[x264-devel] x264 Development Newsletter: Vol 13

[Jason Garrett-Glaser]

This is the thirteenth x264 development newsletter.  If you missed the
first twelve, 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:

Fix some inline asm syntax that wasn't supported by LLVM's assembler.
Doesn't affect output on anything other than LLVM.

Fix a buffer overflow in the MP4 muxer with large frames.

Fix restoring of console title on Windows when ffms indexing is used.

Improvements:

Support Intel's compiler (ICC) on all x86 platforms.  In addition,
patch Intel CPU dispatcher to work properly on AMD systems.  Intel's
compiler intentionally cripples AMD CPUs -- this counteracts that
crippling.

Recognize Cygwin as a possible target and fix thread support on it.
Mingw (-mno-cygwin) is still the default on cygwin platforms though.

Altivec mc_weight and merged mb_cmp implementations.

New asm function: optimize_chroma_dc, with SSE2/SSSE3/SSE4/AVX
implementations on x86.

Eliminate the possibility of level_code overflow in the case of very
low QP and CAVLC + profile below High.  If a CAVLC level_code overflow
occurs, re-encode the macroblock with higher QPs until it goes away.

Upcoming:

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

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.

Adaptive MBAFF development is **done** -- it's now going through
cleanup and final optimizations.

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

Work is planned to integrate x264 with the Sandy Bridge's encoding
ASIC for improved encoding performance.  Current status is: waiting on
Intel (these guys move at the speed of an obese one-legged paraplegic
three-toed sloth swimming down a stagnant river of frozen helium while
chained to an osmium anchor stuck inside a black hole).

Jason Garrett-Glaser

The x264 Team