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.
Results with 8x8 dct are about 0.3% worse.
Change-Id: I00100cdc96e32deced591985785ef0d06f325e44
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.
Change-Id: I08e8cba978f2bbf3019f8413f376b8e2cd85eba4
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.
Change-Id: I3d48d5800468d655191933894df6b46e15adca56
This is to fix a decoder crash when decoder skips a number of frame to
continue decoding from a later key frame.
Change-Id: I3ba116eba6c3440e0528a21f53745f694302e4ad
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.
Change-Id: Id10c94dccd45f58e5310bacfdf6ee63cbb60b86f
Mode selection for SBs could enter an infinite loop because
the interpolation filter mode index was not being reset
correctly.
Change-Id: I4bbe726f29ef5b6836e94884067c46084713cc11
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.
Change-Id: I6a7e7ced8f27e120fafb99db2dc9c6293f8d20f7
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.
Change-Id: I2aac6f81ee0ae9e03d6a8da4f8681d69b79ce41f
Various fixups to resolve issues when building vp9-preview under the more stringent
checks placed on the experimental branch.
Change-Id: I21749de83552e1e75c799003f849e6a0f1a35b07
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.
Change-Id: Ie708b54d8e1898af742846ce2d1e2b0d89fd4ad5
This patch changes the token packing to call the bool encoder API rather
than inlining it into the token packing function, and similarly removes
a special get_signed case from the detokenizer. This allows easier
experimentation with changing the bool coder as a whole.
Change-Id: I52c3625bbe4960b68cfb873b0e39ade0c82f9e91
For coefficients, use int16_t (instead of short); for pixel values in
16-bit intermediates, use uint16_t (instead of unsigned short); for all
others, use uint8_t (instead of unsigned char).
Change-Id: I3619cd9abf106c3742eccc2e2f5e89a62774f7da
In some cases intra modes in inter frames give
an over smoothed appearance. Especially with
noisy but flat content.
Also in some cases there were problems with key
frame sizing again with very flat but noisy content.
These are temporary changes to help alleviate the
visual problems but will almost certainly hurt metric
results especially at the very low data rate end.
Change-Id: I11549179a19277ffc283d9788bc70168f2a8bdc9
This is to fix a decoder crash when decoder skips a number of frame to
continue decoding from a later key frame.
Change-Id: I3ba116eba6c3440e0528a21f53745f694302e4ad
The mismatch was caused by an improper merge of cleanup code around
tokenize_b() and stuff_b() with TX32X32 experiment.
Change-Id: I225ae62f015983751f017386548d9c988c30664c
Modifies the scanning pattern and uses a floating point 16x16
dct implementation for now to handle scaling better.
Also experiments are in progress with 2/6 and 9/7 wavelets.
Results have improved to within ~0.25% of 32x32 dct for std-hd
and about 0.03% for derf. This difference can probably be bridged by
re-optimizing the entropy stats for these transforms. Currently
the stats used are common between 32x32 dct and dwt/dct.
Experiments are in progress with various scan pattern - wavelet
combinations.
Ideally the subbands should be tokenized separately, and an
experiment will be condcuted next on that.
Change-Id: Ia9cbfc2d63cb7a47e562b2cd9341caf962bcc110
Gives 0.5-0.6% improvement on derf and stdhd, and 1.1% on hd. The
old tables basically derive from times that we had only 4x4 or
only 4x4 and 8x8 DCTs.
Note that some values are filled with 128, because e.g. ADST ever
only occurs as Y-with-DC, as does 32x32; 16x16 ever only occurs
as Y-with-DC or as UV (as complement of 32x32 Y); and 8x8 Y2 ever
only has 4 coefficients max. If preferred, I can add values of
other tables in their place (e.g. use 4x4 2nd order high-frequency
probabilities for 8x8 2nd order), so that they make at least some
sense if we ever implement a larger 2nd order transform for the
8x8 DCT (etc.), please let me know
Change-Id: I917db356f2aff8865f528eb873c56ef43aa5ce22
As suggested by Yaowu, we can use eob to reduce the complexity
of the vp9_ihtllm_c function. For the 1080p test clip used, the decoder
performance improved by 17%.
Change-Id: I32486f2f06f9b8f60467d2a574209aa3a3daa435
Add a function clip_pixel() to clip a pixel value to the [0,255] range
of allowed values, and use this where-ever appropriate (e.g. prediction,
reconstruction). Likewise, consistently use the recently added function
clip_prob(), which calculates a binary probability in the [1,255] range.
If possible, try to use get_prob() or its sister get_binary_prob() to
calculate binary probabilities, for consistency.
Since in some places, this means that binary probability calculations
are changed (we use {255,256}*count0/(total) in a range of places,
and all of these are now changed to use 256*count0+(total>>1)/total),
this changes the encoding result, so this patch warrants some extensive
testing.
Change-Id: Ibeeff8d886496839b8e0c0ace9ccc552351f7628
