Modified the code to facilitate bit-match tests in first pass
Added unit-tests to test the row based multi-threading behavior for bit-exactness
Change-Id: Ieaf6a8f935bb1075597e0a3b52d9989c8546d7df
This change subtracts out low complexity intra regions that are also low
error in the inter domain, in the calculation of the frame prediction decay.
The rationale here his that low complexity regions (such as sky) do not imply
high prediction decay in the same way as high error intra or neutral blocks.
The effect of this is small in most clips but in a few clips it can be > 10%.
(E.g. In to tree)
Change-Id: If67ac23d17fca14285cad2defa464c61c9ea861c
This small change replaces the frame boost check in the arf group
length break out clause with a test against a prediction decay value.
The boost value is in fact partly dependent on the decay value but
this change means that the per frame boost calculation can be adjusted
without influencing the group length calculation.
The value chosen gives a close match on all the test sets with the previous
code (on average) but it was noted that a lower threshold was slightly better
for 1080P and up and a slightly higher value for small image sizes.
Change-Id: I4d5b9f67d5b17b0d99ea3f796d3d6202fd61ee0c
The function scale_sse_threshold() returns a threshold scaled
if necessary for use with 10 and 12 bit from an 8 bit baseline.
SSE error values would be expected to rise for the 10 and 12
bit cases where there are more bits of precision.
Hence the threshold used for the test should also be scaled up.
Change-Id: I4009c98b6eecd1bf64c3c38aaa56598e0136b03d
VBR method that allows a wider Q range for the first normal frame
in each ARF group and then centers the min - max range for the rest of
the arf group on the chosen Q value for that first frame.
This allows for quite rapid adjustment of the active Q range even if the
initial estimate is poor.
In some cases where the ARF frames themselves are tending to
undershoot but the normal frames are overshooting this can still give
net undershoot. This can be corrected by allowing a larger Q delta for
arf frames but is usually is a sign that the allocation to the arfs was to
high.
Change-Id: Icec87758925d8f7aeb2dca29aac0ff9496237469
(yunqingwang)
1. Rebased the patch. Incorporated recent first pass changes.
2. Turned on the first pass unit test.
Change-Id: Ia2f7ba8152d0b6dd6bf8efb9dfaf505ba7d8edee
One of the first pass stats "new_mv_count" is no longer used in VP9,
and is removed. This also makes it easy to implement a multi-threaded
first pass. This change doesn't affect the coding performance, which
has been verified by borg tests.
Change-Id: I4c7c7bf9465fda838eb230814ef0c631c068c903
This change is a step in a larger change to the way boost and interval are
determined for ARF and Key frames.
This patch contains some pluming for the general case but focuses on the
key frame boost calculation. This now relies more heavily on the rate at
which the error score increases between the primary and secondary reference
frame. This seems to be less fragile when dealing with different frame sizes.
For example larger image formats tend in the first pass to see a higher
% of intra coded blocks and the use of this number in calculating the frame
decay factor was leading to much lower boost numbers for 4K, for example,
than the same clip coded at 2K.
This change does give overall gains but they are MUCH larger for the 4K Netflix
set. For the 4K Netflix set the average gain is around 3% with some clips > 20%
whereas for the same set at 2K the average gain is 0.5-1%.
In general for small image formats the boost is most often reduced a little whereas
4K clips the boost is increased. There are some -ve cases such as Akiyo at 352x288
where the reduced boost hurts the metrics, especially for SSIM, even while
the set as a whole improves. This is most notable at very low Q and may be the
subject of a future patch.
Some common code for KF and ARF was separated in this patch for the purposes of
tuning but may later be re-merged if appropriate.
Change-Id: Iaa15ac5a58d2be89181100d95cef6a8dc4b12d0d
Removed a couple of adjustments that no longer move the needle
much but complicate the process of tuning.
Change-Id: Ie320f5cf155e6aac14a4757ea9ada2cd59f27590
This patch sets the 16x16 src_diff to zero and ensures correct calculation
of this_error for block sizes smaller than 16x16.
Change-Id: I7b7c02d267433c9f22c8ac9b8d5df2f499175172
Added a cap on the maximum boost for an arf based on interval length.
Fixed bug where by the image size was not accounted for in determining
two of the motion breakout thresholds.
Overall small gains of 0.2-0.4% psnr but on large image format clips with
slow zooms the gain may be as much as 20% or more (e.g. in_to_tree
at 1080P)
Change-Id: Id0a47391203026742daa9c97afac5705fd8c4dfb
Added casts to remove warnings:
BUG=webm:1274
In regards to the safety of these casts they are of two types:-
- Normalized bits per (16x16) MB stored in a 32 bit int (This is safe as bits
per MB even with << 9 normalization cant overflow 32 bits. Even raw 12
bits hdr source even would only be 29 bits :- (4+4+12+9) and the encoder
imposes much stricter limits than this on max bit rate.
- Cast as part of variance calculations. There is an internal cast up to 64 bit
for the Sum X Sum calculation, but after normalization dividing by the number
of points the result will always be <= the SSE value.
Change-Id: I4e700236ed83d6b2b1955e92e84c3b1978b9eaa0
Use a measure of noise energy to adjust Q estimate and
arf filter strength.
Gains 0.3-0.5% on Lowres and |Netflix sets.
Hdres and Midres neutral.
Change-Id: Ic0de552e7b6763e70eeeaa3651619831b423e151
The scaling of the threshold for 10 and 12 bit here appears
to be in the wrong direction. For 10 and 12 bit we expect sse
values to be higher and hence the threshold used should be
scaled up not down.
Change-Id: I2678116652b539aef48100e0f22873edd4f5a786
This function seems to scale the threshold for testing an
SSE value in the wrong direction for 10 and 12 bit inputs.
Also for a true SSE the scalings should probably be << 4 and 8
Change-Id: Iba8047b3f70d04aa46d9688a824f3d49c1c58e90
Move initialization of a some new "twopass" values
to the function vp9_init_second_pass() and some other
small changes.
Remove #if GROUP_ADAPTIVE_MAXQ as this is always
enabled now.
Change-Id: I1dbec2fd7c419779848aa987c4cd7824d4df8456
Increase in the damping used in adjusting the active Q range.
This does hurt rate accuracy a little in a few extreme cases
especially if the clip is very short*, but helps metrics.
* Note that the adjustment is applied at the GF/ARF group level based
on what happened in the last group. Hence for very short clips where
the length of a single group may be a significant % of the clip length
there is still scope for some drift that cannot be accommodated.
In practice most data points in our test sets are now much closer to target
than was previously the case with default settings and in some cases are
better even than they were with the command line undershoot and overshoot
parameter was set very low (e.g. 2%). For example in bridge_close at high rates
the old mechanism was unable to adapt enough to prevent extreme overshoot.
Change-Id: I634f8f0e015b5ee64a9f0ccaa2bcfdbc1d360489
Change to the calculation of the error divisor used in
get_twopass_worst_quality(). This follows on from other
changes to the rate control that impact the output of this
function.
Change-Id: I414fa9aa1e6a68a64dccea17c3712f44b8a0c10c
Added a factor based on the bit spend in the last arf group vs the
target to adjust the choice of the active worst quality in subsequent
groups.
Helps clips where previously there was a big overshoot or undershoot
to adapt and get closer to the target rate.
Change-Id: I67034b801679b99024409489a2273ea6fe23b8e6
The use of this value is preventing rate adjustment on clips
or sections that have very little motion but high noise and
this can give rise to some sections with massive overshoot.
Change-Id: I9a65c7c1148dc5d3a7d8b23e50fc1733f3661621
Bug found by Yunqing relating to the correction for size at 8K and
above in get_twopass_worst_quality().
The basis for the correction was changed to the linear size relative to
1080P as a baseline and the adjustment has been clamped to prevent
problems at extreme images sizes.
For 1080P the results on our test sets were neutral but the low res and
mid res sets saw a small gain (0.1%-0.2% average).
I would also expect some gains on 4k and larger content where the
previous correction was overly aggressive.
Change-Id: I30b026b5f4535e9601e3178d738066459d19c8fb
Resolved two TODO items.
Force a minimum value of 1.0 for frame duration as per section duration.
Column inactive zone is currently set to 0 as most of the serious issues
relating to inactive regions relate to letter boxing.
Change-Id: Ifbab3acf2c089d7305620a7ff7ed7c3536cc9235
In Aq mode 1 the segment and AQ delta for each block is based
on spatial variance. There may be a net imbalance between blocks
that have lower Q than the baseline value and those that have higher Q.
This patch monitors that imbalance and extends the allowed baseline
Q range for the frame to accommodate adjustment of that baseline value
to compensate.
Change-Id: Iae8a48c7c01fe2af94a141e149d03acf467237ca
