altref_lenngth | frame_data | length
  - Unpacked frames (all frames other than the above)
    - frame_data | length

Change-Id: If1eabf5c473f7d46b3f2d026bd30c803588c5330

cleanup

Change-Id: I565eee40d900e0441ad211b65ac829fc5b93d94a

Also split superblock handling code out of decode_macroblock() into
a new function decode_superblock(), for easier readability.

Derf +0.05%, HD +0.2%, STDHD +0.1%. We can likely get further gains
by allowing to select mb_skip_coeff for a subset of the complete SB
or something along those lines, because although this change allows
coding smaller transforms for bigger predictors, it increases the
overhead of coding EOBs to skip the parts where the residual is
near-zero, and thus the overall gain is not as high as we'd expect.

Change-Id: I552ce1286487267f504e3090b683e15515791efa

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: Ib39ad47a7d188f3b45416937b7eeb28c3e79b74c

In the variance calculations the difference is summed and later squared.
When the sum exceeds sqrt(2^31) the value is treated as a negative when
it is shifted which gives incorrect results.

To fix this we force the multiplication to be unsigned.

The alternative fix is to shift sum down by 4 before multiplying.
However that will reduce precision.

For 16x16 blocks the maximum sum is 65280 and sqrt(2^31) is 46340 (and
change).

This change is based on:
16982342 Missed some variance casts
fea3556e Fix variance overflow

Change-Id: I2c61856cca9db54b9b81de83b4505ea81a050a0f

so they are consistent with actual definitions of the functions

Change-Id: Ie4b4e81b3da3e288fc2edbbd2b393a5c54d2556b

Change-Id: Iedaa108ddb65f54d768424f9c47ad4d069b656fd

s/([vV][pP])8/$19/
additionally dct.h was removed; declare the _c functions that are used
in the tests. the TODO for conversion to parameterized tests still
remains.

Change-Id: I73db9425a57075bbb78a92693ba6b320578981cd

Change-Id: I44b3ad780cef6f448fa17ff8e28fea87ef9cd518

Converted vp9_short_fdct16x16_c and vp9_short_idct16x16_c to
integer versions.

Change-Id: Ie3ec985a890ac0f4f4f5818e6f0122e00c8af69f

Change-Id: Ibfac7e000509d2017eac9a108060e534a19fec33

there are still a couple type of warning left, which are related to
double constants assigned to float type. As those would be addressed
by the conversion of transforms into integer version. This commit
has left those un-dealt with.

Change-Id: I48fd9b489c0c27ad6b543f4177423419f929f2bb

calculate the txfm_cache difference first as both values may be
INT64_MAX with the intent that they cancel each other out.

Change-Id: I214d072458e1b24f60289974e6302af1aff7b66c

Removed invoke search from encoder

Change-Id: I3d809b795abe6df0e71366edfe94026aaede14fb

rd_pick_intra4x4mby_modes / rd_pick_intra8x8mby_modes would both use the
input value of 'rate_y' in the return calculation. In many places this
value is uninitialized. Remove the unneeded sum.

Change-Id: Icbd3df685303000301e69291c0ebc06f74bd548d

use unsigned ints to extended filter values in
vp9_mbloop_filter_horizontal_edge_c_sse2

Change-Id: I55ec3ac2bcb9baf55626b0384d151b07fc8e087d

The block sizes for decoding tokens are up to 16x16, which means
eobs is within [0, 256]. Using (signed) char is not enough. Changed
eobs data type to unsigned short to fix the problem.

Change-Id: I88a7d3098e1f1604c336d6adb88ffec971fb03a6

Change-Id: Ia601e96fcb4fc547884b6ab894f9f2ad22a98078

Change-Id: I7cd21b9f1e69f4e0b3338bfe27b3c67e4b47de58

Update vpx_scale from current code in master, run style transform, fix
lint warnings.

Change-Id: I47eadeb5b6881d448ea3728537f9b8a5b5aac78e

Change-Id: Ic084c475844b24092a433ab88138cf58af3abbe4