This is the first patch for refactoring of the code related to
high-precision mv, so that 1/4 and 1/8 pel motion vectors can
co-exist in the same bit-stream by use of a frame level flag.
The current patch works fine for only use of 1/4th and
only use of 1/8th pel mv, but there are some issues with the
mode switching in between. Subsequent patches on this change Id
will fix the remaining issues.
Patch 2: Adds fixes to make sure that multiple mv precisions can
co-exist in the bit-stream. Frame level switching has been tested
to work correctly.
Patch 3: Fixes lines exceeding 80 char
Patch 4:
http://www.corp.google.com/~debargha/vp8_results/enhinterp.html
Results on derf after ssse3 bugfix, compared to everything
enabled but the 8-tap, 1/8-subpel and 1/16-subpel uv. Overall the
gains are about 3% now. Hopefully there are no more bugs lingering.
Apparently the sse3 bug affected the quartel subpel results more than
the eighth pel ones (which is understandabale because one bad predictor
due to the bug, matters less if there are a lot more subpel options
available as in the 1/8 subpel case).
The results in the 4th column correspond to the current settings.
The first two columns correspond to two settings of adaptive switching
of the 1/4 or 1/8 subpel mode based on initial Q estimate. These
do not work as good as just using 1/8 all the time yet.
Change-Id: I3ef392ad338329f4d68a85257a49f2b14f3af472
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
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
A problem can arise on static clips with force key frames where
attempts to avoid popping lead to a progressive reduction in key
frame Q that ultimately may lead to unexpected overspend against
the rate target.
The changes in this patch help to insure that in such clips the
quality of the key frames across the clip is more uniform (rather
than starting bad and getting better - especially at low target rates).
This patch also includes a fix that removes a delta on the Y2DC
when the baseline q index < 4 as this is no longer needed.
There is also a fix to try and prevent repeat single step Q adjustment in
the recode loop leading to lots of recodes, especially where the use
of forced skips as part of segmentation has made the impact of Q on
the number of bits generated much smaller.
Patch 2: Amend "last_boosted_qindex" calculation for arf overlay frames.
Change-Id: Ia1feeb79ed8ed014e4239994fcf5e58e68fd9459
update_mbgraph_frame_stats used xd->mode_info_context
before it had been setup, resulting in potentially
random accesses of uninitialized memory.
This fix allocates a local MODE_INFO structure to hold
the data generated in the function.
Change-Id: Ic9e75610008ce0e2d690e8e583c21582fee6fc45
Only encode sign bit for feature data that can have a sign.
Tweaks to the test segmentation rules so that it now actually gives
a net benefit on the derf set of about 0.4% though much higher
on some clips at the low end.
Change-Id: I8e61f1aebf41c9037db7e67e2f8975aa18a0c986
This quite large check in includes the following:
Merge in some code from Ronald (mbgraph.c) that scans a Gf/arf group.
This is used as a basis for a simple segmentation for the normal frames
in a gf/arf group. This code also uses satd functions from Yaowu.
Adds functionality for coding the latest possible position of an EOB for
blocks in the segment. (Currently 0-15 only, hence just for 4x4 dct).
Where the EOB position is 0 this acts like "skip" and the normal coding
of skip at the per mb level is disabled.
Added functions (seg_common.c) for setting and reading segment feature
elements. These may want to be optimized away at some point but while the
mecahnism is in a state of flux they provide a single location for making
changes and keep things a bit cleaner.
This is still proof of concept code. Currently the tested feature set:-
Quantizer,
Loop Filter level,
Reference frame,
Prediction Mode,
EOB end stop.
TBD:-
Add functions for setting and reading the feature data with range
and validity checking.
Handling of signed and unsigned feature data. At the moment all is assumed
to be signed and a sign bit is coded but many cannot be negative.
Correct handling of EOB feature with intra coded blocks.
Testing/trapping of legal/illegal ref frame and mode combinations.
Transform size switch plus merge and test with 8c8 DCT work
Merge and test with Sumans Segmenation coding optimizations
Change-Id: Iee12e83661c7abbd1e0ce6810915eb4ec35e2d8e
