Jingning Han [Mon, 15 Oct 2018 18:48:39 +0000 (11:48 -0700)]
Add frame_gop_index to GF_GROUP
Add frame_gop_index to track the frame offset within a group of
picture. This reworks the GOP frame offset calculation and use
case. The coding stats remain identical.
Jingning Han [Mon, 15 Oct 2018 17:11:57 +0000 (10:11 -0700)]
Add encoder side frame buffer for tpl model
Add an encoder side reference frame buffer pool to store the
reference frames for tpl model. This servces as an intermediate
step to support multi-layer ARF system. The buffer memory size will
be optimized afterwards.
Jingning Han [Thu, 11 Oct 2018 19:16:01 +0000 (12:16 -0700)]
Refactor tpl model setup to support multi-layer ARF setup
Generalize the tpl model framework to support the newly designed
GOP structure system. The existing tpl model assumes single layer
ARF.
This design will separate the tpl model operation for GOP with
and without ARF cases. When a GOP has ARF, the maximum lookahead
offset would upper limit the needed frame buffer to build the
tpl model for the entire GOP. When a GOP does not have ARF, we
would use the temporal model in a different approach.
The first step will focus on GOP with ARF. All the tpl model related
operation will only be triggered by ARF frame generation.
Yunqing Wang [Fri, 12 Oct 2018 19:25:36 +0000 (12:25 -0700)]
Optimize apply_temporal_filter function
This patch optimized apply_temporal_filter function. The diff^2 for each
pixel in the 16x16 block is calculated once beforehand, so that we don't
calculate it multiple times while evaluating a pixel's neighbors. This
would speed up the function.
Yunqing Wang [Thu, 11 Oct 2018 22:13:47 +0000 (15:13 -0700)]
Make 4-tap interp filter coefficients even numbers
This CL modified 4-tap interp filter coefficients to be even numbers,
which would help in writing 4-tap filter SIMD optimizations. The coding
performance change was negligible. Speed 1 borg test showed:
avg_psnr: ovr_psnr: ssim:
lowres: -0.003 -0.012 -0.017
midres: 0.029 0.018 0.043
hdres: 0.024 0.044 0.033
Reason for revert: <INSERT REASONING HERE>
Regression in webrtc perf test
Original change's description:
> vp8: Increase rate threshold for overshoot-drop
>
> Increase the rate threshold for the dropping when
> overshoot is detected during encoding. This helps
> to prevent some unneccessary drops for hard content.
>
> Change-Id: I258bf33883d46347efd44e1e192cb25c444d05fe
Jingning Han [Wed, 10 Oct 2018 21:52:30 +0000 (14:52 -0700)]
Call tpl model build at the beginning of a GOP
The gop index 0 is default as kf / gf. The effective first coding
frame controlled by the current GOP rate allocation is indexed 1.
Call the tpl model build for the current GOP once at index 1
position. This would unify the calling system for single/multi-layer
ARF GOP structure.
Yunqing Wang [Mon, 8 Oct 2018 23:21:54 +0000 (16:21 -0700)]
Use 4-tap interp filter in speed 1 sub-pel motion search
Added the 4-tap interp filter, and used it for speed 1 sub-pel motion
search. Speed 2 motion search still used bilinear filter as before.
Speed 1 borg test showed good bit savings.
avg_psnr: ovr_psnr: ssim:
lowres: -1.125 -1.179 -1.021
midres: -0.717 -0.710 -0.543
hdres: -0.357 -0.370 -0.342
Speed test at speed 1 showed ~10% encoder time increase, which was
partially because of no SIMD version of 4-tap filter.
Wan-Teh Chang [Mon, 8 Oct 2018 17:03:06 +0000 (10:03 -0700)]
Correct a for loop in init_ref_frame_bufs.
The cm->ref_frame_map and pool->frame_bufs arrays are of different sizes
(REF_FRAMES and FRAME_BUFFERS, respectively), so init_ref_frame_bufs()
cannot iterate over these two arrays using the same for loop.
This "misinformation" may make scan-build warn about the ref_cnt_fb()
function's use of its 'bufs' argument (Dereference of null pointer) when
we pass pool->frame_bufs to ref_cnt_fb().
Rewriting the above code as:
if (buf_idx != INVALID_IDX) {
buf = &pool->frame_bufs[buf_idx];
not only is clearer but also avoids confusing scan-build.
Angie Chiang [Thu, 4 Oct 2018 22:17:02 +0000 (15:17 -0700)]
Fix bug in prepare_nb_full_mvs
Previously, the prepare_nb_full_mvs might construct nb_full_mv with
wrong mvs (from other ref frame).
The following changes will fix the bug.
1) Let ready in TplDepStats becomes int array
2) Add parameter rf_idx
3) Use mv_arr instead of mv to build the nb_full_mv
Marco Paniconi [Wed, 3 Oct 2018 22:25:32 +0000 (15:25 -0700)]
vp8: Increase rate threshold for overshoot-drop
Increase the rate threshold for the dropping when
overshoot is detected during encoding. This helps
to prevent some unneccessary drops for hard content.
Paul Wilkins [Tue, 2 Oct 2018 15:11:14 +0000 (16:11 +0100)]
Force even arf group length where possible.
This patch tweaks the calculation of the active maximum GF interval
and also the break out clause for the GF interval loop. The changes
force the maximum and where possible the break out value to be odd
which in turn will result in an even length ARF group if ARF coding is
selected (vs GF only coding).
The primary aim was to improve coding with multi layer arf groups.
For the single layer case there are small net gains in 3 out of 4 sets
(low,md, hd) and a small net drop for the NF2K set.
For multi-layer the gains (opsnr, ssim, psnr-hvs : -ve = better) were:-
Hui Su [Sat, 29 Sep 2018 21:48:56 +0000 (14:48 -0700)]
Introduce the ml_var_partition_pruning feature
Add the ml_var_partition_pruning encoder speed feature that
uses a neural net model to prune partition-none and partition-split
search. The model uses prediction residue variance and quantization
step size as input features.
Encoding speed gain for speed 0(tested over 20 hdres clips):
QP=30 QP=40
average 17.7% 18.3%
max 24.46% 26.6%
Paul Wilkins [Thu, 27 Sep 2018 09:55:05 +0000 (10:55 +0100)]
Fix minor bug in calculation of max arf group length.
Their is no valid last boosted Q availably when estimating the maximum
group length for the first ARF group in a clip, so use a value based on
the current max q.
Paul Wilkins [Fri, 28 Sep 2018 15:54:03 +0000 (16:54 +0100)]
Adjustment of GOP intra factor for multi-layer.
This provides and alternative (still to be tuned for edge cases)
approach to adjusting the gop intra factor when multi-layer coding
is in effect that does not alter single layer coding.
Hui Su [Tue, 25 Sep 2018 19:19:53 +0000 (12:19 -0700)]
Add ml_var_partition experiment
Make partition decisions using machine learning models. The goal is to
achieve better coding quality than the variance-based parititioning
without much encoding speed loss.
To enable this experiment, use --enable-ml-var-partition for config.
When eanbled, the variance-based partitioning is replaced by this ML
based partitioing for speed 6 and above in real time mode(except low
resolution or high bit-depth).
This is badly broken and may help somewhat for multi-layer but is hurting
massively in single layer encodes.
I ran this through this morning and while it often helps in SSIM it is badly down
for global PSNR and PSNR-HVS with some clips down by 35-40%. This is in line
with previous experiments where I have found that a bigger boost helps SSIM
but hurts PSNR and PSNR HVS.
I was also working on changes to the I factor that gave some improvements
in single layer though these were based upon the active Q mostly. I also have
looked at a bug for the first group where int_lbq is not properly defined and
will submit an interim patch for this while I look for a better solution.
In the meantime I think we should revert this.
The (Global PSNR, SSIM, PSNR-HVS) for the patch as is in my runs for
single layer vs a couple of days ago seem to be (-ve is better).
Low res 0.346, -1.475, 0.239
mid res 1.581, -1.300, 1.731 (worst result down by 30-40% in psnr)
hdres 0.665, -0.712, 1.043 (worst result down by 17-19% in psnr)
NF2k 0.927, 0.111, 1.3220 (Worst result down by 5-7% in psnr)
Jingning Han [Fri, 28 Sep 2018 04:01:08 +0000 (21:01 -0700)]
Add MID_OVERLAY_UPDATE frame type
Add a MID_OVERLAY_UPDATE abstract to support multi-layer
ARF-Overlay frame based approach. When setting the frame update
type to be USE_BUF_FRAME, the encoder will use show_existing_frame
to process the intermediate ARF frames. When setting the frame
update type to be MID_OVERLAY_UPDATE, the intermediate ARF frames
will go through an overlay frame for display.
Hui Su [Thu, 27 Sep 2018 17:12:55 +0000 (10:12 -0700)]
Fix a loophole in nonrd_pick_partition()
In some rare cases, all possible paritions may be skipped during RD
search. The patch makes the encoder do rectangular partition search if
both partition-none and partition-split are not allowed.
Tested on the rtc and ytlivehr testsets with speed 5 and 7, no coding
stats changes were observed.
Jingning Han [Wed, 26 Sep 2018 23:34:16 +0000 (16:34 -0700)]
Adapt GOP size threshold to the allowed layer depth
Increase the total prediction error budget linearly with the
allowed ARF layer depth. This in general improves the compression
performance, but does hit corner cases on a few clips at very
low bit-rate range (corresponding to 26 - 28 dB range). To mitigate
such problem, we temporarily work around this problem by limiting
the first GOP size to be ~8 so as to not drain up the bit resource.
The overall compression performance improvements over the current
multi-layer ARF system in speed 0 are:
projects / libvpx / log