John Koleszar [Wed, 20 Mar 2013 17:22:20 +0000 (10:22 -0700)]
Add an in-loop deringing experiment
Adds a per-frame, strength adjustable, in loop deringing filter. Uses
the existing vp9_post_proc_down_and_across 5 tap thresholded blur
code, with a brute force search for the threshold.
Results almost strictly positive on the YT HD set, either having no
effect or helping PSNR in the range of 1-3% (overall average 0.8%).
Results more mixed for the CIF set, (-0.5 min, 1.4 max, 0.1 avg).
This has an almost strictly negative impact to SSIM, so examining a
different filter or a more balanced search heuristic is in order.
Deb Mukherjee [Wed, 13 Mar 2013 18:03:17 +0000 (11:03 -0700)]
Modeling default coef probs with distribution
Replaces the default tables for single coefficient magnitudes with
those obtained from an appropriate distribution. The EOB node
is left unchanged. The model is represeted as a 256-size codebook
where the index corresponds to the probability of the Zero or the
One node. Two variations are implemented corresponding to whether
the Zero node or the One-node is used as the peg. The main advantage
is that the default prob tables will become considerably smaller and
manageable. Besides there is substantially less risk of over-fitting
for a training set.
Various distributions are tried and the one that gives the best
results is the family of Generalized Gaussian distributions with
shape parameter 0.75. The results are within about 0.2% of fully
trained tables for the Zero peg variant, and within 0.1% of the
One peg variant.
The forward updates are optionally (controlled by a macro)
model-based, i.e. restricted to only convey probabilities from the
codebook. Backward updates can also be optionally (controlled by
another macro) model-based, but is turned off by default. Currently
model-based forward updates work about the same as unconstrained
updates, but there is a drop in performance with backward-updates
being model based.
The model based approach also allows the probabilities for the key
frames to be adjusted from the defaults based on the base_qindex of
the frame. Currently the adjustment function is a placeholder that
adjusts the prob of EOB and Zero node from the nominal one at higher
quality (lower qindex) or lower quality (higher qindex) ends of the
range. The rest of the probabilities are then derived based on the
model from the adjusted prob of zero.
Paul Wilkins [Fri, 22 Mar 2013 15:47:17 +0000 (15:47 +0000)]
Disable zero bin mode boost.
As things stand the zero bin mode boost is hurting somewhat.
In part this seems to be because the boost applied as is
interferes with the rd mode selection loop.
Average gains (derf 0.072, yt 0.243, ythd 0.179 std-hd 0.212%)
Dmitry Kovalev [Thu, 21 Mar 2013 19:51:57 +0000 (12:51 -0700)]
Changing initialization order of mb_to_top_edge & mb_to_bottom_edge
Making consistent initialization of mb_to_{top,botton,left,right}_edge
variables after set_mb_row & set_mb_col calls. A little bit of code cleanup
additionally.
Yunqing Wang [Fri, 15 Mar 2013 18:33:10 +0000 (11:33 -0700)]
Optimize 8x8 idct function
Wrote sse2 functions of vp9_short_idct8x8 and vp9_short_idct10_8x8.
Compared to c version, the sse2 version is 2X faster. The decoder
test didn't show noticeable gain since 8x8 idct doesn't take much
of decoding time (less than 1% in my test).
John Koleszar [Thu, 14 Mar 2013 21:36:08 +0000 (14:36 -0700)]
Replace scaling byte with explicit display size
If the intended display size is different than the size the frame is
coded at, then send that size explicitly in the bitstream. Adds a new
bit to the frame header to indicate whether the extra size fields
are present.
Deb Mukherjee [Sat, 16 Mar 2013 16:26:52 +0000 (09:26 -0700)]
Context-pred fix to not use top/left on edges
This fix resolves some of the mismatch issues being seen
recently. While this is the right thing to do when tiling
is used for this experiment, it is not the underlying cause
of the the mismatches.
Something else is causing writing outside of the allowable
frame area in the encoder leading to this mismatch.
John Koleszar [Sat, 16 Mar 2013 00:26:24 +0000 (17:26 -0700)]
Fix use of NaN in firstpass
If the second reference is better than the first in the long term,
it was possible to try to take the fractional exponent of a
negative number, giving an undefined result.
John Koleszar [Thu, 14 Mar 2013 00:09:05 +0000 (17:09 -0700)]
Fix pulsing issue with scaling
Updates the YV12_BUFFER_CONFIG structure to be crop-aware. The
exiting width/height parameters are left unchanged, storing the
width and height algined to a 16 byte boundary. The cropped
dimensions are added as new fields.
This fixes a nasty visual pulse when switching between scaled and
unscaled frame dimensions due to a mismatch between the scaling
ratio and the 16-byte aligned sizes.
John Koleszar [Wed, 13 Mar 2013 19:15:43 +0000 (12:15 -0700)]
Add VP9_GET_REFERENCE control
This is like VP8_COPY_REFERENCE, but returns a pointer to the reference
frame rather than a copy of it. This is useful when the application
doesn't know what the size of the reference is, as is the case when
scaling is in effect.
John Koleszar [Wed, 13 Mar 2013 02:03:05 +0000 (19:03 -0700)]
fix superframe index marker masks
The superframe index marker byte carries data in the lower 5 bits. Only the
upper 3 should be used as part of the mask to detect it. By masking with
0xf0, the previous code was incorrect for frames over 65k bytes.
John Koleszar [Tue, 12 Mar 2013 23:33:38 +0000 (16:33 -0700)]
fix superframe index with lagged encoding
If a superframe (ARF) is generated while flushing the lagged frames
at the end of the clip, the buffer pointer wasn't being properly
updated to account for the size of the index, causing the next
frame to overwrite the index on the previous frame.
John Koleszar [Tue, 12 Mar 2013 21:30:18 +0000 (14:30 -0700)]
disambiguate superframe index in vp9_stop_encode()
If the bool-coded partition naturally ends in a byte that matches the
superframe index marker, it could lead to a parse error. This commit
ensures that if such a marker is seen, it is padded out with an
additional zero byte to disambiguate it.
Paul Wilkins [Tue, 12 Mar 2013 15:33:40 +0000 (15:33 +0000)]
Change buffer update rules on ARF overlay.
When coding the frame that corresponds to the midpoint frame
defining an ARF, do not update the last reference frame buffer.
Previously this buffer was updated meaning that when coding the next
ARF all the reference buffers were the same (or nearly so).
Turning the update off means that the frame before is still available
as an alternative predictor and for use in compound prediction.
Also fixed inconsistency in test for mismatch (patch from JK).
Net average gains (derf 0.049, yt 0.163, yt-hd 0.207, std-hd 0.286)
Paul Wilkins [Wed, 6 Mar 2013 11:33:43 +0000 (11:33 +0000)]
Changes to maximum gf/arf interval.
This patch puts in an adjustment to the maximum gf/arf
interval based on the active q range. It sets a fixed
baseline maximum of 16 but can drop this down to 12 at
lower q. This required some re-ordering in the first pass
code to insure we have a Q range estimate before defining
the first gf sequence.
The main gains seed are int he STD hd set on 50fps clips
where previously the interval could rise as high as 25.
On the std hd clip the gains are around 2.8% with limit set
to 300 frames.
When combined with the one shot rate control flags we get
combined of:
derf 1.55% (limit300), yt 7.25%, hd 5.17% std-hd 5.84% (limit300)
John Koleszar [Sun, 10 Mar 2013 20:39:30 +0000 (13:39 -0700)]
Optimize vp9_tree_probs_from_distribution
The previous implementation visited each node in the tree multiple times
because it used each symbol's encoding to revisit the branches taken and
increment its count. Instead, we can traverse the tree depth first and
calculate the probabilities and branch counts as we walk back up. The
complexity goes from somewhere between O(nlogn) and O(n^2) (depending on
how balanced the tree is) to O(n).
Only tested one clip (256kbps, CIF), saw 13% decoding perf improvement.
Note that this optimization should port trivially to VP8 as well. In VP8,
the decoder doesn't use this function, but it does routinely show up
on the profile for realtime encoding.
Yunqing Wang [Fri, 8 Mar 2013 18:54:30 +0000 (10:54 -0800)]
Add vp9_idct4_1d_sse2
Added SSE2 idct4_1d which is called by vp9_short_iht4x4. Also,
modified the parameter type passed to vp9_short_iht functions to
make it work with rtcd prototype.
Jingning Han [Wed, 6 Mar 2013 20:02:15 +0000 (12:02 -0800)]
Extend diff MV limit from +/-256 to +/-1024
Increase the motion search range by 4x. Change MV_CLASS tree of the
entropy coding to allow two additional mv classes to cover the
extended motion vector limit. The codec determines the effective
motion search range conditioned on the actual frame dimension.
It provides coding gains:
stdhd 0.39%
yt 0.56%
hd 0.47%
Major coding performance gains are packed in several sequences with
intense motion activities, e.g., ped_1080p gains 7% at high bit-rates,
and on average 3%.
TODO: Need to further tune the rate control and motion search units.
This also changes the RD search to take account of the correct block
index when searching (this is required for ADST positioning to work
correctly in combination with tx_select).
Yunqing Wang [Thu, 7 Mar 2013 17:15:32 +0000 (09:15 -0800)]
Fix issue in add_residual intrinsic function
Yaowu found this function had a compiling issue with MSVC because
of using _mm_storel_pi((__m64 *)(dest + 0 * stride), (__m128)p0).
To be safe, changed back to use integer store instruction.
Also, for some build, diff could not always be 16-byte aligned.
Changed that in the code.
Deb Mukherjee [Wed, 20 Feb 2013 18:16:24 +0000 (10:16 -0800)]
Coding con-zero count rather than EOB for coeffs
This patch revamps the entropy coding of coefficients to code first
a non-zero count per coded block and correspondingly remove the EOB
token from the token set.
STATUS:
Main encode/decode code achieving encode/decode sync - done.
Forward and backward probability updates to the nzcs - done.
Rd costing updates for nzcs - done.
Note: The dynamic progrmaming apporach used in trellis quantization
is not exactly compatible with nzcs. A suboptimal approach has been
used instead where branch costs are updated to account for changes
in the nzcs.
Paul Wilkins [Tue, 26 Feb 2013 16:53:03 +0000 (16:53 +0000)]
Added stricter Q control flag.
Added a variant of the one shot maxQ flag
for two pass that forces a fixed Q for the
normal inter frames. Disabled by default.
Also small adjustment to the Bits per MB
estimation.
Change-Id: I87efdfb2d094fe1340ca9ddae37470d7b278c8b8
projects / libvpx / log