This function is given a bsize and an mi array and has to figure out
what partition to use to divide the given bsize in the direction of
the sizes it finds in the mi array. (Since each block size can be
reached by only one sequence of partitions, this can be done
unambiguously)

The previous version was correct, working by looking up entries in the
partition_lookup array. Unfortunately, that lookup isn't quite enough
when CONFIG_EXT_PARTITION_TYPES is true, so it then had to do some
slightly confusing computations to fix things up after the fact.

The new version should be more self-explanatory and doesn't work by
looking things up in a magic array. It looks up the width and height
corresponding to bsize and compares them with the width and height
corresponding to the sb_type at mi_row,mi_col in the mi array. When
CONFIG_EXT_PARTITION_TYPES is false, this is all you need, and the
four corresponding cases can be found by a lookup in an array of 4
elements.

With extended partition types and a sufficiently large block, you have
to do a bit more searching. For example, if bsize is BLOCK_16X16 and
the subsize is BLOCK_8X8, the partition might be PARTITION_SPLIT, but
it might be one of PARTITION_HORZ_A or PARTITION_VERT_A instead. The
new code adds some comments to explain what's going on.

A nice side-effect of rewriting get_partition in this way is that it
lets us completely dispense with the partition_lookup array.

The patch also fixes comments for the A/B extended partitions in
enums.h, which were slightly backwards (a "horizontal split means two
blocks vertically above one another)

Change-Id: I4b48189103aa63e1859f25a15d7690d53ca7baf5

Change-Id: Ia84ea2f4e855671f5a29058cc7a6b5ba9e6bfef9

Automatic rebasing didn't pick up that an extra instance of the
EC_SMALLMUL flag was added in commit 8711cf5f.

However, that commit also broke CONFIG_ANS, since the CDF
probabilities are not inverted in that case. This patch fixes both
issues.

Change-Id: I85b3eb8a4be5b7a392f2f872fc4a90f3fdbf2727

Change-Id: Ie67266538db41c6aa7d79a5c270c26c021583c48

Test results:
akiyo	    -0.05%
bowing	    -0.072%
bridge	    -0.042%
bus	    -0.156%
coastguard  -0.645%
container   -0.087%
deadline     0.007%
flower       0.02%
football    -0.009%
foreman      0.03%
hall         0.087%
highway     -0.041%
husky       -0.031%
mad900       0.015%
mobile      -0.007%
mother       0.012%
news         0.039%
pamphlet     0.061%
paris       -0.003%
sign        -0.148%
silent       0.003%
students    -0.009%
tempete     -0.061%
waterfall    0.666

Change-Id: I96c2fd3a6fbc5f8e5cf7f3b881ef89335e58d5ac

Enable the use of motion field estimation in the dynamic motion
vector referencing system. With default experiments on, it improves
the compression performance:

lowres 1.2%
midres 1.5%

Change-Id: Ifc5b15a7239b5c3212ea50f326ab99d372034658

Add frame index to the deocded frames. Store such information to
the reference frame buffer pool. This design allows each frame
to know its index in natural order, as well as its reference
frames positions.

Change-Id: I5bb36928dc5750a4fdcc582dca0d244d6482f400

When updating default_partition_cdf, this sums the probabilities that
were divided evenly across the pairs PARTITION_HORZ_A/PARTITION_HORZ_B
and PARTITION_VERT_A/PARTITION_VERT_B. Those summed probabilities now
get distributed evenly across the triples you get by adding
PARTITION_HORZ_4 and PARTITION_VERT_4, respectively.

Rather than implement 2X8/8X2 blocks for now, ss_size_lookup returns
4X8/8X4 block sizes to use as chroma transform sizes for 4X16/16X4
blocks.

The changes in setup_pred_plane and set_skip_context are because this
is presumably the first time we've had to deal with 16x4 or 4x16
blocks. Since BLOCK_16X4 is not less than BLOCK_8X8, the existing
logic didn't work (and the "shuffle back one" logic should probably be
done for small widths and heights separately).

Change-Id: If28d8954da42d6c726f2bcce2cb5242154b0870c

When 64x64 transforms are enabled, it should return TX_64x64.

Midres set:
Small PSNR improvement overall (-0.061%),
But 3 clips have large gains (-1.0% to -0.4% range)

Change-Id: Ic2a1f0213449f81213219479c6b6aa0acfaac2e7

This will speed up lv_map by 4.3%

Change-Id: I886f67b9f1ae2e5f567e114fa34cf3ba437b8381

BUG=aomedia:685

Change-Id: I8490af713c53e8c420ef9dffa7c27bb71bbfca54

Avoid changing the public API based on an experiment flag:

- Remove aom_config.h include from aom_image.h.
- Unconditionally include the existing API additions.
- Add some missing doc comments (silences Doxygen warnings).
- Return an error when using ctrl flags that require
  CONFIG_COLORSPACE_HEADERS when it's not enabled.
- Move colorspace_headers to the correct section of configure.
- Move CONFIG_COLORSPACE_HEADERS to the correct section of
  aom_config_defaults.cmake.
- clang-format style check appeasement

Change-Id: I7b5d72c6f9f1a5561409d7813ba59180d98d8805

This experiment is now adopted as it was cleared by Tapas.

Note: Palette use can still be controlled by command-line option
"--tune-content=..." in 'aomenc'.

Change-Id: I832f49f20f60c34bdef5b424755849c496687e87

Change-Id: Iec7969ffd8f53ca2f4eefd1d757cfec7b3bde131

Also add another default probabilities and for two-modes

Change-Id: Ia503301e6d8e89c8d7c945ff25588807107d4807

Name changes and code moves to bring code more in line with the
design doc and an upcoming single-pass patch.  No functional changes.

Change-Id: I2bccd58c644e534b139f420b623390aa971fbdb0

Change-Id: I44bc9d8887526a5ee92bf79730fa3ce6c73b160b

Because frame contexts now follow reference frames, explicit resets
are no longer necessary, but can simply happen at the same time
as reference frame resets.

Change-Id: Idbed3794e3ed52fa298346943a3014fa1ca23897

This stores frame contexts alongside a reference frame, and always
uses the frame in reference slot 0 (LAST_FRAME) as the source of
the frame context.

The encoder could then reorder reference frames as to control
which frame context is used, however currently it does not.

Low Latency AWCY result:

   PSNR | PSNR Cb | PSNR Cr | PSNR HVS |    SSIM | MS SSIM | CIEDE 2000
-0.1438 |  0.4161 |     N/A |   0.0386 | -0.0281 |  0.0453 |     0.2514

https://arewecompressedyet.com/?job=before-frame-context-signaling%402017-06-07T23%3A20%3A49.473Z&job=after-frame-context-signaling%402017-06-07T23%3A21%3A36.117Z

Change-Id: I4f6f9b12cb403573efbf9e5c3077d62f5dedc467

For some background, see this previous change in Gerrit[0]. What's
going on here is that we only want to use a previous frame for motion
vector prediction if the encoded sizes match. When scaling with
superres, this means the size before upscaling.

To check this correctly, we need to check prev_frame's width/height
and compare it with the current frame. Without superres, prev_frame's
width/height is stored in y_crop_width/y_crop_height so we can check
that way. With superres, those numbers are after the scaling, so can't
be compared with cm->width and cm->height.

The previous code worked around this by comparing with cm->last_width
and cm->last_height. That works because these are the width/height for
the last encoded and shown frame and that frame *is* prev_frame if
last_show_frame is true. Since this is the only case when we want to
use prev_frame, they are the numbers we need.

This patch simplifies the logic by storing the width/height in
RefCntBuffer before any scaling and then checking that they match.

The check for whether we can use motion vectors from a previous frame
is factored out into a pair of inline functions in the
header. frame_might_use_prev_frame_mvs() is true if it's possible that
this frame could use motion vectors from a previous frame. This
doesn't use knowledge of what prev_frame is: it just checks we're not
in error resilient mode and aren't a keyframe. When this is true, a
flag is signaled in the bitstream to say whether we actually want to
use motion vectors from the previous frame.

The second function, frame_can_use_prev_frame_mvs, is true if the
current frame / previous frame pair is suitable for sharing motion
vectors. This is a stricter test: the previous frame needs to be
have been shown and not to have been intra_only, and it needs to have
the same width/height as the current frame.

If the re-assignment of prev_frame (just before the calls to
frame_can_use_prev_frame_mvs()) were removed in some way, we could
probably combine the two functions and often save a bit per frame
header.

The other slight tidy-up in the patch is to move re-allocation of the
mvs buffer into onyxc_int.h: the code that did the allocation was
duplicated between the encoder and decoder.

[0] https://aomedia-review.googlesource.com/c/13806

BUG=aomedia:78

Change-Id: If25227fa24222fc05c56529c2ac9ddf1e1c36a84

Tile groups are now an integral part of the codec.

Change-Id: I620a88ec7a44b057d5cce0bf6cf602822a3339a9

This CL adds an extra alt-ref reference frame, namely ALTREF2_FRAME,
and designs the contexts for ALTREF2_FRAME.

Change-Id: I12fe8629b868aebf6c2b54260fca5abc38f90ae6

Added a 1-bit flag 'large_scale_tile'. If it is 0 that is the default value,
use normal tile coding in TILE_GROUPS. If it is 1, use large-scale tile
coding in EXT_TILE.

At large_scale_tile=1 case, if single-tile-decoding is required, then the
loopfilter is disabled.

Related API and unit tests were modified.

Change-Id: I3ba12dc3d80ccf1ab21543ab3b16c02282c34e3b

This patch adds support for 4:1 rectangular blocks to various common
data arrays, and adds new partition types to the EXT_PARTITION_TYPES
experiment which will use them.

This patch has the following restrictions, which can be lifted in
future patches:

  * ext-partition-types is incompatible with fp_mb_stats and supertx
    for the moment

  * Currently only 32x32 superblocks can use the new partition types

There's a slightly odd restriction about when we allow
PARTITION_HORZ_4 or PARTITION_VERT_4. Since these both live in the
EXT_PARTITION_TYPES CDF, read_partition() can only return them if both
has_rows and has_cols is true. This means that at least half of the
width and height of the block must be visible. It might be nice to
relax that restriction but that would imply a change to how we encode
partition types, which seems already to be in a state of flux, so
maybe it's better to wait until that has settled down.

Change-Id: Id7fc3fd0f762f35f63b3d3e3bf4e07c245c7b4fa

(1) Work with var-refs to remove redundant bits in ref frame
    coding;
(2) Add a new uni-directional compound reference pair:
    (LAST_FRAME, LAST3_FRAME);
(3) Redesign the contexts for encoding uni-directional reference frame
    pairs;
(4) Use aom_entropy_optimizer to collect stats for all the default
    probability setups related to the coding of reference frames.

Compared against the baseline (default enabled tools excluding ext-tx
and global-motion for encoder speed concern) with one-sided-compound,
the coding gain of ext-comp-refs + var-refs - one-sided-compound is:

lowres: avg_psnr -0.385%; ovr_psnr -0.378% ssim -0.344%
midres: avg_psnr -0.466%; ovr_psnr -0.447% ssim -0.513%

AWCY - High Latency:
   PSNR | PSNR Cb | PSNR Cr | PSNR HVS |    SSIM | MS SSIM | CIEDE 2000
-0.2758 | -0.1526 | -0.0965 |  -0.2581 | -0.2492 | -0.2534 |    -0.2118

AWCY - Low Latency:
   PSNR | PSNR Cb | PSNR Cr | PSNR HVS |    SSIM | MS SSIM | CIEDE 2000
-1.0467 | -1.4500 | -0.9732 |  -0.9928 | -1.0407 | -1.0180 |    -1.0049

Compared against the baseline (default enabled tools excluding ext-tx
and global-motion for encoder speed concern) without
one-sided-compound, the coding gain of
ext-comp-refs + var-refs - one-sided-compound is:

lowres: avg_psnr -0.875%; ovr_psnr -0.877% ssim -0.895%
midres: avg_psnr -0.824%; ovr_psnr -0.802% ssim -0.843%

Change-Id: I8de774c9a74c20632ea93ccb0c17779fa94431cb

This required moving the CDEF and lr signaling in the
uncompressed header to after segmentation is signaled.

The all_lossless logic was factored out into onyxc_int.h.

Change-Id: If8de03438d4e9f8cb49ed49b60a880962cc9d28b

Support the transform block kernel coding for rectangular
transform block size in var-tx. This integrates txk-sel with
var-tx.

Change-Id: I9a8edd84812168f56c79b78cc9af34f6304b1d54

this warning is covered by an assert and other runtime detection.
expanding the array, adding a conditional or converting the type to int
are less desirable.

BUG=aomedia:578

Change-Id: Idb6a1dec5f17db85a0e9c1d0ee372e701f4e1aa4

Extract the compution of the luma reconstructed average out of cfl_load
and into cfl_compute_average. The reconstructed luma average is stored
in the CFL_CONTEXT to avoid computing it for each transform block and
for each plane.

Results on subset1 (compared to 803bea26 with CfL)
   PSNR | PSNR Cb | PSNR Cr | PSNR HVS |    SSIM | MS SSIM | CIEDE 2000
-0.0474 | -0.1486 | -0.2931 |  -0.0358 | -0.0397 | -0.0127 |    -0.1162

Change-Id: I9e34af0fe5961ce8dbe70cb80aea2a16221d0d92

Adds a separate scale numerator for resize and superres scaling on
keyframes. They will only use this factor in their respective FIXED
modes.

Change-Id: I4ef9a5760a5423ec632d644e6c7fec674bbb46f4

Change-Id: If93f9e41c25a5885b5927e66a298c129bb844e18

This patch implements the post-encode and post-decode upscaling for the
frame superresolution experiment to work.

Upscaling happens after cdef and before loop restoration.

For now, this patch forces on random-superres.

The patch also cleans up some broken rate control hooks from VP9
days, to be brought back later when the resize and superres tools
are stable.

Change-Id: If0a8f69224dfaa0f4ae7703bd429ea2af953c7a6

Refactoring: split prediction+extension for each plane, so we can
handle luma/chroma supertx pred in different ways.
Compatibility fix: fix conflicts with cb4x4 and chroma_sub8x8, now
for chroma sub8x8 supertx, only the top-left(basic cb4x4) or the
the bottom-right(cb4x4 + chroma_sub8x8) predictor will be used
without any blending within a 8x8 unit.

Change-Id: I6cf7b12768a82d3c7e01811ada02de84af9bd8ac

Check the availability of the reference frames at the frame level at
both encoder and decoder, and if a reference frame is not available
for a specific video frame, remove the signaling of such reference
frame info at the block level.

This patch adds the consideration of the bit saving inside the RD
optimization loop.

Change-Id: I4c22f1b843b21c7d2b47e118c99c3ad615a3d4e4

Change-Id: I3ce09c03d4306c1f2a9c70aa1e82126493bc9406

This change does not impact the bitstream
  PSNR | PSNR Cb | PSNR Cr | PSNR HVS |   SSIM | MS SSIM | CIEDE 2000
0.0000 |  0.0000 |  0.0000 |   0.0000 | 0.0000 |  0.0000 |     0.0000

Change-Id: I6e131e91bad5efa345ed2542ae970eb6122eff51

Change-Id: Ideaeb52dbaf87e5a68da90cb94b0517760cb9d5c

Update and capture the effective transform block size per color
plane.

Change-Id: Ib6e0e7abb3973db6b8d511ee7c9948aaab048788

Urvang Joshi authored May 31, 2017 and James Zern committed Jun 01, 2017

Change-Id: Id2be191fb48ed8d65b452499e1a1a1f470359321

Make the txfm_above and txfm_left be processed in the unit of
miniumum transform block size. Scale the transform block step
size with respect to the mode_info step size.

Change-Id: Iee4421e005db742cd4ff7899215560063e5f68e5