This commit introduces a chessboard pattern search for the prediction
filter type search. It runs extensive search in alternate blocks and
allows the rest blocks to refer coding decisions of their nearby
neighbors.
For pedestrian 1080p at 4000 kbps, the runtime of speed -5 goes down
from 43990 ms to 42200 ms. The overall compression performance for
RTC set is changed by -1.37%.
Change-Id: Icfe220c49451cda796f0ca91d935c9ed01e56c9d
Calculate the difference variance between last source frame and
current source frame. The variance is calculated at 16x16 block
level. The variances are compared to several thresholds to decide
final partition sizes.
An adaptive strategy is implemented to decide using
SOURCE_VAR_BASED_PARTITION or FIXED_PARTITION based on motions
in the video. The switching test is done once every
search_type_check_frequency frames.
The selection of source_var_thresh needs to be investigated
further later.
RTC set Borg test showed 0.424% overall psnr gain, and 0.357%
ssim gain. For clips with large enough static area, the
encoding speedup is around 2% to 15%.
Change-Id: Id7d268f1d8cbca7fb8026aa4a53b3c77459dc156
Copy up to a certain bsize, otherwise set to a fixed bsize.
This helsp to reduce artifact near moving boundary caused by full partition
copy without checking motion of super-block.
This artifact can occur at speeds 3,4 in real-time mode.
Issue: https://code.google.com/p/webm/issues/detail?id=738.
Change-Id: I05812521fd38816a467f72eb6a951cae4c227931
This commit reduces the frequency of frames using finer quantizer
in non-RD coding flow, and slightly tune up the quantizer resolution
when used. It provides 1.7% compression gains in speed -5 at no speed
difference.
Change-Id: I430249a51260a841a0402666e5ec1566e4f7d5a6
The new tolerance is a little higher than before (especially
for kf/gf/arf) so this change gives an encode speed up
for some clips up for speeds 0-2.
Change-Id: I63f7d6c9cc11c7f58742f41e250dcd3eab1741eb
