The function name rd_pick_intra4x4mby_modes is confusing, so
I changed it to rd_pick_intra_sub_8x8_y_modes to better
reflect what the function does. Also added const qualifiers
to some of the input parameters and removed camel-case.

Change-Id: I23d53d4c7af5d79ed8a471acd59a09bbb47add39

This commit removes redundant arguments passing in the function of
rd_pick_reference_frame. This resolves the clang warnings about
potential use of uninitialized values.

Change-Id: Ic68f949a9f8fcd0a583786b0c75321104ea44739

Inlining VP9_NMV_UPDATE_PROB constant, consistent local variable names.

Change-Id: I01692501982568fa535882d6b320e3c692f88abb

Passing mi_row and mi_col parameters to functions explicitly. Removing
unused xd argument from scale_mv function.

Change-Id: Icb4c495ec72d26fb066c14470d3ae0b741fbf18a

Using different variable names "allow_hp" and "use_hp" instead of "usehp".

Change-Id: I0cd5996ddeb46bd754473b680a993c0aaf8eb879

Refactor the frame buffer referencing in choose_partition and make
it consistent with other places. This means to prevent potential
issues when we extend reference frame buffer.

Change-Id: I5ff33ed5f671e1f4cc7049622212769a9b4578d9

Using inter-mode counts instead of inter-mode-tree branch counts inside
FRAME_COUNTS structure.

Change-Id: I60dde13af37d06146d7d15543311c1b5044e9e04

Removed unnecessary code lines, replaced switch with an if,
fixed spelling errors and formatting.

Change-Id: Ie48aa4604aa0ed48362ca359d792fb21b2ec1dc6

Change-Id: Ica23b66f6664e5a5b168499584f0afffbc54794f

The tokenize_b function is only called when output flag is on. Hence
removing the conditional branch on it therein.

Change-Id: Ib709f47f23f39ca05a695faf86fa3377f11f2dd0

This commit optimizes the tokenization and detokenization operational
flow for speed-up. It makes the coding process about 0.3% faster at
speed 0.

Change-Id: I28008df7482874e4b5f237f2d418ff82a249dd56

This commit makes the encoder skip the redundant tokenization process
in the rate-distortion optimization search loop, while updating the
entropy contexts accordingly. It makes the speed 0 encoding process
about 0.5% faster at no performance change.

Change-Id: I34a4155a0b5332afeb45c93a51c7f35a294d685c

This commit provides special handle on 16x16 inverse 2D-DCT, where
only DC coefficient is quantized to be non-zero value.

Change-Id: I7bf71be7fa13384fab453dc8742b5b50e77a277c

Change-Id: I2a6a646570e2af66315e7c658d00d99f80c4b127

Fixes a warning on MSVS 2012 where the alignment of vp9_default_iscan_8x8
didn't match between its declaration and definition.

Change-Id: I1466a15635f4b22594d705d570b7e399bfb6cf21

Change-Id: I10bf06e3a3d5271221ae6a42a36074d01d493039

Change-Id: I6aa4191935aa93461a07c41b59fdae1eb5f5f107

Change-Id: I5a3e83102784cabb918a5404405fcab99c5bb9b6

This allows us to increment the position at the band-level only as
we go from one band to the next; more importantly, that allows us to
use an add instead of multiply instruction, and omit the instruction
altogether if the band doesn't change from one coef to the next, thus
being slightly faster (probably more noticeable on systems where a
multiply is expensive, like arm).

Change-Id: I4343fe35b9f9a47fa00b217bdcbf5f91ff96c381

This commit brought back the shortcut implementation of 8x8/16x16
inverse 2D-DCT. When the eob <= 10, it skips the inverse transform
operations on row 4:7/4:15 in the first round. For bus_cif at 1000
kbps, this provides about 2% speed-up at speed 0.

Change-Id: I453e2d72956467d75be4ad8c04b4482ab889d572

Renaming:
  read_intra_mode_info  -> read_intra_frame_mode_info
  read_inter_mode_info  -> read_inter_frame_mode_info
  read_intra_block_part -> read_intra_block_mode_info
  read_inter_block_part -> read_inter_block_mode_info
  read_ref_frame        -> read_ref_frames
  read_reference_frame  -> read_is_inter_block

Using num_4x4_blocks_{wide, high}_lookup instead of bit shifts.

Change-Id: I83c81573b4ef6f53f2f8d24683895014bebfba61

This commit enables a special handle for the 8x8 inverse 2D-DCT,
where only DC coefficient is quantized to be non-zero. For bus_cif
at 2000 kbps, it provides about 1% speed-up at speed 0.

Change-Id: I2523222359eec26b144cf8fd4c63a4ad63b1b011

Change-Id: I748dee8938dfb19f417f24eed005f3d216f83a82

Change-Id: Ie48035ff4f93c41f8a9b3023e6444fd10432d8fb

Speed feature experiment to set an upper and lower
partition size limit based on what has been seen
in spatial neighbors.

This seems to gives quite reasonable speed gains in local
(10-15%) and when used with speed 0 the losses are small
(0.25% derf, 0.35% stdhd). However, for now I am only
enabling it on speed 1 as there may be clashes with the existing
temporal partition selection in speed 2.

Using a tighter min / max around the range derived from the
neighbors increases speed further but at the cost of a
bigger quality loss. However,  I think this spatial method could
be combined with data from either the last frame or a variance
method (or both) to refine the range of minimum and maximum
partition size. I.e. consider the min and max from spatial and
temporal neighbors and the variance recommendation.

Change-Id: I1b96bf8b84368d6aad0c7aa600fe141b4f07435f

Used 3 * standard_deviation in internal threshold calculation
instead of fit curve. This actually approached the algorithm
better.
For comparison, similar tests were done:
The overall psnr loss is less than before.
1. derf set:
when static-thresh = 1, psnr loss is 0.329%;
when static-thresh = 500, psnr loss is 0.970%;
2. stdhd set:
when static-thresh = 1, psnr loss is 0.922%;
when static-thresh = 500, psnr loss is 1.307%;

Similar speedup is achieved. For example,
clip            bitrate  static-thresh psnr    time
akiyo(cif)       500        0          48.952  5.077s(50f)
akiyo            500        500        48.866  4.169s(50f)

parkjoy(1080p)   4000       0          30.388  78.20s(30f)
parkjoy          4000       500        30.367  70.85s(30f)

sunflower(1080p) 4000       0          44.402  74.55s(30f)
sunflower        4000       500        44.414  68.69s(30f)

Change-Id: Ic78833642ce1911dbbd1cb6c899a2d7e2dfcc1f3

Now read_inter_mode_info calls read_intra_block_part (renamed from
read_intra_block_modes) or read_inter_block_part (just added).

Change-Id: I541badea6b663e0ae692ec158665efb90ed20c03

This option exists in VP8, and it was rewritten in VP9 to support
skipping on different partition levels. After prediction is done,
we can check if the residuals in the partition block will be all
quantized to 0. If this is true, the skip flag is set, and only
prediction data are needed in reconstruction. Based on DCT's energy
conservation property, the skipping check can be estimated in
spatial domain.

The prediction error is calculated and compared to a threshold.
The threshold is determined by the dequant values, and also
adjusted by partition sizes. To be precise, the DC and AC parts
for Y, U, and V planes are checked to decide skipping or not.

Test showed that
1. derf set:
when static-thresh = 1, psnr loss is 0.666%;
when static-thresh = 500, psnr loss is 1.162%;
2. stdhd set:
when static-thresh = 1, psnr loss is 1.249%;
when static-thresh = 500, psnr loss is 1.668%;

For different clips, encoding speedup range is between several
percentage and 20+% when static-thresh <= 500. For example,
clip            bitrate  static-thresh psnr    time
akiyo(cif)       500        0          48.923  5.635s(50f)
akiyo            500        500        48.863  4.402s(50f)

parkjoy(1080p)   4000       0          30.380  77.54s(30f)
parkjoy          4000       500        30.384  69.59s(30f)

sunflower(1080p) 4000       0          44.461  85.2s(30f)
sunflower        4000       500        44.418  78.1s(30f)

Higher static-thresh values give larger speedup with larger
quality loss.

Change-Id: I857031ceb466ff314ab580ac5ec5d18542203c53

Change-Id: I0625d8ffddf590dfecd1bb8b8d6f57ef64b8bf18

Removing unused constants, macros, and function declarations. Using
ROUND_POWER_OF_TWO macro, vp9_zero, vp9_copy where possible. Moving
#include from *.h to *.c. Merging for loops for motion vectors.

Change-Id: Ic3bf841764a2bb177128bb3a6d7aa8f68229cd13

Change-Id: Ia6144d77ebed66e0739b62e4d673e26a95aa9550

Simplified the code that extracts and uses the motion
vectors for the 4 sub-partitions in rd_pick_partition.

Change-Id: Iaf698ef7ee3aef9edd59015e1ae065dd359b17d9

This commit makes the initialization of trellis coeff optimization
a per-plane operation, thereby eliminating the redundant steps in
encode_sby and encode_sbuv. It makes the encoder at speed 0 slightly
faster.

Change-Id: Iffe9faca6a109dafc0dd69dc7273cbdec19b17cd

Already defined in vp9_seg_common.h.

Change-Id: I5a0e3fa15966b1ebeb77ccd506b55fc231c22342

Moving code from vp9_adapt_mode_context to vp9_adapt_mode_probs.

Change-Id: I60829c30b28968cd813551ef3a206dfb98d323c9

The feature that uses small partition results as a measure to skip
mode evaluation at larger partition requires the flags to be reset.
The reset was missing in the code path that calls rd_use_partition().

Change-Id: Ia0a3a0aee1a862b6e2333d596808db7c48033d50

Add SSE2 implementation to handle the special case of inverse 2D-DCT
where only DC coefficient is non-zero.

Change-Id: I2c6a59e21e5e77b8cf39a4af5eecf4d5ade32e2f

Adding common merge_probs and merge_probs2 functions. Changing ints to
usigned ints in some places.

Change-Id: Icf088ffdea7cf5b95284a128916409bdd53506b0

Change-Id: I21ee76bcae101cc9f6ef1d867622e50b7ae565fc

They share the same functionality, so merging together.

Change-Id: I98a0386fcee052cb854f9ff90c283c1b844bcb79