[x264-devel] x264 Development Newsletter: Vol 22

[Jason Garrett-Glaser]

This is the twenty-second x264 development newsletter. This is a
regular email containing updates on fixes and improvements in the most
recent x264 push, along with updates on what's coming next.  Previous
versions can be found in the mailing list archives.

Fixes:

Yet another 4:4:4 chroma weightp bugfix.

Expand borders before chroma weightp analysis to avoid reading
uninitialized data.

Fix initialization of chroma planes in weightp analysis if U
early-terminates but V doesn't.

Fix zeroing of predictors in B-skip blocks.

Fix pic_out to be correctly formatted for 4:4:4 mode.

Avoid intermediate 4:2:0 conversions with 4:4:4 encoding when the
input to x264CLI is YUVJ*.

Fix invalid memory accesses in x86 lowres_init when width <= 16.

Fix a typo in p8x8 RD analysis.

Improvements:

Avoid some unnecessary allocations when B-frames and CABAC are disabled.

Shut up some Valgrind false-positives.

Use proper _flat SSE2 functions instead of AVX non-flat dequant
functions where appropriate; slightly faster.

Optimize predict_8x8_filter and eliminate a valgrind false-positive.

Scale interlaced refs/mvs for MVR predictors.  Should improve
compression marginally and fix a Valgrind error.  x264 should now be
reasonably Valgrind-clean.

Faster intra SATD x86 asm.

Add Hurd support to configure.

Upcoming:

--device and automatic --level restriction support is in the works, as
part of Google Code-In.  The patch is done, but needs review and adoption.

Automatic range handling (full vs TV) is in the works.

A per-option help system is in the works, as part of Google Code-In.
The patch is done, but needs editing of the help entries.

x262 is under development: a best-in-class MPEG-2 encoder built using
the x264 framework.  Both P and B-frames are done and working.

Google Summer of Code is in progress: Trellis ME and H.264/MVC support
are the two projects.

SOCIS is in progress, with work on more ARM assembly code in progress.

4:2:2 support is coming soon, both to x264 and libavcodec.

Jason Garrett-Glaser

The x264 Team