When the frame is intra coded only, the encoder takes the RD
coding flow. Hence the function set_mode_info is not practically
in use. This commit removes it and the associated conditional
branches.
Change-Id: I1e42659ceb55b771ba712d1cdecacb446aa6460d
Before encoding a frame, calculate and store each 16x16 block's
variance of source difference between last and current frame.
Find partitioning threshold T for the frame from its variance
histogram, and then use T to make partition decisions.
Comparing with fixed 16x16 partitioning, rtc set test showed an
overall psnr gain of 3.242%, and ssim gain of 3.751%. The best
psnr gain is 8.653%.
The overall encoding speed didn't change much. It got faster for
some clips(for example, 12% speedup for vidyo1), and a little
slower for others.
Also, a minor modification was made in datarate unit test.
Change-Id: Ie290743aa3814e83607b93831b667a2a49d0932c
This commit enables an adaptive transform size selection method
for speed -6. It uses largest transform size when the sse is more
than 4 times of variance, i.e., most energy is compacted in the
DC coefficient. Otherwise, use the default TX_8X8. It improves
the compression efficiency for rtc set of speed -6 by 0.8%, no
speed change observed.
Change-Id: Ie6ed1e728ff7bf88ebe940a60811361cdd19969c
This patch allows the encoder to skip the partition search for the
frame if it is an inter frame and only zero motion vectors have
been detected in the first pass. The partition size is directly
assigned according to the difference variance.
Borg tests show overall little performance changes in term of PSNR
(derf -0.027%, yt 0.152%, hd 0.078%, stdhd 0%). The worst case of
PSNR loss is -0.514% from yt. The best PSNR gain is 4.293% from yt.
The second pass encoding speedup for slideshow clips is 15%-40%.
Change-Id: I881f347d286553ee5594a9ea09ba1a61ac684045
In real-time speed 6, no partition search is done. The inter
prediction results got from picking mode can be reused in the
following encoding process. A speed feature reuse_inter_pred_sby
is added to only enable the resue in speed 6.
This patch doesn't change encoding result. RTC set tests showed
that the encoding speed gain is 2% - 5%.
Change-Id: I3884780f64ef95dd8be10562926542528713b92c
Fix some bugs relating to the use of buffers
in the overlay frames.
Fix bug where a mid sequence overlay was
propagating large partition and transform sizes into
the subsequent frame because of :-
sf->last_partitioning_redo_frequency > 1 and
sf->tx_size_search_method == USE_LARGESTALL
Change-Id: Ibf9ef39a5a5150f8cbdd2c9275abb0316c67873a
This commit enables a fast path computational flow for forward
transformation. It checks the sse and variance of prediction
residuals and decides if the quantized coefficients are all
zero, dc only, or more. It then selects the corresponding coding
path in the forward transformation and quantization stage.
It is currently enabled in rtc coding mode. Will do it for rd
coding mode next.
In speed -6, the runtime for pedestrian_area 1080p at 1000 kbps
goes down from 14234 ms to 13704 ms, i.e., about 4% speed-up.
Overall coding performance for rtc set is changed by -0.18%.
Change-Id: I0452da1786d59bc8bcbe0a35fdae9f623d1d44e1
In non-rd real-time mode, choosing smaller transform size in
encoding gives better video quality and good speed gain than
choosing larger transform size. This patch set tx size search
method to ALLOW_8X8, which is better than using 4x4 or other
larger sizes.
Borg tests on rtc set at speed 6 showed significant gain on quality.
PSNR gain: 11.034% and SSIM gain: 15.466%.
The speed gain is 5% - 12% for <720p clips, and 2% - 7% for
720p clips.
Change-Id: If4dc74ed2df359346b059f47fb73b4a0193ec548
Right now there is just one place to check: xd->lossless and for the first
pass there is a function is_lossless_requested().
Change-Id: I949a6834e64ce51e422e2892f097f2b871b5429a
As a side-effect, the sad unit tests for VP8 and VP9
had to be separated.
Fixes a bug in original patch:
(https://gerrit.chromium.org/gerrit/#/c/70163/8)
that was reverted due to a nightly test failure.
Change-Id: Ia2a4e9e278fd3c89d6c3c82fcc6381320ec2a8a6
Use the appropriate subblock offset mode info rather than the parent
block base, when filling mbmi in the pc tree in nonrd_use_partition.
This mimics what is done in the vertical case and what is done for
both cases in nonrd_pick_partition.
This change has little practical effect at the moment since in speed 5
rt horizontal and vertical partitions are currently only used unpaired
at edges of the picture.
Change-Id: I4632f66ca84086dac56c7d36b45ddbe38a06f42a
This commit changed to enable the encoder to adjust motion dection
speed threshold based on picture size. In addition, cpu-used 1 now
does a partition search every other frame instead of every third
frame for low resolution inputs.
The change has no quality/speed impact for 720p and above. Test
showed the change increase encoding time by between 3% to 6% for
cpu-used 2 encodiong of 360p sequences. It also has a compression
gain about .3%.
For cpu-used 2, the change resolved some very disturbing visual
artifacts in certain sequences when large block partitionings and
transforms are used as a result of copying the partition from a
previous frame.
Change-Id: Ic7fd22508cdb811d4ca935655adbf20109286cfa
The final goal is eventually to get rid of both itxm_add and fwd_txm4x4.
This patch does it in the decoder.
Change-Id: Ibb3db57efbcbb1ac387c6742538a9fcf2c6f24a5
As a side-effect, the max_sad check is removed from the
C-implementation of VP8, for consistency with VP9, and to
ensure that the SAD tests common to VP8/VP9 pass.
That will make the VP8 C implementation of sad a little slower
but given that is rarely used in practice, the impact will be
minimal.
Change-Id: I7f43089fdea047fbf1862e40c21e4715c30f07ca
This commit enables a chessboard pattern for partition search. All
the black blocks run regular partition search ranging from 8x8 to
32x32. The rest white blocks take the nearby blocks' information
to adaptively decide the effective search range.
The compression performance for rtc set at speed -5 is down by 1.5%.
For pedestrian 1080p at speed -5, the runtime goes from 41594 ms to
39697 ms, i.e., about 5% faster.
Change-Id: Ia4b96e237abfaada487c743bca08fe1afd298685
This commit enables a background detection approach for adaptive
quantizer control. It combines the cyclic refresh pattern and the
background information to determine the segment id for adaptive
quantizer selection, prior to the non-RD mode decision process.
It hence allows proper quantization information update for a more
precise rate-distortion modeling in the non-RD mode decision.
The compression performance of speed -5 for rtc set is improved
by 2.5%, at no speed change.
Change-Id: Ic3713e8ed9185b403b5b1679d19dabd57506d452
The background detection only tracks luma component. This commits
removes the frame buffer pointer retrieval for chroma components.
Change-Id: I098bd2950f5e5829ed5dc2b48568167248da7fad
This patch sets up a quad_tree structure (pc_tree) for holding all of
pick_mode_context data we use at any square block size during encoding
or picking modes. That includes contexts for 2 horizontal and 2 vertical
splits, one none, and pointers to 4 sub pc_tree nodes corresponding
to split. It also includes a pointer to the current chosen partitioning.
This replaces code that held an index for every level in the pick
modes array including: sb_index, mb_index,
b_index, ab_index.
These were used as stateful indexes that pointed to the current pick mode
contexts you had at each level stored in the following arrays
array ab4x4_context[][][],
sb8x4_context[][][], sb4x8_context[][][], sb8x8_context[][][],
sb8x16_context[][][], sb16x8_context[][][], mb_context[][], sb32x16[][],
sb16x32[], sb32_context[], sb32x64_context[], sb64x32_context[],
sb64_context
and the partitioning that had been stored in the following:
b_partitioning, mb_partitioning, sb_partitioning, and sb64_partitioning.
Prior to this patch before doing an encode you had to set the appropriate
index for your block size ( switch statement), update it ( up to 3
lookups for the index array value) and then make your call into a recursive
function at which point you'd have to call get_context which then
had to do a switch statement based on the blocksize, and then up to 3
lookups based upon the block size to find the context to use.
With the new code the context for the block size is passed around directly
avoiding the extraneous switch statements and multi dimensional array
look ups that were listed above. At any level in the search all of the
contexts are local to the pc_tree you are working on (in?).
In addition in most places code that used to call sub functions and
then check if the block size was 4x4 and index was > 0 and return
now don't preferring instead to call the right none function on the inside.
Change-Id: I06e39318269d9af2ce37961b3f95e181b57f5ed9
There is no need to initialize source/dst frame buffers at frame
level. These will be done at block coding stage. This commit hence
removes the redundant operations.
Change-Id: I11d9f2556058c6205c8e58ed53e31f78622c41b7
This commit compares the current original frame to the previous
original frame at 64x64 block level and decides if the entire
block belongs to background area. If it is in the background area,
skip non-RD partition search and copy the partition types of the
collocated block in the previous frame.
For vidyo1 in the rtc set, this makes the speed -5 coding speed
about 8% faster. The overall compression performance is down by
1.37% for rtc set.
Change-Id: Iccf920562fcc88f21d377fb6a44c547c8689b7ea
Delete code relating to the old VP8_TUNE_SSIM flag
as this code does not currently work and is largely made
redundant in VP9 by the various AQ modes.
Change-Id: I71f28e1f680573d296422254489000678552b17b
With a more approriate one vp9_setup_src_planes() as only src buffer
pointers need to be initialized here.
Change-Id: I40fac4d8b2d39eb7d0c65b9b6afab45138a13936
Calculate the difference variance between last source frame and
current source frame. The variance is calculated at 16x16 block
level. The variances are compared to several thresholds to decide
final partition sizes.
An adaptive strategy is implemented to decide using
SOURCE_VAR_BASED_PARTITION or FIXED_PARTITION based on motions
in the video. The switching test is done once every
search_type_check_frequency frames.
The selection of source_var_thresh needs to be investigated
further later.
RTC set Borg test showed 0.424% overall psnr gain, and 0.357%
ssim gain. For clips with large enough static area, the
encoding speedup is around 2% to 15%.
Change-Id: Id7d268f1d8cbca7fb8026aa4a53b3c77459dc156
This commit allows the non-RD mode decision flow to select
prediction filter type in NEWMV mode. It provides 8.14% compression
performance gains in both settings of AQ=0 and 3. The current speed
impact is about 5% to 10% slower.
Change-Id: Id66ecebf77abd8f90fb3f6a066c0e8dfb4bf1c42
Copy up to a certain bsize, otherwise set to a fixed bsize.
This helsp to reduce artifact near moving boundary caused by full partition
copy without checking motion of super-block.
This artifact can occur at speeds 3,4 in real-time mode.
Issue: https://code.google.com/p/webm/issues/detail?id=738.
Change-Id: I05812521fd38816a467f72eb6a951cae4c227931
Turns off the DISABLE_RC_LONG_TERM_MEM macro and makes other changes
in the way the bits are updated, to make 2-pass rate control track
target bitrates closer.
Change-Id: I5f3be4b11c2908e6a9a9a1dd4fcf4e65531c44d8
This commit optimizes the bit allocation for the non-RD coding flow.
It applies slightly better quantizer to the frames, where all blocks
run a non-RD partition search. Such frames typically have better
rate-distortion trade off, thus improving the reconstruction quality
for next few frames reference at reasonably low increment in rate
cost.
The coding performance for rtc set at speed -5 with error-resilient
tuned on and rate control set as cbr is improved by 19.58%. It improved
the coding speed by about 10% for a portion of local test clips.
Change-Id: I9d56696cd4359dc8136ca10aff10fff05aaa2686
This commit enables the non-RD mode decision coding flow to
adaptively apply partition search in non-refresh frame, when the
collocated block in previous frame suggests there might be a motion
activity. It refactors the update_state_rt() function to support
buffer swap of mode_info struct, thereby unifying the encoding
stage across various non-RD coding modes.
It provides 5% compression performance gains in speed -6 for rtc
test set, at about 12% speed slow down.
Change-Id: Iefa374aed5a11c4b7ff9a3ed36a98ea8bd184edb
Fix so that vp9_update_segment_aq() will use the correct (i..e, chosen)
encoding mode (from ctx struct) in update_state.
Change-Id: Icc4b66f3935fad5ec4516a4d57e843d12c365e64
This commit allows the recursive non-RD partition search to early
terminate sub search tree when the cumulative rate-distortion is
already above the best available.
Change-Id: Ifdbcbb4bee229f47fde3033200829577c9f1fc1d
This commit added a speed feature to make the logic of calculating
skip_recode on a block level more explicit. This also enable the
feature to be enabled at speed 5 where the previous logic is too
conservative, help gain back the lost speed for --rt(-5).
Change-Id: Ieb37ca3e85c2e7bda343486edf13d5f5395f2233
There were a few conflicts between the new non-RD partition search
and recent clean-up patches, which were not caught by git control.
This commit fixed these issues.
Change-Id: Ieebefbd6c19d81d0d13e3c568877d5cce2ab7797
This commit takes out the if statements on using adaptive motion
search flag. This feature is automatically enabled in non-RD mode
decision flow for variable partition types search.
Change-Id: I5a25cf9109d84d07aa61b3e02c8d32dda1e90cb0
This commit enables a recursive partition type search for non-RD
mode decisions. It allows the encoder to choose variable block
sizes in a 64x64 block based on rate-distortion modeling.
It improves speed -6 coding efficiency for rtc set by 2.4%. Most
of the gains come from 32-40dB range, where many sequences gain
about 5% to 20%. Local tests suggest there is no speed change.
Change-Id: I06300016e500a21652812b7b3b081db39a783d66
This commit reformats non-RD coding flow layout to allow mode
decision with fixed and variable block sizes.
Change-Id: I2cdd3bb9f26c499ee4a9849004fd925cdd195d09
The flag x->skip_recode interacts badly with
the cpi->sf.use_nonrd_pick_mode and
cpi->sf.skip_encode_sb speed settings.
Restricting the use of the skip_decode flag when
these other speed choices are in use helps quality
for speeds 3 and 4 by a large amount with only a
small impact on speed.
Average improvmentes for 2 pass speed 4:
Derf +8.8%
Yt + 10.53%
Std-Hd +6.95%
yt-hd + 22.95%
Change-Id: I8010876d8012042a11077c92e69d813c3dfa58eb
