Yaowu Xu [Wed, 30 Jan 2013 21:01:49 +0000 (13:01 -0800)]
A fix point implementation of 32x32 idct
This commit changes the 32x32 idct to use integer only. The algorithm
was taken directly from "A Fast Computational Algorithm for the
Discrete Cosine Tranform" by W. Chen, et al., which was published in
IEEE Transaction on Communication Vol. Com.-25 No. 9, 1977. The signal
flow graph in the original paper is for a 32 point forward dct, the
current implementation of inverse DCT was done by follow the graph in
reversed direction.
With this implementation, the 32 point inverse dct contains a 16 point
inverse dct in its even portion, similarly the 16 point idct further
contains 8 point and 4 point inverse dcts.
As of patch 4, encoding tests showed there is no compression loss when
compared against the floating point baseline. Numbers even showed very
small postives. (cif: .01%, std-hd: .05%).
Paul Wilkins [Thu, 24 Jan 2013 18:28:33 +0000 (18:28 +0000)]
Simplify Zero bin and zero bin run code.
Simplification to eliminate a number of very large data
data structures. All zero run, zbin boosts for different
transform sizes are now limited to a maximum run length
of 15 before they max out the boost.
Some further work still needs be done to refactor, rationalize
and optimize the multiple quantizer functions.
The simplification coupled with tweaks to the 16 element array
now used for all transform sizes, has minimal effect on quality.
Deb Mukherjee [Tue, 15 Jan 2013 14:43:35 +0000 (06:43 -0800)]
Adds an error-resilient mode with test
Adds an error-resilient mode where frames can be continued
to be decoded even when there are errors (due to network losses)
on a prior frame. Specifically, backward updates are turned off
and probabilities of various symbols are reset to defaults at
the beginning of each frame. Further, the last frame's mvs are
not used for the mv reference list, and the sorting of the
initial list based on search on previous frames is turned off
as well.
Also adds a test where an arbitrary set of frames are skipped
from decoding to simulate errors. The test verifies (1) that if
the error frames are droppable - i.e. frame buffer updates have
been turned off - there are no mismatch errors for the remaining
frames after the error frames; and (2) if the error-frames are non
droppable, there are not only no decoding errors but the mismatch
PSNR between the decoder's version of the post-error frames and the
encoder's version is at least 20 dB.
John Koleszar [Fri, 18 Jan 2013 19:51:12 +0000 (11:51 -0800)]
Support multiple codecs in test infrastructure
This commit starts to convert the tests to a system where the codec
to be used is provided by a factory object. Currently no tests are
instantiated for VP9 since they all fail for various reasons, but it
was verified that they're called and the correct codec is
instantiated.
John Koleszar [Tue, 22 Jan 2013 16:31:55 +0000 (08:31 -0800)]
Merge changes Ia82cef79,I7324a75a,I7b66daad,I73344451,I91dc210f,I5945b5ce into experimental
* changes:
Use alt-ref frame context for keyframes
Preserve the previous golden frame on golden updates
Generalize and increase frame coding contexts
Start to anonymize reference frames
Update encoder to use fb_idx_ref_cnt
Remove buffer-to-buffer copy logic
John Koleszar [Fri, 18 Jan 2013 22:35:20 +0000 (14:35 -0800)]
Use alt-ref frame context for keyframes
This matches the behavior prior to generalizing the frame context
selection, and intuitively makes sense in that the first forward ref
is immediately after the keyframe, so it's quality is improved a bit
by using the keyframe's entropy context rather than the default.
Yaowu Xu [Thu, 17 Jan 2013 21:26:24 +0000 (13:26 -0800)]
a minor change to a portion of loop filtering
The loop filtering used for MB edge or internal edge of a MB using 8x8
tranform was reading 5 pixel each side and writting 3 pixel each side.
With suggestion from Aki and Scott on hardware&software performance,
this commit changed to read 4 pixel each side and write 3 pixel each
side.
John Koleszar [Wed, 16 Jan 2013 20:19:42 +0000 (12:19 -0800)]
Preserve the previous golden frame on golden updates
This commit restores the quality lost when the buffer-to-buffer copy
logic was removed. Note that this is specific to the current use of
golden frames and will need rework when RTC functionality is added.
John Koleszar [Tue, 15 Jan 2013 23:57:11 +0000 (15:57 -0800)]
Generalize and increase frame coding contexts
Previously there were two frame coding contexts tracked, one for normal
frames and one for alt-ref frames. Generalize this by signalling the
context to use in the bitstream, rather than tieing it to the alt ref
refresh bit. Also increase the number of contexts available to 4, which
may be useful for temporal scalability.
John Koleszar [Tue, 15 Jan 2013 21:49:44 +0000 (13:49 -0800)]
Start to anonymize reference frames
Remove lst_fb_idx, gld_fb_idx, alt_fb_idx, refresh_last_frame,
refresh_golden_frame, refresh_alt_ref_frame from common. Gold/Alt are
encode side conventions. From the decoder's perspective, we want to be
dealing with numbered references.
Updates to active_ref 2 signal mode context switches, vestigial from
refresh_alt_ref_frame. This needs some clean up to make sense with
increased numbers of reference frames, as well as reimplementing the
swapping of alt/golden which was previously done using the
buffer-to-buffer copy mechanism removed in an earlier commit.
John Koleszar [Mon, 14 Jan 2013 22:44:39 +0000 (14:44 -0800)]
Remove buffer-to-buffer copy logic
This is the first in a series of commits to add additional reference
frames to the codec. Each frame will be able to update any of the
available references, but copying between references is not
supported.
John Koleszar [Mon, 14 Jan 2013 19:49:30 +0000 (11:49 -0800)]
Use INT64_MAX instead of LLONG_MAX
These variables have the type int64_t, not long long. long long could
be a larger type than 64 bits. Emulate INT64_MAX for older versions of
MSVC, and remove the unreferenced vpx_ports/vpxtypes.h
Yaowu Xu [Mon, 14 Jan 2013 17:28:35 +0000 (09:28 -0800)]
changed UV plane loop filtering for TX_8X8
In commit 9a1d73d, loop filtering was added for UV 4x4 boundaries
when TX_8X8 is used by a MB. This commit further refined the decision
to be based on the actual transform used for the UV planes. When
UV planes use 4x4 transform, i.e. when prediction mode used is either
I8X8_PRED or SPLITMV, UV planes are filtered on 4x4 boundaries, and no
filtering is applied on 4x4 block boundaries when UV planes use 8X8
transform.
Ronald S. Bultje [Mon, 14 Jan 2013 20:43:12 +0000 (12:43 -0800)]
Reset x->skip for each iteration in the RD loop.
This prevents ill-defined behaviour, such as setting x->skip for a mode
that is excluded because of frame-level flags (e.g. filter selection,
compound prediction selection), then not breaking out of the RD loop
because the mode is not allowed, but keeping the flag on. Whatever mode
is iterated through next in the RD loop will then carry this flag, and
all sort of bad stuff happens, such as x->skip being set on intra pred
modes.
Deb Mukherjee [Wed, 9 Jan 2013 14:26:54 +0000 (06:26 -0800)]
Further enhancements/fixes on dct/dwt hybrid txfm
Fixes some scaling issues. Adds an option to only compute the
dct on the low-low subband for 32x32 and 64x64 blocks using
only a single 16x16 dct after 1 and 2 wavelet decomposition
levels respectively. Also adds an option to use a 8x8 dct
as building block.
Currenlty with the 2/6 filter and with a single 16x16 dct on
the low low band, the reuslts compared to full 32x32 dct is
as follows:
derf: -0.15%
yt: -0.29%
std-hd: -0.18%
hd: -0.6%
These are my current recommended settings, since the 2/6 filter
is very simple.
Scott LaVarnway [Sat, 12 Jan 2013 01:11:04 +0000 (17:11 -0800)]
WIP: Added sse2 version of vp9_mb_lpf_horizontal_edge_w
and vp9_mb_lpf_vertical_edge_w_sse2. This was quickly done so we can
run some tests over the weekend. Future commits will optimize/refactor these
functions further.
The decoder performance improved by ~17% for the clip used.
Adrian Grange [Tue, 8 Jan 2013 22:14:01 +0000 (14:14 -0800)]
New prediction filter
This patch removes the old pred-filter experiment and replaces it
with one that is implemented using the switchable filter framework.
If the pred-filter experiment is enabled, three interopolation
filters are tested during mode selection; the standard 8-tap
interpolation filter, a sharp 8-tap filter and a (new) 8-tap
smoothing filter.
The 6-tap filter code has been preserved for now and if the
enable-6tap experiment is enabled (in addition to the pred-filter
experiment) the original 6-tap filter replaces the new 8-tap smooth
filter in the switchable mode.
The new experiment applies the prediction filter in cases of a
fractional-pel motion vector. Future patches will apply the filter
where the mv is pel-aligned and also to intra predicted blocks.
Deb Mukherjee [Tue, 8 Jan 2013 20:18:16 +0000 (12:18 -0800)]
Adds 64x64 hybrid dct/dwt transform
This is to add to the 64x64 transform experiment as an alternative to
a 64x64 DCT.
Two levels of wavelet decomposition is used on a 64x64 block, followed
by 16x16 DCT on the four lowest subbands. The highest three subbands
are left untransformed after the first level DWT.
Yaowu Xu [Wed, 19 Dec 2012 19:34:49 +0000 (11:34 -0800)]
minor loop filter refactoring and cleanup
This commit did a couple of minor cleanup/refactoring to prepare for
futher loop filter experiments. It merged y_only version of loop filter
function into the regular one, which makes sure that same logic is used
for functions for picking level and for actual loop filtering.
Paul Wilkins [Thu, 3 Jan 2013 15:14:36 +0000 (15:14 +0000)]
Further change to mv reference search.
This experimental change reorders the search so
that all possible references that match the target
reference frame are tested first and these in order
of distance from the current block. These will usually
be the highest scoring candidates.
If we do not find enough good candidates this way
we try non matching cases. These will usually be lower
scoring candidates.
The change in order together with breakouts when
we have found enough candidates should reduce
the computational cost and especially reduce the number
of sort operations.
Quality Results:
Std Hd +0.228%, Hd +0.074%, YT +0.046%, derf +0.137%
This effect is probably due to the fact that more distant
weak candidates are now less likely to get "promoted" over
near candidates even if they are repeated.
Adrian Grange [Thu, 20 Dec 2012 22:56:19 +0000 (14:56 -0800)]
New interpolation filter selection algorithm
Old Scheme:
When SWITCHABLE filter selection is enabled the encoder
evaluates the use of each interpolation filter type and
selects the best one to use at the MB level. A frame-
level flag can be set to force the use of a particular
filter type for all MBs in a frame if it is more efficient
to encode that way. The logic here involved a Q dependent
threshold that assumed that the second 8-tap filter was
a high-pass filter. However, this requires a trip around
the recode loop. If the frame-level flag indicates use
of a particular filter, the other filters are not
evaluated in the pick_mode loop.
New Scheme:
Each filter type is evaluated at the MB level and a record
of the best filter is kept, irrespective of what filter
is signaled at the frame-level. Once all MBs have been
encoded, a decision is made as to what frame-level mode
to set for the *next* frame. If one filter is used by 80%
or more of the MBs, then this filter is forced since it
is assumed that this will be more efficient if the
next frame has similar characteristics. i.e. there is a
one-frame lag between measuring the filter selection and
setting the frame-level mode to use.
Yaowu Xu [Thu, 3 Jan 2013 16:00:00 +0000 (08:00 -0800)]
Merge cost_coeffs_2x2() into cost_coeffs()
Remove special case function cost_coeffs_2x2() and change function
cost_coeffs() to handle 2nd order haar block as it is handle all
other block types already.
Yunqing Wang [Fri, 28 Dec 2012 00:04:44 +0000 (16:04 -0800)]
Skip finding best ref_mvs when the mode is ZEROMV
Read mode before calling vp9_find_best_ref_mvs(). If the mode is
ZEROMV, the best ref_mvs are not needed. Then, we can skip calling
vp9_find_best_ref_mvs().
Yunqing Wang [Thu, 27 Dec 2012 21:48:17 +0000 (13:48 -0800)]
Switch the order of calculating 2-D inverse transform
The 2-D inverse transform X = M1*Z*Transposed_M2 was calculated
in 2 steps from left to right:
1. Vertical transform: Y = M1*Z
2. Horizontal transform: X= Y*Transposed_M2
In SIMD, a transpose is needed in vertical transform.
Here, switched the calculation order to do it from right to left.
In this way, we could eliminate that transpose by writing the
intermediate results out to their transposed positions.
Deb Mukherjee [Tue, 27 Nov 2012 23:51:06 +0000 (15:51 -0800)]
New previous coef context experiment
Adds an experiment to derive the previous context of a coefficient
not just from the previous coefficient in the scan order but from a
combination of several neighboring coefficients previously encountered
in scan order. A precomputed table of neighbors for each location
for each scan type and block size is used. Currently 5 neighbors are
used.
Results are about 0.2% positive using a strategy where the max coef
magnitude from the 5 neigbors is used to derive the context.
projects / libvpx / log