Substantial reworking of the speed vs quality trade offs for
speed 1 and 2.

In this patch I am attempting to freeze the "quality" meaning of
speeds 1 and 2 relative to speed 0 so that in future we can
better evaluate progress.

I am targeting :
Speed 1 quality ~-5% vs speed 0.
Speed 2 quality ~-10% vs speed 0

It is inevitable that quality will still fluctuate a little as we adjust
settings and add new features, but we will attempt to keep as
close as possible to these values. Above speed 2 things will remain
a bit more fluid for now.

In this patch speed 1 is approximately 4-5x as fast as speed 0. This
is similar to before but the quality hit is a lot less. Likewise speed 2
is approximately 2x as fast as speed 1 but is similar in quality to the
previous speed 1 configuration.

Also slight change to behavior of FLAG_EARLY_TERMINATE to insure
all reference frames get at least one rd test. Important for very low
variance regions.

WIP :- Added a new speed level with old speed 4 becoming speed 5.
Speed 3 and 4 tradeoffs still WIP

Change-Id: Ic7a38dd7b5b63ab1501f9352411972f480ac6264

This commit causes use last partition to consider whether a 64x64 has
motion that might make a new partitioning worth while.

Change-Id: I3a57bedef4f3cd961fadbfa96651c206fa36da4a

Adding appropriate test vector vp90-2-06-bilinear.webm.

Change-Id: Ia3bbf57318e0cc61a1b724fe751e3f9c7e11b337

Remove mode_check_freq and mode_test_hit_counts from VP9_COMP.

Change-Id: Iabfd9f841444cd9bf19ac761a9795f140082ce0b

Change-Id: Icc6a76a5be77f3e19918155bab3998e0aa32ccf5

Change-Id: I6c4058aebe834e1a12b7a3fb10484b9ebe60b349

Change-Id: I84209d382ca5dfc537ee533cd792d8caa0e25cee

Also renaming mb_row -> mi_row, mb_col -> mi_col arguments and calculate
mb_rows/mb_cols values from mi_rows/mi_cols.

Change-Id: I6919a279f560648e23bc9a12f507d17c21ffd5d7

Make encoder skip rectangular partition check in speed 1 and above,
when early termination was triggered in partition split.
Thanks Guillaume (gmartres@) for catching this issue.

This change makes bus_cif at 2000kbps speed 1 runtime goes down from
25612ms to 23438ms (about 9% speed-up), at the expense of -0.235%
performance down.

Change-Id: I98613fad081a261d30d5fa206f934ca70601c180

The code now takes into account temporal and spatial
information to determine the partition size range, but the
frequency counts have been removed.

The net effect is similar in quality but about 10% faster.

Change-Id: I39a513fb79cec9177b73b2a7218f0da70963ae95

This patch deletes the variance based speed three partitioning.
Speed 3 now uses the same partitioning method as speed 2
but with some stricter conditions.

The speed and quality are now somewhere between speeds 2 and 4
whereas before it was worse in both than speed 4.

Change-Id: Ia142e7007299d79db3ceee6ca8670540db6f7a41

Change-Id: Ia455c1900d84a3221e3681e31e15ca86bd03f89d

Making name consistent with vp9_short_idct8x8 and vp9_short_idct8x8_1.

Change-Id: I99e0be040ec893f9571dcf090e18f98dc58339f5

Change-Id: I6be72c8b048d1ccc7ef43764cf84c32360098970

Some small changes to the quantizer mapping functions.
Also includes some cleanups.

Change-Id: I9dea29b24015f6e6697012a0e4d8983049d8e5c7
Results:
derfraw300: +0.106%
stdhdraw250: +0.139%

Making function name consistent with vp9_short_idct16x16 and
vp9_short_idct16x16_1.

Change-Id: I70e54be9e6b9a1dddab0de470686591e96d05517

Don't divide RDMULT and RDDIV by 100 when RDMULT > 1000. This was
probably done to avoid overflow when the rd cost was stored in a 32 bits
integer but this is not the case anymore. This change will make it easier
to support multiple quantizers per frame.

derf compression gain at speed 0: 0.037%

Change-Id: Ibeeb9b7cfa1a132a7af41bc90fc07a3bba0857f6

Change-Id: I60dee58a4fd24d3c4f3c101a49d30e217309f43a

Change-Id: I9795d0937bc07793c13d067281995e0750f694d9

Moving all code from that file to vp9_variace_c.c in the encoder.

Change-Id: Ic803d5b4c78d5191e4d25541b3df97337878fc3e

Change-Id: Ife0dd29fb4ad65c7e12ac5f1db8cea4ed81de488

Renaming txfm_stepdown_count to tx_stepdown_count and max_txfm_size to
max_tx_size.

Change-Id: Ifc173e22c78240e561a57c4c741b64b1b8fc6fef

Using best_mv[2] array instead of two separate variables.

Change-Id: Iefa0a41f5c42c42f2c66cef26750da68405f0f25

Change-Id: Ie51306689c0dc527a8aa12d3984389dd8f360dea

This fix a bug introduced by ac6093d1

Change-Id: I0700a4daf7a6a2471074f81a4596352287fb2ac9

Both first pass and mbgraph search use block size 16x16 for motion
estimation. This commit put a limit of motion vector range. The
effective range allows the entire 16x16 with required subpel
interpolation input to be completely outside image border, but
not any further away from image border.

Change-Id: Id70a5ed08be49e70959f064859d72adc7d775d08

Updating fractional_mv_step_fp and fractional_mv_step_comp_fp function
types.

Change-Id: I601c4378bc39ac3ffd4e295d9cbd8e1f74829d46

Also removed obselete comment

Change-Id: Iae1664777d76383639c637ee786e0d50fc45819a

The change is to better reflect the nature of the constants.

Change-Id: Icabac6e9bceefbdb3f03f8218f88ef75943c30fb

INT64_MAX may be assigned as RDCOST when RDCSOST computation is skipped
for speed, this commit to prevent INT64_MAX from being used as real
RDCOST in transform size decision.

Change-Id: I89a945134191bbdea1f1431ade70424ac079eaac

Improves results a little.

Change-Id: I7bcac02dbb65b43a993445cf557c520197114e5c

After change of MI context storage , mi_8x8[]  pointer may be null for
a block outside of image border. The commit changes to access the data
only after validation of mi_row and mi_col.

Change-Id: I039c4eb486a228ea9d8e5f35ab9ae6717d718bf3

Mathematically the results are the same.

Change-Id: I1c5126cd3ca64e8515ca6331e0989c6f7dd651a0

39c7b01d accidently reverted the row/col initialization, which broke
mv clamps, which is dependent on the sites for valid motion vector
range. This commit fixed the issue.

Change-Id: Ibcce0226e0360b1ef483fe760b2e33f1af4bf494

This commit enables forcing all coefficients zero per transformed
block, when its rate-distortion cost is lower than regular coeff
quantization.

The overall performance improvement (including its parent patch on
calculating rd cost per transformed block) at speed 1:
derf:  0.298%
yt:    0.452%
hd:    0.741%
stdhd: 0.006%

Change-Id: I66005fe0fd7af192c3eba32e02fd6d77952accb5

Adds modeled functions to decide the qp for altref frames in constant q
mode similar to other functions in use in bitrate mode.

Also turns on the constrained quality mode (end-usage=2) option which
was turned off before. Basic testing shows the mode works in principle,
to cap bitrate to the target-bitrate specified, while allowing lower
bitrate depending on the cq-level specified. The mode will need to be
improved over time.

Results for constant quality vs bitrate control mode:
derfraw300/fullderfraw: +3.0% at constant quality over bitrate control.
fullstdhdraw: +4.341%
stdhdraw250: +5.361%

Change-Id: If5027c9ec66c8e88d33e47062c6cb84a07b1cda9

This commit makes the rate-distortion optimization loop evaluate
the rd costs of regular quantization and all zero coeffs, per
transformed block. It improves speed 1 compression performance:

derf: 0.245%
yt:   0.515%

For a large partition that consists multiple transformed blocks,
this allows more flexibility to selectively force a portion of
them coded as all zero coeffs, as well be continued in the next
patches.

Change-Id: I211518be4179747b57375696f017d1160cc91851

Change-Id: I584fe50f73879f6a72fada45714ef80893b6d549

Converting vp9_mv_bit_cost, mv_err_cost, and mvsad_err_cost
functions for now.

Change-Id: I60e3cc20daef773c2adf9a18e30bc85b1c2eb211

Change-Id: Ie47f53e76bc9530475c8c6d24e9b7a5a0189de56