Change-Id: I54acef342b8e787e05af0febd7cf0d7d10288383

Change-Id: Iff35d4b2f8f65511f80c594958c01fb4673fa033

Change-Id: I0d12f9ef9d960df0172a1377f8e5236eb6d90492

Removing redundant 'extern' keywords, fixing formatting and #include order,
code simplification.

Change-Id: I0e5fdc8009010f3f885f13b5d76859b9da511758

This patch adds column-based tiling. The idea is to make each tile
independently decodable (after reading the common frame header) and
also independendly encodable (minus within-frame cost adjustments in
the RD loop) to speed-up hardware & software en/decoders if they used
multi-threading. Column-based tiling has the added advantage (over
other tiling methods) that it minimizes realtime use-case latency,
since all threads can start encoding data as soon as the first SB-row
worth of data is available to the encoder.

There is some test code that does random tile ordering in the decoder,
to confirm that each tile is indeed independently decodable from other
tiles in the same frame. At tile edges, all contexts assume default
values (i.e. 0, 0 motion vector, no coefficients, DC intra4x4 mode),
and motion vector search and ordering do not cross tiles in the same
frame.
t log

Tile independence is not maintained between frames ATM, i.e. tile 0 of
frame 1 is free to use motion vectors that point into any tile of frame
0. We support 1 (i.e. no tiling), 2 or 4 column-tiles.

The loopfilter crosses tile boundaries. I discussed this briefly with Aki
and he says that's OK. An in-loop loopfilter would need to do some sync
between tile threads, but that shouldn't be a big issue.

Resuls: with tiling disabled, we go up slightly because of improved edge
use in the intra4x4 prediction. With 2 tiles, we lose about ~1% on derf,
~0.35% on HD and ~0.55% on STD/HD. With 4 tiles, we lose another ~1.5%
on derf ~0.77% on HD and ~0.85% on STD/HD. Most of this loss is
concentrated in the low-bitrate end of clips, and most of it is because
of the loss of edges at tile boundaries and the resulting loss of intra
predictors.

TODO:
- more tiles (perhaps allow row-based tiling also, and max. 8 tiles)?
- maybe optionally (for EC purposes), motion vectors themselves
  should not cross tile edges, or we should emulate such borders as
  if they were off-frame, to limit error propagation to within one
  tile only. This doesn't have to be the default behaviour but could
  be an optional bitstream flag.

Change-Id: I5951c3a0742a767b20bc9fb5af685d9892c2c96f

Change-Id: I0df99742029834a85c4933652b0587cf5b6b2587

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

Change-Id: I481d5df23d8a4fc650a5bcba956554490b2bd200

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

Allows switchbale filters to be used without mismatch when the
superblock experiment is on.

Also removes a spurious clamping code in decodemv.c which causes
rare encode/decode mismatches.

Change-Id: I809d9ee0b2859552b613500b539a615515b863ae

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

Change-Id: Ib947eefbaf68f8b177a796d23f875ccdfa6bc9dc

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

Change-Id: Ia1eddb108ec463835e9de8769572d698e21bca49

Change-Id: Ic084c475844b24092a433ab88138cf58af3abbe4

For non-static functions, change the prefix to vp9_. For static functions,
remove the prefix. Also fix some comments, remove unused code or unused
function prototypes.

Change-Id: I1f8be05362f66060fe421c3d4c9a906fdf835de5

This change encompasses VP8_PTR, VP8_COMP, VP8D_COMP, VP8_COMMON,
VP8Decompressor and VP8Common.

Change-Id: I514ef4ad4e682370f36d656af1c09ee20da216ad

For local symbols, make them static instead.

Change-Id: I13d60947a46f711bc8991e16100cea2a13e3a22e

Change-Id: Ie8ba934a757acec1c80ac37ab9307c9a2783254e

Also merge some duplicate code related to the superblock experiment
in the RD loop.

Change-Id: Ic93f1d4d1ed81220fd7ecf6e65da2821a215b2de

Preparation for project restructuring.
Added vp9_ prefix on some function names that have global scope.
Added static declaration on some that dont.

Change-Id: If072f78b4300e8c17cfeed82c5d17b59946dcc5e

There is a macro DEFAULT_INTERP_FILTER defined in encoder/onyx_if.c that
is set as EIGHTTAP for now - so SWITCHABLE is not really used. Ideally,
this should be SWITCHABLE but that would make the encoder quite a bit slower.
We will change the default filter to SWITCHABLE once we find a faster way to
search for switchable filters.

Change-Id: Iee91832cdc07e6e14108d9b543130fdd12fc9874

Packs the bitstream with each mb's residual following its mode/mv
information.

TODO: There are still a few fields that should be packed into partition
0 but are included in partition 1, due to them being serialized from
write_kfmodes/pack_inter_mode_mvs, which execute after the first
partition is finalized. These need to be separated out into a separate
function, similar to mb_mode_mv_init() in decodemv.c.

Change-Id: I43a46c363601ab36954d07ebe498760e1e2e3af4

This commit adds a pick_sb_mode() function which selects the best 32x32
superblock coding mode. Then it selects the best per-MB modes, compares
the two and encodes that in the bitstream.

The bitstream coding is rather simplistic right now. At the SB level,
we code a bit to indicate whether this block uses SB-coding (32x32
prediction) or MB-coding (anything else), and then we follow with the
actual modes. This could and should be modified in the future, but is
omitted from this commit because it will likely involve reorganizing
much more code rather than just adding SB coding, so it's better to let
that be judged on its own merits.

Gains on derf: about even, YT/HD: +0.75%, STD/HD: +1.5%.

Change-Id: Iae313a7cbd8f75b3c66d04a68b991cb096eaaba6

Removed two macros corresponding to experiments that were
merged into the main code.

Change-Id: I894e8b509a2bb88557f9aba6f226ed7807745065

Allows for swtiching/setting interpolation filters at the MB
level. A frame level flag indicates whether to use a specifc
filter for the entire frame or to signal the interpolation
filter for each MB. When switchable filters are used, the
encoder chooses between 8-tap and 8-tap sharp filters. The
code currently has options to explore other variations as well,
which will be cleaned up subsequently.

One issue with the framework is that encoding is slow. I
tried to do some tricks to speed things up but it is still slow.
Decoding speed should not be affected since the number of
filter taps remain unchanged.

With the current version, we are up 0.5% on derf on average but
some videos city/mobile improve by close to 4 and 2% respectively.
If we did a full-search by turning the SEARCH_BEST_FILTER flag
on, the results are somewhat better.

The framework can be combined with filtered prediction, and I
seek feedback regarding that.

Rebased.

Change-Id: I8f632cb2c111e76284140a2bd480945d6d42b77a

The following five experiments are merged:

newentropy
newupdate
adaptive_entropy (also includes a couple of parameter changes
                  that improves results a little
                  in common/entropymode.c and encoder/modecosts.c
                  that were not merged from the internal branch)
newintramodes
expanded_coef_context

Change-Id: I8a142a831786ee9dc936f22be1d42a8bced7d270

Approximate the Google style guide[1] so that that there's a written
document to follow and tools to check compliance[2].

[1]: http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml
[2]: http://google-styleguide.googlecode.com/svn/trunk/cpplint/cpplint.py

Change-Id: Idf40e3d8dddcc72150f6af127b13e5dab838685f

Change-Id: I883b4f63559c1cf66a25016e946b1b1ae98a20da

I now see I didn't write a very long description, so let's do it
here then. We took a pretty big quality hit (0.1-0.2%) from my
recent fix of the inversion of arguments to vp8_cost_bit() in the
RD reference frame costing. I looked into it and basically the
costing prevented us from switching reference frames. This is of
course silly, since each frame codes its own prob_intra_coded, so
using last frame cost indications as a limiting factor can never
be right.

Here, I've rewritten that code to estimate costings based partially
on statistics from progress on current frame encoding. Overall,
this gives us a ~0.2%-0.3% improvement over what we had previously
before my argument-inversion-fix, and thus about ~0.4% over current
git (on derf-set), and a little more (0.5-1.0%) on HD/STD-HD/YT.

Change-Id: I79ebd4ccec4d6edbf0e152d9590d103ba2747775

Using contextual coding of the mkb_skip_coeff flag using the
values of this flag from the left and above. There is a small
improvement of about 0.15% on Derf:
http://www.corp.google.com/~debargha/vp8_results/mbskipcontext.html

Refactored to use pred_common.c by adding a new context type.

Results on HD set (about 0.66% improvement):
http://www.corp.google.com/~debargha/vp8_results/mbskipcontext_hd.html

Incliding missing refactoring to use the pred_common utilities.

Change-Id: I95373382d429b5a59610d77f69a0fea2be628278

This is a code snapshot of experimental work currently ongoing for a
next-generation codec.

The codebase has been cut down considerably from the libvpx baseline.
For example, we are currently only supporting VBR 2-pass rate control
and have removed most of the code relating to coding speed, threading,
error resilience, partitions and various other features.  This is in
part to make the codebase easier to work on and experiment with, but
also because we want to have an open discussion about how the bitstream
will be structured and partitioned and not have that conversation
constrained by past work.

Our basic working pattern has been to initially encapsulate experiments
using configure options linked to #IF CONFIG_XXX statements in the
code. Once experiments have matured and we are reasonably happy that
they give benefit and can be merged without breaking other experiments,
we remove the conditional compile statements and merge them in.

Current changes include:
* Temporal coding experiment for segments (though still only 4 max, it
  will likely be increased).
* Segment feature experiment - to allow various bits of information to
  be coded at the segment level. Features tested so far include mode
  and reference frame information, limiting end of block offset and
  transform size, alongside Q and loop filter parameters, but this set
  is very fluid.
* Support for 8x8 transform - 8x8 dct with 2nd order 2x2 haar is used
  in MBs using 16x16 prediction modes within inter frames.
* Compound prediction (combination of signals from existing predictors
  to create a new predictor).
* 8 tap interpolation filters and 1/8th pel motion vectors.
* Loop filter modifications.
* Various entropy modifications and changes to how entropy contexts and
  updates are handled.
* Extended quantizer range matched to transform precision improvements.

There are also ongoing further experiments that we hope to merge in the
near future: For example, coding of motion and other aspects of the
prediction signal to better support larger image formats, use of larger
block sizes (e.g. 32x32 and up) and lossless non-transform based coding
options (especially for key frames). It is our hope that we will be
able to make regular updates and we will warmly welcome community
contributions.

Please be warned that, at this stage, the codebase is currently slower
than VP8 stable branch as most new code has not been optimized, and
even the 'C' has been deliberately written to be simple and obvious,
not fast.

The following graphs have the initial test results, numbers in the
tables measure the compression improvement in terms of percentage. The
build has  the following optional experiments configured:
--enable-experimental --enable-enhanced_interp --enable-uvintra
--enable-high_precision_mv --enable-sixteenth_subpel_uv

CIF Size clips:
http://getwebm.org/tmp/cif/
HD size clips:
http://getwebm.org/tmp/hd/
(stable_20120309 represents encoding results of WebM master branch
build as of commit#7a159071)

They were encoded using the following encode parameters:
--good --cpu-used=0 -t 0 --lag-in-frames=25 --min-q=0 --max-q=63
--end-usage=0 --auto-alt-ref=1 -p 2 --pass=2 --kf-max-dist=9999
--kf-min-dist=0 --drop-frame=0 --static-thresh=0 --bias-pct=50
--minsection-pct=0 --maxsection-pct=800 --sharpness=0
--arnr-maxframes=7 --arnr-strength=3(for HD,6 for CIF)
--arnr-type=3

Change-Id: I5c62ed09cfff5815a2bb34e7820d6a810c23183c

Change-Id: Ibcd2b9b247ff9f83331dac47f91ec285e8955ff1

Merged in most of the current common prediction changes
that were under the #if CONFIG_COMPRED option.

Change-Id: If4e6f61dbe7b86dd449f6effbe93b5eb7e893885

Further changes to make experiments with the context
used for coding the dual pred flag easier.

Current best performing method tested on derf is a two
element context based on reference frame. I also tried
various combinations of mode and reference frame as
shown in commented out case using up to 6 contexts.

Derf +0.26 overall psnr +0.15% ssim vs original method.

Change-Id: I64c21ddec0abbb27feaaeaa1da2e9f164ebaca03

Further use of common prediction functions and experiments
with alternate contexts based on mode and reference frame.

For the Derf set using reference frame as basis of context
gives +0.18% Overall Psnr and +0.08 SSIM

Change-Id: Ie7eb76f329f74c9c698614f01ece31de0b6bfc9e

Initial modifications to make limited use of common prediction
functions.

The only functional change thus far is that updates to the probabilities are
no longer "damped". This was a testing convenience but in fact seems to
help by a little over 0.1% over the derf set.

Change-Id: I8b82907d9d6b6a4a075728b60b31ce93392a5f2e

Trial of a modified prediction function that ranks each possible
reference frame based on a combination of local usage and
frame level probability. The code is a bit cleaner and simpler.

In direct comparison with old unpredicted method with segment level
coding turned off for mode,ref & EOB the prediction gives a gain on derf
of around 0.4%. There is some further gain from bug fixes over earlier code.

With segment coding on the prediction method is slightly -ve on some very
easy clips (at low rates) due to slightly higher overheads, but better on harder
clips. Overall neutral on derf in direct comparison on latest code base, but
compared to earlier code without bug fixes about +0.7% overall psnr
+0.3% SSIM.

Change-Id: I5b8474658b208134d352d24f6517f25795490789

Extended prediction and coding of reference frame where
a subset of options are flagged as available at the segment level.

Updated copyright notices.

Switch to SAD in mbgraph code as SATD problematic for the
foreground and background separation as it can ignore large DC shifts.

Change-Id: I661dbbb2f94f3ec0f96bb928c1655e5e415a7de1

This function adds the common prediction modules,  some data structures
and a config option but does not use them.

It also corrects a bug in clearing down  the MODE_INFO border and introduces
a new element that indicates if an entry corresponds to an "in image" macro block
or is part of the border.

Change-Id: Ib69eec0876173ebe9d1de9df9537d0b2447702e0