Allows inter-frames to change resolution. Currently these are
almost equivalent to keyframes, as only intra prediction modes
are allowed, but without the other context resets that occur on
keyframes.

Change-Id: Icd1a2a5af0d9462cc792588427b0a1f5b12e40d3

Change-Id: Icb6e21dc0c2d9918faa33c8bf70943660df7ad88

First step in simplifying the segment mode and
segment EOB flags into a simpler segment skip
flag that implies 0,0 mv and EOB at position 0.

Change-Id: Ib750cac31a7a02dc21082580498efd9f7d8d72a5

Adds a flag to disable features that would inhibit frame parallel
decoding. This includes backward adaptation and MV sorting based
on search in ref frame buffer.

Also includes some minor clean-ups.

Change-Id: I434846717a47b7bcb244b37ea670c5cdf776f14d

Adds an error-resilient mode where frames can be continued
to be decoded even when there are errors (due to network losses)
on a prior frame. Specifically, backward updates are turned off
and probabilities of various symbols are reset to defaults at
the beginning of each frame. Further, the last frame's mvs are
not used for the mv reference list, and the sorting of the
initial list based on search on previous frames is turned off
as well.

Also adds a test where an arbitrary set of frames are skipped
from decoding to simulate errors. The test verifies (1) that if
the error frames are droppable - i.e. frame buffer updates have
been turned off - there are no mismatch errors for the remaining
frames after the error frames; and (2) if the error-frames are non
droppable, there are not only no decoding errors but the mismatch
PSNR between the decoder's version of the post-error frames and the
encoder's version is at least 20 dB.

Change-Id: Ie6e2bcd436b1e8643270356d3a930e8989ff52a5

This commit restores the quality lost when the buffer-to-buffer copy
logic was removed. Note that this is specific to the current use of
golden frames and will need rework when RTC functionality is added.

Change-Id: I7324a75acd96eafd9e0f9b8633d782e390d5dc21

Previously there were two frame coding contexts tracked, one for normal
frames and one for alt-ref frames. Generalize this by signalling the
context to use in the bitstream, rather than tieing it to the alt ref
refresh bit. Also increase the number of contexts available to 4, which
may be useful for temporal scalability.

Change-Id: I7b66daaddd55c535c20cd16713541fab182b1662

Remove lst_fb_idx, gld_fb_idx, alt_fb_idx, refresh_last_frame,
refresh_golden_frame, refresh_alt_ref_frame from common. Gold/Alt are
encode side conventions. From the decoder's perspective, we want to be
dealing with numbered references.

Updates to active_ref 2 signal mode context switches, vestigial from
refresh_alt_ref_frame. This needs some clean up to make sense with
increased numbers of reference frames, as well as reimplementing the
swapping of alt/golden which was previously done using the
buffer-to-buffer copy mechanism removed in an earlier commit.

Change-Id: I7334445158b7666f9295d2a2dd22aa03f4485f58

This is the first in a series of commits to add additional reference
frames to the codec. Each frame will be able to update any of the
available references, but copying between references is not
supported.

Change-Id: I5945b5ce6cc3582c495102b4e7eed4f08c44d5a1

This experiment gives little gains and adds relatively much code
complexity (and it hinders other experiments), so let's get rid of
it.

Change-Id: Id25e79a137a1b8a01138aa27a1fa0ba4a2df274a

Change-Id: I615651e4c7b09e576a341ad425cf80c393637833

Change-Id: If6c88752dffdb566f8d4322f135145270716fb8e

This patch removes the old pred-filter experiment and replaces it
with one that is implemented using the switchable filter framework.

If the pred-filter experiment is enabled, three interopolation
filters are tested during mode selection; the standard 8-tap
interpolation filter, a sharp 8-tap filter and a (new) 8-tap
smoothing filter.

The 6-tap filter code has been preserved for now and if the
enable-6tap experiment is enabled (in addition to the pred-filter
experiment) the original 6-tap filter replaces the new 8-tap smooth
filter in the switchable mode.

The new experiment applies the prediction filter in cases of a
fractional-pel motion vector. Future patches will apply the filter
where the mv is pel-aligned and also to intra predicted blocks.

Change-Id: I08e8cba978f2bbf3019f8413f376b8e2cd85eba4

Change-Id: I0df99742029834a85c4933652b0587cf5b6b2587

3.2% gains on std/hd, 1.0% gains on hd.

Change-Id: I481d5df23d8a4fc650a5bcba956554490b2bd200

Part of NEW_MVREF experiment.
Added update-able probabilities.

Change-Id: I5a4fcf4aaed1d0d1dac980f69d535639a3d59401

Various fixups to resolve issues when building vp9-preview under the more stringent
checks placed on the experimental branch.

Change-Id: I21749de83552e1e75c799003f849e6a0f1a35b07

This patch changes the token packing to call the bool encoder API rather
than inlining it into the token packing function, and similarly removes
a special get_signed case from the detokenizer. This allows easier
experimentation with changing the bool coder as a whole.

Change-Id: I52c3625bbe4960b68cfb873b0e39ade0c82f9e91

Add a function clip_pixel() to clip a pixel value to the [0,255] range
of allowed values, and use this where-ever appropriate (e.g. prediction,
reconstruction). Likewise, consistently use the recently added function
clip_prob(), which calculates a binary probability in the [1,255] range.
If possible, try to use get_prob() or its sister get_binary_prob() to
calculate binary probabilities, for consistency.

Since in some places, this means that binary probability calculations
are changed (we use {255,256}*count0/(total) in a range of places,
and all of these are now changed to use 256*count0+(total>>1)/total),
this changes the encoding result, so this patch warrants some extensive
testing.

Change-Id: Ibeeff8d886496839b8e0c0ace9ccc552351f7628

Some further changes and refactoring of mv
reference code and selection of center point for
searches. Mainly relates to not passing so many
different local copies of things around.

Some place holder comments.

Change-Id: I309f10ffe9a9cde7663e7eae19eb594371c8d055

Use these, instead of the 4/5-dimensional arrays, to hold statistics,
counts, accumulations and probabilities for coefficient tokens. This
commit also re-allows ENTROPY_STATS to compile.

Change-Id: If441ffac936f52a3af91d8f2922ea8a0ceabdaa5

This adds Debargha's DCT/DWT hybrid and a regular 32x32 DCT, and adds
code all over the place to wrap that in the bitstream/encoder/decoder/RD.

Some implementation notes (these probably need careful review):
- token range is extended by 1 bit, since the value range out of this
  transform is [-16384,16383].
- the coefficients coming out of the FDCT are manually scaled back by
  1 bit, or else they won't fit in int16_t (they are 17 bits). Because
  of this, the RD error scoring does not right-shift the MSE score by
  two (unlike for 4x4/8x8/16x16).
- to compensate for this loss in precision, the quantizer is halved
  also. This is currently a little hacky.
- FDCT and IDCT is double-only right now. Needs a fixed-point impl.
- There are no default probabilities for the 32x32 transform yet; I'm
  simply using the 16x16 luma ones. A future commit will add newly
  generated probabilities for all transforms.
- No ADST version. I don't think we'll add one for this level; if an
  ADST is desired, transform-size selection can scale back to 16x16
  or lower, and use an ADST at that level.

Additional notes specific to Debargha's DWT/DCT hybrid:
- coefficient scale is different for the top/left 16x16 (DCT-over-DWT)
  block than for the rest (DWT pixel differences) of the block. Therefore,
  RD error scoring isn't easily scalable between coefficient and pixel
  domain. Thus, unfortunately, we need to compute the RD distortion in
  the pixel domain until we figure out how to scale these appropriately.

Change-Id: I00386f20f35d7fabb19aba94c8162f8aee64ef2b

Change-Id: Ib5106d4772450f8026f823dd743f162ab833b1d6

Change-Id: I9d0efdff0c79ea4bdd660098106b64776bdd4483

Change-Id: Ie34820c1b6eaba9cf9316415a46f48af79c41646

Change-Id: I914bcc669297d3414261486bf1bfb716c2ecc804

This patch allows use of 8x8 and 4x4 ADST correctly for Intra
16x16 modes and Intra 8x8 modes when the block size selected
is smaller than the prediction mode. Also includes some cleanups
and refactoring.

Rebase.

Change-Id: Ie3257bdf07bdb9c6e9476915e3a80183c8fa005a

Change-Id: Ia1cce221f8511561b9cbd8edb7726fbc286ff243

Not all segment feature data elements are full-range powers of two, so
there are values that can be encoded that are invalid. Add a new function
to clamp values to the maximum allowed.

Change-Id: Ie47cb80ef2d54292e6b8db9f699c57214a915bc4

Support for gyp which doesn't support multiple objects in the same
static library having the same basename.

Change-Id: Ib947eefbaf68f8b177a796d23f875ccdfa6bc9dc

Change-Id: Icf8ad313c543462e523bff89690e5daa8d49bcc0

Experiments with a larger set of contexts and some
clean up to replace magic numbers regarding the
number of contexts.

The starting values and rate of backwards adaption
are still suspect and based on a small set of tests.
Added forwards adjustment of probabilities.

The net result of adding the new context and forward
update is small compared to the old context from the
legacy find_near function.  (down a little on derf but
up by a similar amount for HD)

HOWEVER.... with the new context and forward update
the impact of disabling the reverse update (which may be
necessary in some use cases to facilitate parallel decoding)
is hugely reduced.

For the old context without forward update, the impact of
turning off reverse update (Experiment was with SB off) was
Derf - 0.9, Yt -1.89, ythd -2.75 and sthd -8.35. The impact was
mainly at low data rates.

With the new context and forward update enabled the impact
for all the test sets was no more than 0.5-1% (again most at
the low end).

Change-Id: Ic751b414c8ce7f7f3ebc6f19a741d774d2b4b556

A patch on compound inter-intra prediction.

In compound inter-intra prediction, a new predictor for
16x16 inter coded MBs are obtained by combining a single
inter predictor with a 16x16 intra predictor, in a manner
that the weight varies with distance from the top/left
boundary. The current search strategy is to combine the best
inter mode with the best intra mode obtained independently.

Results so far:

derf +0.31%
yt +0.32%
std-hd +0.35%
hd +0.42%

It is conceivable that the results would improve somewhat
with a more thorough search strategy where all intra modes
are searched given the best mv, or even a joint search for
the best mv and the best intra mode.

Change-Id: I7951f1ed0d6eb31ca32ac24d120f1585bcd8d79b

Silenced a few VS compiler warnings.

Change-Id: I658ea409c36c05cd11042675e2e42ccde0ef2420

If the SEG_LVL_MODE is an intra mode, then the reference frame must be
INTRA_FRAME.

Change-Id: I2cdeeac3780c077c74b39ce89a528bc280674231

This fix ensures that the forward prob update is not turned off for
motion vectors.

Change-Id: I0b63c9401155926763c6294df6cca68b32bac340

Change-Id: Ia1eddb108ec463835e9de8769572d698e21bca49

This change is a fix / extension of the newbestrefmv
experiment. As such it is presented without IFDEF.

The change creates a new context for coding inter modes
in vp9_find_mv_refs(). This replaces the context that
was previously calculated in vp9_find_near_mvs().
The new context is unoptimized and not necessarily
any better at this stage (results pending), but eliminates
the need for a legacy call to vp9_find_near_mvs().
Based on numbers from Scott, this could help decode
speed by several %.

In a later patch I will add support for forward update of
context (assuming this helps) and refine the context as
necessary.

Change-Id: I1cd991b82c8df86cc02237a34185e6d67510698a

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

cleanup

Change-Id: I565eee40d900e0441ad211b65ac829fc5b93d94a