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

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

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

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

Change-Id: Iaf698ef7ee3aef9edd59015e1ae065dd359b17d9

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

Change-Id: Id4138293efeac4503b2e01ce7a6c150a5abeef77

Counts are separate from frame context. We have several frame contexts but
need only one copy of all counts.

Change-Id: I5279b0321cb450bbea7049adaa9275306a7cef7d

Several consecutive for loops executed over the same
index range, so I rolled them into one.

Change-Id: I5cfcc8c38c738478965768409cca9d09adf224e1

many structures use bw and bh and they have different meanings.   This cl attempts
to start this clean up and remove unneccessary 2 step look up log and then
shift operations...

also removed partition type multiple operation code in bitstream.c.

Change-Id: I7e03e552bdfc0939738e430862e3073d30fdd5db

Moving common encoder/decoder code to update_tx_counts. Also renaming
vp9_get_pred_probs_tx_size to get_tx_probs2 and adding get_tx_probs to
call vp9_get_pred_context_tx_size inside read_selected_tx_size only once
(twice before).

Change-Id: Ia50247f3893de88ef8e9041b0d44be44a40aaa4d

This cl fixes issues rbultje brought up. that I somehow neglected when I
submitted yaowu's patch.

Change-Id: I07ad18796317822510b96e951c88d29f194a3c2e

At speed 2, due to the threshold scheme used, it is possible the rate
and distortion assigned with INT_MAX value. The patch added checking
to prevent the INT_MAX value is used in further calculation of RD
scores. The patch also changed the assertion in rd_use_partition() to
be mirror similar assertion in rd_pick_partition().

Change-Id: Idb52c543cc1e10abdf6e6a5d6e9cb535a42214dc

Adding loopfilter struct with fields from MACROBLOCKD and VP9Common.
Eventually it will be moved to vp9_loopfilter.h for better code structure.

Change-Id: Iaf5fb71c33719cdfa1b991f671caf071be9ea035

Change-Id: Ia4e83913251c1cdc7aa2abd64bf01ecb1a962119

Moving TX_MODE enum to vp9_enums.h. Renaming txfm_mode variables to
tx_mode.

Change-Id: I459d1af6dd928ce7fccdf8ce30b6f1ca057bef92

Functions: vp9_get_pred_context_switchable_interp,
           vp9_get_pred_context_intra_inter,
           vp9_get_pred_context_single_ref_p1,
           vp9_get_pred_context_single_ref_p2.

Change-Id: I3d6fb8aee23c9062270768e1e6da416dd9bb8f96

We would skip the rectangular blocks for sub8x8 partitions because
we would conclude that PARTITION_NONE was better than PARTITION_SPLIT,
however, that conclusion was made before we actually really tested
PARTITION_SPLIT.

Change-Id: I8fa91e59894badc1d8cee3ba8a49e40ae4c4a489

This prevents a duplicate memcpy of a 128-byte struct every time
set_scale_factors() is called (which is a lot), thus leading to a
decrease from 3.7 MB to 1.85 MB of struct copying per 64x64 block
RD/partition loop.

Overall, this decreases encoding time of the first 50 frames of bus
@ 1500kbps (speed 0) from 1min5.9 to 1min4.9, i.e. about a 1.5%
overall speedup. We can likely get more gains by removing the copy
of the other struct (and replacing it with an indexing) as well.

Change-Id: I3dceb7e79f71e6fe911b11cc994cf89a869dde7a

The same information already exists in union b_mode_info.

Change-Id: Iac5086b99a3c3cc270380138062bb693e58f9e6d

About 15% faster for bus (speed 0) first 50 frames @ 1500kbps, which
goes from 1min36 to 1min24. Results become slightly better (+0.2% on
derf/yt, +0.4% on hd), probably because of a bugfix for skipmode in
super_block_yrd(). Overall speed change (on derfraw300) is roughly
-13%. This can probably be improved further by caching best_yrd
between partition searches. Also, we might be able to get more
speedups by always doing PARTITION_NONE before PARTITIONS_SPLIT, not
just at the sb8x8 level.

Change-Id: I83736949ebd5b4a3b400ee688d7661913fefc98b

Current partition checking starts from small sizes, and then goes up
to large sizes. This experiment uses the small partitions' motion
estimation result, which is already available, to speed up the
large partition's motion estimation. We can decide to skip some
patition checkings if they are unlikely choices. We could use the
motion vector(MV) result as current partition's prediction MV, limit
the search range and reference frame.

Current result at speed 1:
psnr loss: 1.19% for stdhd, 0.287% for derf.
speed gain: 14% for sunflower(hd), 11% for akiyo.

Further improvement will be done later.

Change-Id: I5abfd070e9cace2e91e2a0247d1325df313887ab

Removing VP9_COMMON* argument and adding struct tx_probs* instead of
MACROBLOCKD*.

Change-Id: Idf61074631a90ec51eac22c8dcd977f44ac0757c

Removing tile_rows and tile_columns from VP9Common, removing redundant
constants MIN_TILE_WIDTH and MAX_TILE_WIDTH, changing signature of
vp9_get_tile_n_bits.

Change-Id: I8ff3104a38179b2c6900df965c144c1d6f602267

Making implementation of vp9_set_pred_flag_{seg_id, mbskip} consistent
with vp9_get_segment_id without using confusing sub(a, b) macro. Passing
mi_row and mi_col to functions explicitly instead of replying on
mb_to_right_edge and mb_to_bottom_edge.

Change-Id: I54c1087dd2ba9036f8ba7eb165b073e807d00435

This speed feature allows the encoder to largely remove the spatial
dependency between blocks inside a 64x64 superblock, thereby removing
the need to repeatedly encode superblocks per partition type in the
rate-distortion optimization loop.

A major challenge lies in the intra modes tested in the rate-distortion
optimization loop. The subsequent blocks do not have access to the
reconstructed boundary pixels without the intermediate coding steps.
This was resolved by using the original pixels for intra prediction
in the rd loop, followed by an appropriately designed distortion
modeling on the quantization parameters. Experiments also suggested
that the performance impact is more discernible at lower bit-rate/psnr
settings. Hence a quantizer dependent threshold is applied to deactivate
skip of block coding.

For bus_cif at 2000 kbps,
speed 0: runtime 269854ms -> 237774ms (12% speed-up) at 0.05dB
         performance loss.

speed 1: runtime 65312ms  -> 61536ms, (7...

frames_since_golden / frames_till_alt_ref_frame are unused.

Change-Id: I348e7689d4d75412cf4de7703d885be942e4a26b

Change-Id: Id9b6ceeddca3f9b34bfada5c499b1e7a2f42c30b

Also removing unused declarations from vp9_entropymode.h file.

Change-Id: Ib9c5826db3584a32f6bb3297a76c522b99d83402

Removing redundant function arguments and curly braces.

Change-Id: I46e02561f33fe02e84a3b19756f03b9504bd6a1b

Adding segmentation struct to vp9_seg_common.h. Struct members are from
macroblockd and VP9Common structs. Moving segmentation related constants
and enums to vp9_seg_common.h.

Change-Id: I23fabc33f11a359249f5f80d161daf569d02ec03

Change-Id: I0543e72fa092eef3976b65e16bb597197c364873

Change-Id: I5dea4570cb05df27a522abf6e7b695998654284a

Change-Id: Ie0cb732fdcb98616a422c4463bff80642248d136

Removes SEG_ID
Removes MBSKIP
Removes SWITCHABLE_INTERP
Removes INTRA_INTER
Removes COMP_INTER_INTER
Removes COMP_REF_P
Removes SINGLE_REF_P1
Removes SINGLE_REF_P2
Removes TX_SIZE

Change-Id: Ie4520ae1f65c8cac312432c0616cc80dea5bf34b

The resulting reconstruction is never used, thus it just wastes CPU
cycles. Reduces encode time of first 50 frames of bus (speed 0) @
1500kbps from 2min2.0 to 2min1.2, i.e. a 0.65% overall speedup.

Change-Id: I74755ca3aadc21e2be220f486259060bd4088c45

Overall, on all test sets, this gains about +0.2% on all metrics.
City is a clip where this really hurts (-1.0% on all metrics), I'm
not quite sure why yet. Maybe interesting to look into in the future.

Change-Id: I6f0eecb20e72f0194633270d30bf00d76d9eae78

Eliminating usage of mb-units, switching to mi-units. Adding
ALIGN_POWER_OF_TWO macro.

Change-Id: I2491c969f713207c062011878b57e4e531818607

Skips mode searches for intra and compound inter modes depending
on the best mode so far and the reference frames. The various
heuristics to be used are selected by bits from a flag. The
previous direction based intra mode search pruning is also absorbed
in this framework.

Specifically the flags and their impact are:

1) FLAG_SKIP_INTRA_BESTINTER (skip intra mode search for oblique
directional modes and TM_PRED if the best so far is
an inter mode)
derfraw300: -0.15%, 10% speedup

2) FLAG_SKIP_INTRA_DIRMISMATCH (skip D27, D63, D117 and D153
mode search if the best so far is not one of the closest
hor/vert/diagonal directions.
derfraw300: -0.05%, about 9% speedup

3) FLAG_SKIP_COMP_BESTINTRA (skip compound prediction mode
search if the best so far is an intra mode)
derfraw300: -0.06%, about 7-8% speedup

4) FLAG_SKIP_COMP_REFMISMATCH (skip compound prediction search
if the best single ref inter mode does not have the same ref
as one of the two references being tested in the compound mode)
derfraw300: -0.56%, about 10% speedup

Change-Id: I1a736cd29b36325489e7af9f32698d6394b2c495

Removing set_refs, adding set_ref function.

Change-Id: I5635c478b106ae4e57d317f1c83d929644307e63

Change-Id: I32276552b3ea6dc1dce8e298be114cfe1019b31c