In the variance calculations the difference is summed and later squared.
When the sum exceeds sqrt(2^31) the value is treated as a negative when
it is shifted which gives incorrect results.
To fix this we cast the result of the multiplication as unsigned.
The alternative fix is to shift sum down by 4 before multiplying.
However that will reduce precision.
For 16x16 blocks the maximum sum is 65280 and sqrt(2^31) is 46340 (and
change).
PPC change is untested.
Change-Id: I1bad27ea0720067def6d71a6da5f789508cec265
Merged in most of the current common prediction changes
that were under the #if CONFIG_COMPRED option.
Change-Id: If4e6f61dbe7b86dd449f6effbe93b5eb7e893885
Further changes to make experiments with the context
used for coding the dual pred flag easier.
Current best performing method tested on derf is a two
element context based on reference frame. I also tried
various combinations of mode and reference frame as
shown in commented out case using up to 6 contexts.
Derf +0.26 overall psnr +0.15% ssim vs original method.
Change-Id: I64c21ddec0abbb27feaaeaa1da2e9f164ebaca03
Further use of common prediction functions and experiments
with alternate contexts based on mode and reference frame.
For the Derf set using reference frame as basis of context
gives +0.18% Overall Psnr and +0.08 SSIM
Change-Id: Ie7eb76f329f74c9c698614f01ece31de0b6bfc9e
We should only change the dual prediction mode if we actually entered
the recode branch. Else, it may potentially undo beneficial changes
to the dual prediction mode in the first encode iteration.
Change-Id: I79fc53e5fd0bb551092ed422c797619f1566f002
Some conditions were conditional under a threshold, whereas they should
always execute. Also, some conditions were testing an array instead of
the values within it.
Change-Id: Ia6892945cfbbe07322e6af6be42cd864bf9479c1
Allow the application to change the frame size during encoding. This
is only supported when not using lagged compress.
Change-Id: I89b585d703d5fd728a9e3dedf997f1b595d0db0f
The existing code updated the reference frame probabilities before
the test to evaluate the impact of using updated probabilities
in vp8_estimate_entropy_savings().
The estimate of cost and savings is still basic and does not reflect
the new prediction code but this would require per MB costings
and the benefit is probably marginal, as this is really just used for
rate estimation in the loop.
Change-Id: Id6ba88ae6e11c273b3159deff70980363ccd8ea1
This commit merges the NEWNEAR experiment such that it
is effectively always on.
The fact that there were changes in the threading code again
highlights the need to strip out such features during the
bitstream development phase as trying to maintain this code
(especially as it is not being tested) slows the development cycle.
Change-Id: I8b34950a1333231ced9928aa11cd6d6459984b65
Initial modifications to make limited use of common prediction
functions.
The only functional change thus far is that updates to the probabilities are
no longer "damped". This was a testing convenience but in fact seems to
help by a little over 0.1% over the derf set.
Change-Id: I8b82907d9d6b6a4a075728b60b31ce93392a5f2e
Trial of a modified prediction function that ranks each possible
reference frame based on a combination of local usage and
frame level probability. The code is a bit cleaner and simpler.
In direct comparison with old unpredicted method with segment level
coding turned off for mode,ref & EOB the prediction gives a gain on derf
of around 0.4%. There is some further gain from bug fixes over earlier code.
With segment coding on the prediction method is slightly -ve on some very
easy clips (at low rates) due to slightly higher overheads, but better on harder
clips. Overall neutral on derf in direct comparison on latest code base, but
compared to earlier code without bug fixes about +0.7% overall psnr
+0.3% SSIM.
Change-Id: I5b8474658b208134d352d24f6517f25795490789
Sometimes, a user doesn't have enough bandwidth to send high-resolution
(i.e. HD) video even though the camera catches HD video. This change
allowed users to skip highest-resolution encoding by setting that level's
target bit rate to 0.
To test it, modify the following line in vp8_multi_resolution_encoder.c.
unsigned int target_bitrate[NUM_ENCODERS]={1400, 500, 100};
To skip the highest-resolution level, change it to
unsigned int target_bitrate[NUM_ENCODERS]={0, 500, 100};
To skip the first and second highest resolution levels, change it to
unsigned int target_bitrate[NUM_ENCODERS]={0, 0, 100};
This change also fixed a small problem in mapping, which slightly helped
quality and performance.
Change-Id: I977bae9a9fbfba85c8be4bd5af01539f2b84bc81
Extended prediction and coding of reference frame where
a subset of options are flagged as available at the segment level.
Updated copyright notices.
Switch to SAD in mbgraph code as SATD problematic for the
foreground and background separation as it can ignore large DC shifts.
Change-Id: I661dbbb2f94f3ec0f96bb928c1655e5e415a7de1
As a precursor to encoding 32x32 blocks this cl adds the
ability to encode the frame superblock (=32x32 block) at
a time. Within a SB the 4 indiviual MBs are encoded in
raster-order (NW,NE,SW,SE).
This functionality is added as an experiment which can be
enabled by ispecifying --enable-superblocks in the
command line specified to configure (CONFIG_SUPERBLOCKS
macro in the code).
To make this work I had to disable the two intra
prediction modes that use data from the top-right of the
MB.
On the tests that I have run the results produce
almost exactly the same PSNRs & SSIMs with a very
slightly higher average data rate (and slightly higher
data rate than just disabling the two intra modes in
the original code).
NOTE: This will also break the multi-threaded code.
This replaces the abandoned change:
Iebebe0d1a50ce8c15c79862c537b765a2f67e162
Change-Id: I1bc1a00f236abc1a373c7210d756e25f970fcad8
Commented out changes from earlier checking:
"Change Iab7f1eff: vpnext use segref segmentation filter"
Which in its current state breaks the decoder.
Change-Id: I9185098aeda8ce65310f338c4c9375f4a39005d3
This check in uses the common prediction interface functions
to code reference frame.
Some updates made regarding the impact of the new code in rd loop
but there remain TODOs in this regard.
Change-Id: I9da3ed5dfdaa489e0903ab33258b0767a585567f
This does not change any functionality just modifies the code to
use the common prediction module interface for coding
the segment data.
Change-Id: Ifd43e9153573365619774a4f5572215e44fb5aa3
This is the final commit in the series converting to the new RTCD
system. It removes the encoder csystemdependent files and the remaining
global function pointers that didn't conform to the old RTCD system.
Change-Id: I9649706f1bb89f0cbf431ab0e3e7552d37be4d8e
This commit continues the process of converting to the new RTCD
system. It removes the last of the VP8_ENCODER_RTCD struct references.
Change-Id: I2a44f52d7cccf5177e1ca98a028ead570d045395
This is a proof of concept RTCD implementation to replace the current
system of nested includes, prototypes, INVOKE macros, etc. Currently
only the decoder specific functions are implemented in the new system.
Additional functions will be added in subsequent commits.
Overview:
RTCD "functions" are implemented as either a global function pointer
or a macro (when only one eligible specialization available).
Functions which have RTCD specializations are listed using a simple
DSL identifying the function's base name, its prototype, and the
architecture extensions that specializations are available for.
Advantages over the old system:
- No INVOKE macros. A call to an RTCD function looks like an ordinary
function call.
- No need to pass vtables around.
- If there is only one eligible function to call, the function is
called directly, rather than indirecting through a function pointer.
- Supports the notion of "required" extensions, so in combination with
the above, on x86_64 if the best function available is sse2 or lower
it will be called directly, since all x86_64 platforms implement
sse2.
- Elides all references to functions which will never be called, which
could reduce binary size. For example if sse2 is required and there
are both mmx and sse2 implementations of a certain function, the
code will have no link time references to the mmx code.
- Significantly easier to add a new function, just one file to edit.
Disadvantages:
- Requires global writable data (though this is not a new requirement)
- 1 new generated source file.
Change-Id: Iae6edab65315f79c168485c96872641c5aa09d55
Picks a per segment loopfilter. Adapts the algorithm to search for
a loopfilter value for each separate segment. Further todo fix the
bias
Improvements .06 % ov psnr, .11% ssim
http://www.corp.google.com/~jimbankoski/no_crawl/segmentedpicklpf.html
Change-Id: Ic6a571c16fcd6ec0139f4de1f8061f87c6515a10
changed the token cost for 8x8 transformed macroblock used in trellisquant
from those derived from 4x4 transform coefficient distribution to those
derived from 8x8 transform coefficient distribution. Test results show
this fix help 8x8 transform based compression consistently on cif and hd
sets:
http://www.corp.google.com/~yaowu/no_crawl/t8x8/cif_cost8x8only.html
(avg psnr:.14% glb psnr: .17% ssim: .20%)
http://www.corp.google.com/~yaowu/no_crawl/t8x8/hd_cost8x8only.html
(avg psnr:.17% glb psnr: .18% ssim: .58%)
Note: To test the effect of this change, 8x8 transform was forced to be used
only on 16x16 predicted macroblocks on inter frames, the effect would be
bigger had all macroblocks been forcd to use 8x8 transform.
Change-Id: If9b7868b75357c66541f511e5ee78e4d2d4929a4
using an 8-tap filter.
The results with 3 different 8-tap filters on the derf set are in:
http://www.corp.google.com/~debargha/vp8_results/enhinterp.html
The one that gives the most gain achieves an overall gain of about
0.6%. The results for a set of 12 hd (720p) videos are in:
http://www.corp.google.com/~debargha/vp8_results/enhinterp_hd.html
with max gain of 0.55% with the same filter. The best filter apparently
achieves the best trade-off between pass band ripple and stop band
attenuation.
Change-Id: I919e28ae245c0493147fa0864f8c9d048a9dd530
Commit e06c242ba introduced a change to call vp8_find_near_mvs() only
once instead of once per reference frame by observing that the only
effect that the frame had was on the bias applied to the motion
vector. By keeping track of the sign_bias value, the mv to use could
be flip-flopped by multiplying its components by -1.
This behavior was subtley wrong in the case when clamping was applied
to the motion vectors found by vp8_find_near_mvs(). A motion vector
could be in-bounds with one sign bias, but out of bounds after
inverting the sign, or vice versa. The clamping must match that done
by the decoder.
This change modifies vp8_find_near_mvs() to remove the clamping from
that function. The vp8_pick_inter_mode() and vp8_rd_pick_inter_mode()
functions instead track the correctly clamped values for both bias
values, switching between them by simple assignment. The common
clamping and inversion code is in vp8_find_near_mvs_bias()
Change-Id: I17e1a348d1643497eca0be232e2fbe2acf8478e1
This commit is incomplete, as it does not synchronize the loop filter
before returning a handle to the reconstructed frame in
vpx_codec_get_preview_frame(), which can cause (false?) failures
when running the test_reconstruct_buffer test.
This may be related to a bug that does cause visible artifacts, which
is also under investigation.
This reverts commit 380d64ecb19984a1466e727244a41445ae919060.
Change-Id: Iad710941e7731d44fc2bde63bc63d6763cc4629e
