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
added additional motion vectors at close neighborhood of a superblock
to the list of candiate motion vectors, and removed a couple that are
further away.
The change helped std-hd set about .8% (all metrics) and smaller gain
for derf set.
Change-Id: Iaa69b98614db43420ed3fd4738d0ca5587b90045
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
Modify the decoder to return the ending position of the bool decoder and
use that as the starting position for the next frame.
The constant-space algorithm for parsing the appended frame lengths is
O(n^2), which is a potential DoS concern if n is unbounded. Revisit
the appended lengths for use as partition lengths when multipartition
support is added.
In addition, this allows decoding of raw streams outside of a container
without additional framing information, though it's insufficient to
be able to remux said stream into a container.
Change-Id: I71e801a9c3e37abe559a56a597635b0cbae1934b
Rather than building an object file directory heirarchy matching the
source tree's layout, rename the object files so that the object
file name contains the path in the source file tree. The intent here
is to allow two files in different parts of the source tree to have
the same name and still not collide when put into an ar archive.
Change-Id: Id627737dc95ffc65b738501215f34a995148c5a2
Update decode_coefs() to break when c >= eob, since it's possible that
c starts the loop from 1 and eob is 0. The loop won't terminate in that
case.
Add new get_eob() function to consistently clamp the eob based on the
segment level EOB and the block size. It's possible to code a segment
level EOB that's greater than the block size, and that leads to an
out of bounds access.
Change-Id: I859563b30414615cf1b30dcc2aef8a1de358c42d
This is in line with other cases where we disable ADST if prediction
size and transform size don't match. Before this patch, the RD loop
will use ADST for superblocks, but frame encoding/decoding won't.
Change-Id: I700368c632eb72b5e089c22ef25649d99d7697d0
There are now more than 16 possible modes so 5
bits required for segment mode feature.
Note that it is likely that the mode feature and how it is
coded will change but for now the 4 bits was a bug.
Change-Id: I63348ae3a9cc31566a656c2dc78f09f5e1a9dcc9
CONFIG_DEBUG was turning on some code to dump the reconstructed frame
to a buffer from within the decoder. Move this code to a more specific
debugging define.
Change-Id: I3ca9ea634bdbd186f2470bd644d3695ee0ab3037
Similar to 16x16 dequant and idct, based on the value of eobs, the
8x8 dequant and idct calculation was simplified to improve decorder
performance.
Combined vp9_dequant_idct_add_8x8 and vp9_dequant_dc_idct_add_8x8
to eliminate duplicate code.
Change-Id: Ia58e50ab27f7012b7379c495837c9c0b5ba9cf7f
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
Experiment to test speed trade off of reducing the
extent of the ref mv search.
Reducing the maximum number of tested candidates to 9 had
minimal net effect on quality in any of the tests sets.
Reduction to 7 has a small negative impact (worst was STD-HD
at about -0.2%).
This change is in response to the apparently high number of
decode cycles reported in regard to mv-ref selection.
Change-Id: I0e92e92e324337689358495a1ec9ccdeb23dc774
This fixes encoder/decoder mismatches with the superblock experiment
turned on whenever a superblock is encoded using the 4x4 transform.
Change-Id: Iefec7055e8d25f8efdbba66c4261bbd322d335a3
This should prevent inconsistent results between identical encodes with
the superblock experiment turned on.
Change-Id: I41a005fae53f2eb59736cc70041185fb7d63cfca
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
The altref frame is packed along with the next P frame. So that
outside of the codec there are now only two types of frames P and I.
Also, now it is one frame in and one frame out with respect to the
codec. Apart from that, all the frames are length encoded with the
length of each frame appended to the frame itself. There are
two categories of frames and each of them will look as follows:
- Packed frames (an altref along with the succeeding p frame)
- altref_frame_data | altref_lenngth | frame_data | length
- Unpacked frames (all frames other than the above)
- frame_data | length
Change-Id: If1eabf5c473f7d46b3f2d026bd30c803588c5330
Also split superblock handling code out of decode_macroblock() into
a new function decode_superblock(), for easier readability.
Derf +0.05%, HD +0.2%, STDHD +0.1%. We can likely get further gains
by allowing to select mb_skip_coeff for a subset of the complete SB
or something along those lines, because although this change allows
coding smaller transforms for bigger predictors, it increases the
overhead of coding EOBs to skip the parts where the residual is
near-zero, and thus the overall gain is not as high as we'd expect.
Change-Id: I552ce1286487267f504e3090b683e15515791efa
As suggested by Yaowu, simplified 16x16 dequant and idct. In decoder,
after detoken step, we know the number of non-zero dct coefficients
(eobs) in a macroblock. Idct calculation can be skipped or simplified
based on eobs, which improves the decoder performance.
Change-Id: I9ffa1cb134bcb5a7d64fcf90c81871a96d1b4018
Creates a merge between the master and experimental branches. Fixes a
number of conflicts in the build system to allow *either* VP8 or VP9
to be built. Specifically either:
$ configure --disable-vp9 $ configure --disable-vp8
--disable-unit-tests
VP9 still exports its symbols and files as VP8, so that will be
resolved in the next commit.
Unit tests are broken in VP9, but this isn't a new issue. They are
fixed upstream on origin/experimental as of this writing, but rebasing
this merge proved difficult, so will tackle that in a second merge
commit.
Change-Id: I2b7d852c18efd58d1ebc621b8041fe0260442c21
In the variance calculations the difference is summed and later squared.
When the sum exceeds sqrt(2^31) the value is treated as a negative when
it is shifted which gives incorrect results.
To fix this we force the multiplication to be unsigned.
The alternative fix is to shift sum down by 4 before multiplying.
However that will reduce precision.
For 16x16 blocks the maximum sum is 65280 and sqrt(2^31) is 46340 (and
change).
This change is based on:
1698234 Missed some variance casts
fea3556 Fix variance overflow
Change-Id: I2c61856cca9db54b9b81de83b4505ea81a050a0f
s/([vV][pP])8/$19/
additionally dct.h was removed; declare the _c functions that are used
in the tests. the TODO for conversion to parameterized tests still
remains.
Change-Id: I73db9425a57075bbb78a92693ba6b320578981cd
there are still a couple type of warning left, which are related to
double constants assigned to float type. As those would be addressed
by the conversion of transforms into integer version. This commit
has left those un-dealt with.
Change-Id: I48fd9b489c0c27ad6b543f4177423419f929f2bb
calculate the txfm_cache difference first as both values may be
INT64_MAX with the intent that they cancel each other out.
Change-Id: I214d072458e1b24f60289974e6302af1aff7b66c
rd_pick_intra4x4mby_modes / rd_pick_intra8x8mby_modes would both use the
input value of 'rate_y' in the return calculation. In many places this
value is uninitialized. Remove the unneeded sum.
Change-Id: Icbd3df685303000301e69291c0ebc06f74bd548d
The block sizes for decoding tokens are up to 16x16, which means
eobs is within [0, 256]. Using (signed) char is not enough. Changed
eobs data type to unsigned short to fix the problem.
Change-Id: I88a7d3098e1f1604c336d6adb88ffec971fb03a6
