This quite large check in includes the following:

Merge in some code from Ronald (mbgraph.c) that scans a Gf/arf group.
This is used as a basis for a simple segmentation for the normal frames
in a gf/arf group. This code also uses satd functions from Yaowu.

Adds functionality for coding the latest possible position of an EOB for
blocks in the segment. (Currently 0-15 only, hence just for 4x4 dct).
Where the EOB position is 0 this acts like "skip" and the normal coding
of skip at the per mb level is disabled.

Added functions (seg_common.c) for setting and reading segment feature
elements. These may want to be optimized away at some point but while the
mecahnism is in a state of flux they provide a single location for making
changes and keep things a bit cleaner.

This is still proof of concept code. Currently the tested feature set:-

Quantizer,
Loop Filter level,
Reference frame,
Prediction Mode,
EOB end stop.

TBD:-

Add functions for setting and reading the feature...

When 8x8 transform is enabled, the decoder does an extra reconstruct
on MBs that are coded using 8x8. This commit fixed the logic around
the decoding of mb encoded with 8x8 transform.

Change-Id: I6926557c9ef00eecb375f62946f7e140c660bf6f

These changes fixes a glitch between the RTP profile and the input
partitions interface. Since there's no way for the user to know the
actual number of partitions, the decoder have to read the
multi_token_paritition bits also when input partitions mode is
enabled.

Included are also a couple of fixes for issues with independent
partitions and uninitialized memory reads.

Change-Id: I6f93b15287d291169ed681898ed3fbcc5dc81837

Patch 1 to Patch 3 is an initial implementation of 8x8 intra prediction
modes, here are with the following assumptions:
a. 8x8 has 4 prediction modes DC, H, V and TM
b. UV 4x4 block use the same mode as corresponding 8x8 area
c. i8x8 modes are enabled for key frame only for now
Patch 4:
d. removed debug code from previous patches
Patch 5:
e. added stats code to collect entropy stats and further cleaned up
Patch 6:
f. changed mode stats code to collect finer stats of modes
Patch 7:
g. normalized i8x8 modes distribution to total at 256 (8bits).
Patch 8:
h. fixed a bug in decoder and removed debug printf output.
Patch 9:
i. more cleanups to address paul's comment
Patch 10:
j. messy rebase/merges to bring the commit up to date.

Tests on HD clips encoded with all key frame showing consistent gain
on all clips and all metrics:~0.5%(psnr) and 0.6%(ssim):
http://www.corp.google.com/~yaowu/no_crawl/i8x8hd_allkey_fixedq.html

To build and test, configure with:
--enable-experimental --enable-i8x8

Change-Id: I9813fe07ae48cab5fdb5d904bca022514ad01e7f

Plumbing for tuning new segment features on and off.

Change-Id: If86cd6f103296b73030e8af7cf85c5b9bbffdbaf

Code all the features for one segment (grouped together)
then all for the next etc. etc. rather than grouping the
data by feature.

Change-Id: I2a65193b3a70aca78f92e855e35d8969d857b6dd

This data structure is  now [Segment ID][Features]
rather than [Features][Segment_ID]

I propose as a separate modification to make the experimental
bit stream reflect this such that all the features for a segment
are coded together.

Change-Id: I581e4e3ca2033bdbdef3d9300977a8202f55b4fb

Some basic plumbing added for a range of segment level features.
MB_LVL_* changed to SEG_LVL_* to better reflect meaning.

Change-Id: Iac96da36990aa0e40afc0d86e990df337fd0c50b

for SPLITMV and B_PRED modes.  Modified code to use the bmi
found in mode_info_context instead of BLOCKD.  On the decode
side, the uvmvs are calculated only when required, instead of
every macroblock.  This is WIP. (bmi should eventually be
removed from BLOCKD)
Small performance gains noticed for RT encodes and decodes.(VGA)

Change-Id: I2ed7f0fd5ca733655df684aa82da575c77a973e7

When error concealment is enabled the first key frame must
be successfully received before error concealment is activated.
Error concealment will be activated when the delta following
delta frame is received.

Also fixed a couple of bugs related to error tracking in
multi-threading. And avoiding decoding corrupt residual
when we have multiple non-resilient partitions.

Change-Id: I45c4bb296e2f05f57624aef500a874faf431a60d

This patch fixes an OOB read when error concealment is enabled and the
partition sizes are corrupt. The partition size read from the bitstream
was not being validated in EC mode.

Change-Id: Ia81dfd4bce1ab29ee78e42320abe52cee8318974

When error concealment is enabled the first key frame must
be successfully received before error concealment is activated.
Error concealment will be activated when the delta following
delta frame is received.

Also fixed a couple of bugs related to error tracking in
multi-threading. And avoiding decoding corrupt residual
when we have multiple non-resilient partitions.

Change-Id: I45c4bb296e2f05f57624aef500a874faf431a60d

This patch fixes an OOB read when error concealment is enabled and the
partition sizes are corrupt. The partition size read from the bitstream
was not being validated in EC mode.

Change-Id: Ia81dfd4bce1ab29ee78e42320abe52cee8318974

sharpness was not recalculated in vp8cx_pick_filter_level_fast

remove last_filter_type. all values are calculated, don't need to update
the lfi data when it changes.

always use cm->sharpness_level. the extra indirection was annoying.

don't track last frame_type or sharpness_level manually. frame type
only matters for motion search and sharpness_level is taken care of in
frame_init

move function declarations to their proper header

Change-Id: I7ef037bd4bf8cf5e37d2d36bd03b5e22a2ad91db

With this fix, the experimental branch now builds and encodes correctly
with the following two configure options respectively:
--enable-experimental --enable-t8x8
--enable-experimental

Change-Id: I3147c33c503fe713a85fd371e4f1a974805778bf

Please refer to previous commit messages for detailed info:
https://on2-git.corp.google.com/g/#change,5940
https://on2-git.corp.google.com/g/#change,6045

Change-Id: I8b16992f2f69c5a808ad40a3e32ef589cce7c59d

There were many instances in the code of vp8_coef_tokens and
vp8_coef_tokens-1, which was a preprocessor macro despite the naming
convention. Replace these with MAX_ENTROPY_TOKENS and ENTROPY_NODES,
respectively.

Change-Id: I72c4f6c7634c94e1fa066cd511471e5592c748da

Change-Id: Ieb2f3827ae7896ae594203b702b3e8fa8fb63d37

With this commit frames can be received partition-by-partition
from the encoder and passed partition-by-partition to the
decoder.

At the encoder-side this makes it easier to split encoded
frames at partition boundaries, useful when packetizing
frames. When VPX_CODEC_USE_OUTPUT_PARTITION is enabled,
several VPX_CODEC_CX_FRAME_PKT packets will be returned
from vpx_codec_get_cx_data(), containing one partition
each. The partition_id (starting at 0) specifies the decoding
order of the partitions. All partitions but the last has
the VPX_FRAME_IS_FRAGMENT flag set.

At the decoder this opens up the possibility of decoding partition
N even though partition N-1 was lost (given that independent
partitioning has been enabled in the encoder) if more info
about the missing parts of the stream is available through
external signaling.

Each partition is passed to the decoder through the
vpx_codec_decode() function, with the data pointer pointing
to the start of the partition, and with data_sz equal to the
size of the partition. Missing partitions can be signaled to
the decoder by setting data != NULL and data_sz = 0. When
all partitions have been given to the decoder "end of data"
should be signaled by calling vpx_codec_decode() with
data = NULL and data_sz = 0.

The first partition is the first partition according to the
VP8 bitstream + the uncompressed data chunk + DCT address
offsets if multiple residual partitions are used.

Change-Id: I5bc0682b9e4112e0db77904755c694c3c7ac6e74

Also includes a couple of error concealment bug fixes:
- the segment_id wasn't properly initialized when missing
- when interpolating and no neighbors are found, set to zero
- clear the qcoef buffer when concealing an MB

Change-Id: Id79c876b41d78b559a2241e9cd0fd2cae6198f49

If setup_token_decoder reported an internal error the memory allocated
there would not be freed in the resulting call to _remove_decompressor.

Change-Id: Ib459de222d76b1910d6f449cdcd01663447dbdf6

Declared the bmi in BLOCKD as a union instead of B_MODE_INFO.
Then removed B_MODE_INFO completely.

Change-Id: Ieb7469899e265892c66f7aeac87b7f2bf38e7a67

Change-Id: I6e5e921f03dc15a72da89a457848d519647677a3

Declared the bmi in MODE_INFO as a union instead of B_MODE_INFO.
This reduced the memory footprint by 518,400 bytes for 1080
resolutions.  The decoder performance improved by ~4% for the
clip used and the encoder showed very small improvements. (0.5%)
This reduction was first mentioned to me by John K. and in a
later discussion by Yaowu.
This is WIP.

Change-Id: I8e175fdbc46d28c35277302a04bee4540efc8d29

The error-concealer is plugged in after any motion vectors have been
decoded. It tries to estimate any missing motion vectors from the
motion vectors of the previous frame. Intra blocks with missing
residual are replaced with inter blocks with estimated motion vectors.

This feature was developed in a separate sandbox
(sandbox/holmer/error-concealment).

Change-Id: I5c8917b031078d79dbafd90f6006680e84a23412

Code cleanup.

Change-Id: Ic8b0167851116c64ddf08e8a3d302fb09ab61146

decoding

before
10.425
10.432
10.423
=10.426

after:
10.405
10.416
10.398
=10.406, 0.2% faster

encoding

before
14.252
14.331
14.250
14.223
14.241
14.220
14.221
=14.248

after
14.095
14.090
14.085
14.095
14.064
14.081
14.089
=14.086, 1.1% faster

Change-Id: I483d3d8f0deda8ad434cea76e16028380722aee2

Fixed test vector mismatch that was introduced
in the "Removed dc_diff from MB_MODE_INFO"
(Ie2b9cdf9e0f4e8b932bbd36e0878c05bffd28931)

Change-Id: I98fa509b418e757b5cdc4baa71202f4168dc14ec

ref_frame is set to INTRA_FRAME for keyframes.  The B_PRED
mode is only used in intra frames.

Change-Id: I9bac8bec7c736300d47994f3cb570329edf11ec0

The dc_diff flag is used to skip loopfiltering.  Instead
of setting this flag in the decoder/encoder, we now check
for this condition in the loopfilter.

Change-Id: Ie2b9cdf9e0f4e8b932bbd36e0878c05bffd28931

Code cleanup.  The build inter predictor functions are
redundantly checking the mode_info_context for either
INTRA_FRAME or SPLITMV.

Change-Id: I4d58c3a5192a4c2cec5c24ab1caf608bf13aebfb

A large number of functions were defined with external linkage, even
though they were only used from within one file. This patch changes
their linkage to static and removes the vp8_ prefix from their names,
which should make it more obvious to the reader that the function is
contained within the current translation unit. Functions that were
not referenced were removed.

These symbols were identified by:

  $ nm -A libvpx.a | sort -k3 | uniq -c -f2 | grep ' [A-Z] ' \
    | sort | grep '^ *1 '

Change-Id: I59609f58ab65312012c047036ae1e0634f795779

The vp8_build_intra_predictors_mby and vp8_build_intra_predictors_mby_s
functions had global function pointers rather than using the RTCD
framework. This can show up as a potential data race with tools such as
helgrind. See https://bugzilla.mozilla.org/show_bug.cgi?id=640935
for an example.

Change-Id: I29c407f828ac2bddfc039f852f138de5de888534

Change-Id: I64fa47889c54cfed094a674c49ef0996d49bdd42

Allow compiling without adding vp8/{common,encoder,decoder} to the
include paths.

Change-Id: Ifeb5dac351cdfadcd659736f5158b315a0030b6c

Change-Id: Icf4b692099d7d249fe3553852b1022b027b28e4b

we were holding on to this "just in case." purge it instead

Change-Id: I77a367b36d0821d731019f2566ecfffdae1d4b8a

A new vpx_codec_control called VP8D_GET_FRAME_CORRUPTED. The output
from the function is non-zero if the last decoded frame contains
corruption due to packet losses.

The decoder is also modified to accept encoded frames of zero length.
A zero length frame indicates to the decoder that one or more frames
have been completely lost. This will mark the last decoded reference
buffer as corrupted. The data pointer can be NULL if the length is
zero.

Change-Id: Ic5902c785a281c6e05329deea958554b7a6c75ce

Removing unused local variables causing compiler warnings in
Visual Studio.

Change-Id: I0e2096303be1fdbc01428a6e57cca9796bb32c8a

- Used three probability approach for temporal context as follows:
P0 - probability of no change if both above and left not changed
P1 - probability of no change if one of above and left has changed
P2 - probability of no change if both above and left have changed

In addition, a 1 bit/frame has been used to decide whether to use temporal context or to encode directly.  The cost of using both the schemes is calculated ahead and the temporal_update flag is set if the cost of using temporal context is lower than encoding the segment ids directly.

This approach has given around 20% reduction in cost of bits needed to encode segmentation ids.

Change-Id: I44a5509599eded215ae5be9554314280d3d35405