In this commit I have added an experimental function
that tests prediction quality either side of a central position
to calculate a suggested boost number for an ARF frame.
The function is passed an offset from the current position and
a number of frames to search forwards and backwards.
It returns a forward, backward and compound boost number.
The new code can be deactivated using #define NEW_BOOST 0
In its current default state the code searches forwards and backwards
from the proposed position of the next alt ref.
The the old code used a boost number calculated by scanning forward
from the previous GF up to the proposed alt ref frame position.
I have also added some code to try and prevent placement of a gf/arf
where there is a brief flash.
Change-Id: I98af789a5181148659f10dd5dd2ff2d4250cd51c
Adding support in the encoder for generating
independent residual partitions by forcing
equal probabilities over the prev coef entropy
contexts.
Change-Id: I402f5c353255f3ca20eae2620af739f6a498cd21
This reverts commit 212f618373.
Further testing shows that the overshoot accumulation/damping is too
aggressive on some clips. Allowing the accumulated overshoot to
decay and limiting to damping to golden frames shows some promise.
But some clips show significant overshoot in the buffer window, so
I think this still needs work.
Change-Id: Ic02a9ca34f55229f9cc04786f4fab54cdc1a3ef5
This patch attempts to reduce the peak bitrate hit by the encoder
when using small buffer windows.
Tested on the CIF set over 200-500kbps using these settings:
--buf-sz=500 --buf-initial-sz=250 --buf-optimal-sz=250 \
--undershoot-pct=100
Two pass encodes were tested at best quality. One pass encodes were
tested only at realtime speed 4:
--rt --cpu-used=-4
The peak datarate (over the specified 500ms window) was measured
for each encode, and averaged together to get metric for
"average peak," computed as SUM(peak)/SUM(target). This patch
reduces the average peak datarate as follows:
One pass:
baseline: 1.29715
this patch: 1.23664
Two pass:
baseline: 1.32702
this patch: 1.37824
This change had a positive effect on our quality metrics as well:
One pass CBR:
Min / Mean / Max (pct)
Average PSNR -0.42 / 2.86 / 27.32
Overall PSNR -0.90 / 2.00 / 17.27
SSIM -0.05 / 3.95 / 37.46
Two pass CBR:
Min / Mean / Max (pct)
Average PSNR -4.47 / 4.35 / 35.99
Overall PSNR -3.40 / 4.18 / 36.46
SSIM -4.56 / 6.98 / 53.67
One pass VBR:
Min / Mean / Max (pct)
Average PSNR -5.21 / 0.01 / 3.30
Overall PSNR -8.10 / -0.38 / 1.21
SSIM -7.38 / -0.11 / 3.17
(note: most values here were close to the mean, there were a few
outliers on files that were very sensitive to golden frame size)
Two pass VBR:
Min / Mean / Max (pct)
Average PSNR 0.00 / 0.00 / 0.00
Overall PSNR 0.00 / 0.00 / 0.00
SSIM 0.00 / 0.00 / 0.00
Neither one pass or two pass CBR mode adheres particularly strictly
to the short term buffer constraints, and two pass is less
consistent, even in the baseline commit. This should be addressed
in a later commit. This likely will hurt the quality numbers, as it
will have to reduce the burstiness of golden frames.
Aside: My work on this commit makes it clear that we need to make
rate control modes "pluggable", where you can easily write a new
one or work on one in isolation.
Change-Id: I1ea9a48f2beedd59891f1288aabf7064956b4716
vp8_fast_quantize_b_pair_neon function added to quantize
two adjacent blocks at the same time to improve performance.
- Additional 3-6% speedup compared to neon optimized fast
quantizer (Tanya VGA@30fps, 1Mbps stream, cpu-used=-5..-16)
Change-Id: I3fcbf141e5d05e9118c38ca37310458afbabaa4e
Misplaced #endif caused first_time_stamp_ever to only be initialized if
CONFIG_INTERNAL_STATS was set.
Change-Id: I2296a4ab00f7dfb767583edcc5d59b94f48c0621
in onyx_if.c update_reference_frames() make
sure that frame buffer indexes are not equal
before preforming a buffer copy. If two frames
share the same buffer the flags will already be
set correctly.
Change-Id: Ida9b5516d08e3435c90f131d2dc19d842cfb536e
Test showed using hex search in realtime mode largely speed up
encoding process, and still achieves similar quality like the
diamond search we have. Therefore, removed the diamond search
option.
Change-Id: I975767d0ec0539f9f6ed7fdfc09506e39761b66c
fixed a bug where active_worst_quality could be set
below active_best_quality which could result in an
infinite loop.
Change-Id: I93c229c3bc5bff2a82b4c33f41f8acf4dd194039
This patch collects the twopass specific memebers of VP8_COMP into a
dedicated struct. This is a first step towards isolating the two pass
rate control and aids readability by decorating these variables with
the 'twopass.' namespace. This makes it clear to the reader in what
contexts the variable will be valid, and is a hint that a section of
code might be a good candidate to move to firstpass.c in later
refactoring. There likely will be other rate control modes that need
their own specific data as well.
This notation is probably overly verbose in firstpass.c, so an
alternative would be to access this struct through a pointer like
'rc->' instead of 'cpi->firstpass.' in that file. Feel free to make
a review comment to that effect if you prefer.
Change-Id: I0ab8254647cb4b493a77c16b5d236d0d4a94ca4d
