These functions are now used by the encoder.
This is WIP with the goal of creating a common idct/add for
the encoder and decoder. A boost of 1.8% was seen for
the HD rt test clip used.
[Tero] Added needed changes to ARM side.
Change-Id: Ibbb8000be09034203d7adffc457d3c3f8b06a5bf
Patch set 2: 64 bit build fix
Patch set 3: 64 bit crash fix
[Tero]
Patch set 4: Updated ARMv6 and NEON assembly.
Added also minor NEON optimizations to subtract
functions.
Patch set 5: x86 stride bug fix
Change-Id: I1fcca93e90c89b89ddc204e1c18f208682675c15
Call the idct/add after the tokenize. This is WIP with
the goal of creating a common idct/add for the encoder and
decoder. This move is necessary because the decoder's version
of the idct clobbers qcoeff, which is used by the tokenize.
Change-Id: I6b08d8e8397cd873647fa4fb9469884e3c876756
Changed 'int eob' to 'char *eob' in BLOCKD so that both encoder and
decoder will use eobs[25] array from MACROBLOCKD structure. In future,
this will enable use of the decoder side IDCT in the encoder.
Change-Id: I6e1c011628cb8864fd4a0b80f0279ce16a5ca978
It is discovered that in rare situations the 2nd order block may
produce a few small magnitude coefficients that has no effect on
reconstruction. The situations are a combination of low quantizer
values (high quality) and low energy in residual signals (content
dependent). This commit added code to detect such cases and reset
the 2nd order block to all 0.
Patch 1 to 4 used code to do all-zero-check on idct result buffer,
and tests on derf set showed a consistent gain of .12%-.14% on all
metrics.But due to a recent change Ie31d90b, the idct result buffer
is not longer populated. So patch 5&6 use an alternative method to
detect the situations. Tests on derf set now shows a consistent
quality gain of .16%-.20%.
As suggested by Jim, Patch 7&8 removed the condition of all first
order block not having any coefficient, instead we reset 2nd order
coefficients to all 0 if sum of absolute value of the coefficients
is small. So it does slightly more than just detecting the oddity
as discussed above, but tests on derf set now show a consistent
gain of .20%-.23% on all metrics.
It is worth noting here that this change does not have any effect
on mid/high quantizer range, it only affects the quantizer value
18 or blow. Within this range, the change helps compression by up
to 2.5% on clips in the derf set.
Change-Id: I718e19cf59a4fc2462cb7070832759beb9f7e7dd
Instead of using the predict buffer, the decoder now writes
the predictor into the recon buffer. For blocks with eob=0,
unnecessary idcts can be eliminated. This gave a performance
boost of ~1.8% for the HD clips used.
Tero: Added needed changes to ARM side and scheduled some
assembly code to prevent interlocks.
Patch Set 6: Merged (I1bcdca7a95aacc3a181b9faa6b10e3a71ee24df3)
into this commit because of similarities in the idct
functions.
Patch Set 7: EC bug fix.
Change-Id: Ie31d90b5d3522e1108163f2ac491e455e3f955e6
for SPLITMV and B_PRED modes. Modified code to use the bmi
found in mode_info_context instead of BLOCKD. On the decode
side, the uvmvs are calculated only when required, instead of
every macroblock. This is WIP. (bmi should eventually be
removed from BLOCKD)
Small performance gains noticed for RT encodes and decodes.(VGA)
Change-Id: I2ed7f0fd5ca733655df684aa82da575c77a973e7
I got this idea from Pascal (Thanks). Before encoding a macroblock,
copy it to a 16x16 buffer, and then read source data from there
instead. This will help keep the source data in cache, and help
with the performance.
Change-Id: Id05f4cb601299150511d59dcba0ae62c49b5b757
Code cleanup. The build inter predictor functions are
redundantly checking the mode_info_context for either
INTRA_FRAME or SPLITMV.
Change-Id: I4d58c3a5192a4c2cec5c24ab1caf608bf13aebfb
A large number of functions were defined with external linkage, even
though they were only used from within one file. This patch changes
their linkage to static and removes the vp8_ prefix from their names,
which should make it more obvious to the reader that the function is
contained within the current translation unit. Functions that were
not referenced were removed.
These symbols were identified by:
$ nm -A libvpx.a | sort -k3 | uniq -c -f2 | grep ' [A-Z] ' \
| sort | grep '^ *1 '
Change-Id: I59609f58ab65312012c047036ae1e0634f795779
This patch adds a weighting factor on RDMULT for UV blocks. The change
has an overall gain about 0.5% based on ssim, between 0.1 and 0.2% by
psnr numbers.
Change-Id: I97781b077ce3bb7e34241b03268491917e8d1d72
This intends to correct the tendency that VP8 aggressively favors rate
on intra coded frames. Experiments tested different numbers in [0, 1]
and found 9/16 overall provided about 2-4% gains for all-intra coded
clips based on vpx-ssim metric. The impact on regular encoded clips
is much smaller but positive overall. Overall impact on psnr is also
positive even though very small.
Change-Id: If808553aaaa87fdd44691f9787820ac9856d9f8a
ARM NEON has a platform specific version of vp8_recon16x16mb, though
it's just a stub to extract the various parameters from the
MACROBLOCKD struct and pass them to vp8_recon16x16mb_neon(). Using
that function's prototype directly will be a better long term solution,
but it's quite an invasive change.
Change-Id: I04273149e2ade34749e2d09e7edb0c396e1dd620
Most of the code that actually uses these matrices indexes them as
if they were a single contiguous array, and coverity produces
reports about the resulting accesses that overflow the static
bounds of the first row.
This is perfectly legal in C, but converting them to actual [16]
arrays should eliminate the report, and removes a good deal of
extraneous indexing and address operators from the code.
Change-Id: Ibda479e2232b3e51f9edf3b355b8640520fdbf23
when a subsequent frame is encoded as an alt reference frame, it is
unlikely that any mb in current frame will be used as reference for
future frames, so we can enable quantization optimization even when
the RD constant is slightly rate-biased. The change has an overall
benefit between 0.1% to 0.2% bit savings on the test sets based on
vpxssim scores.
Change-Id: I9aa7bc5cd573ea84e3ee655d2834c18c4460ceea
This patch moves the scattered updates to the mb skip state
(mode_info_context->mbmi.mb_skip_coeff) to vp8_tokenize_mb. Recent
changes to the quantizer exposed a bug where if a macroblock
could be coded as a skip but isn't, the encoder would run the
loopfilter but the decoder wouldn't, causing a reference buffer
mismatch.
The loopfilter is controlled by a flag called dc_diff. The decoder
looks at the number of decoded coefficients when setting this flag.
The encoder sets this flag based on the skip state, since any
skippable macroblock should be transmitted as a skip. The coefficient
optimization pass (vp8_optimize_b()) could change the coefficients
such that a block that was not a skip becomes one. The encoder was
not updating the skip state in this situation for intra coded blocks.
The underlying issue predates it, but this bug was recently triggered
by enabling trellis quantization on the Y2 block in commit dcd29e3,
and by changing the quantizer range control in commit 305be4e.
Change-Id: I5cce5da0dbc2d22f7d79ee48149f01e868a64802
This uses MB variance to change the RDO weight for mode decision
and quantization.
Activity is normalized against the average for the frame, which is
currently tracked using feed-forward statistics.
This could also be used to adjust the quantizer for the entire
frame, but that requires more extensive rate control changes.
This does not yet attempt to adapt the quantizer within the frame,
but the signaling cost means that will likely only be useful at
very high rates.
Change-Id: I26cd7c755cac3ff33cfe0688b1da50b2b87b9c93
Experimented with different value for Y2_RD_MULT ranging f[1, 32],
without adapting the value to MB coding mode/frame type/Q value,
4 works out best among all values, providing overall 0.1% coding
gain on the test set.
Change-Id: I6b2583a8aa5db5e7e5c65c646301909c0c58f876
Changes 'The VP8 project' to 'The WebM project', for consistency
with other webmproject.org repositories.
Fixes issue #97.
Change-Id: I37c13ed5fbdb9d334ceef71c6350e9febed9bbba
The main reason for the change was to reduce cycles in the token
decoder. (~1.5% gain for 32 bit) This layout should be more
cache friendly.
As a result of this change, the encoder had to be updated.
Change-Id: Id5e804169d8889da0378b3a519ac04dabd28c837
Note: dixie uses a similar layout
These copies occurred for each macroblock in the encoder and decoder.
Thetemp MB_MODE_INFO mbmi was removed from MACROBLOCKD. As a result,
a large number compile errors had to be fixed.
Change-Id: I4cf0ffae3ce244f6db04a4c217d52dd256382cf3
Replace the exponential search for optimal rounding during
quantization with a linear Viterbi trellis and enable it
by default when using --best.
Right now this operates on top of the output of the adaptive
zero-bin quantizer in vp8_regular_quantize_b() and gives a small
gain.
It can be tested as a replacement for that quantizer by
enabling the call to vp8_strict_quantize_b(), which uses
normal rounding and no zero bin offset.
Ultimately, the quantizer will have to become a function of lambda
in order to take advantage of activity masking, since there is
limited ability to change the quantization factor itself.
However, currently vp8_strict_quantize_b() plus the trellis
quantizer (which is lambda-dependent) loses to
vp8_regular_quantize_b() alone (which is not) on my test clip.
Patch Set 3:
Fix an issue related to the cost evaluation of successor
states when a coefficient is reduced to zero. With this
issue fixed, now the trellis search almost exactly matches
the exponential search.
Patch Set 2:
Overall, the goal of this patch set is to make "trellis"
search to produce encodings that match the exponential
search version. There are three main differences between
Patch Set 2 and 1:
a. Patch set 1 did not properly account for the scale of
2nd order error, so patch set 2 disable it all together
for 2nd blocks.
b. Patch set 1 was not consistent on when to enable the
the quantization optimization. Patch set 2 restore the
condition to be consistent.
c. Patch set 1 checks quantized level L-1, and L for any
input coefficient was quantized to L. Patch set 2 limits
the candidate coefficient to those that were rounded up
to L. It is worth noting here that a strategy to check
L and L+1 for coefficients that were truncated down to L
might work.
(a and b get trellis quant to basically match the exponential
search on all mid/low rate encodings on cif set, without
a, b, trellis quant can hurt the psnr by 0.2 to .3db at
200kbps for some cif clips)
(c gets trellis quant to match the exponential search
to match at Q0 encoding, without c, trellis quant can be
1.5 to 2db lower for encodings with fixed Q at 0 on most
derf cif clips)
Change-Id: Ib1a043b665d75fbf00cb0257b7c18e90eebab95e
The new fdct lowers the round trip sum squared error for a
4x4 block ~0.12. or ~0.008/pixel. For reference, the old
matrix multiply version has average round trip error 1.46
for a 4x4 block.
Thanks to "derf" for his suggestions and references.
Change-Id: I5559d1e81d333b319404ab16b336b739f87afc79
When the license headers were updated, they accidentally contained
trailing whitespace, so unfortunately we have to touch all the files
again.
Change-Id: I236c05fade06589e417179c0444cb39b09e4200d
