[mythtv] ffmpeg sync

[Janne Grunau]

Hi,

the next ffmpeg sync is overdue and working H.264 PAFF (since 9th of 
october) in ffmpeg is an exellent opportunity.

Almost 2000 revisions passed since the last merge and noteable changes 
beside PAFF are the updated ac3 decoder, dca decoder and slice-based 
parallelism in the H.264 decoder.
With both H.264 changes playback of H.264 HDTV as used in Europe should 
be possible on most dual core processors. A 15mbit 1080p stream plays 
on a Athlon64 X2 2ghz with using between 50 and 70% cpu.

There are tons of other changes (ape and atrac3 decoder, nut and 
matroska muxer, much cleanup and file splitting, ...) but those aren't 
that relevant to mythtv.

The patch compiles cleanly on x86 and x86_64. Mpeg2 and H.264 recordings 
seems be without regressions. Plugins compiled fine but aren't tested.

Please test and report any problems. Patches apply with -p2.

http://www.grunau.be/ffmpeg_sync_10712_14666_0.diff.bz2

simple multithreaded patch, threading must be enabled 
with --enable-ffmpeg-pthreads.
http://www.grunau.be/0001-enable-multithreaded-video-stream-decoding.patch


I still have some things to do before the patch can be applied:
test plugins, especially dvd playback
merge libavformat/mpegts.c many conflicts, is still r8742 plus our 
modifications
review configure changes
test ppc altivec build

Janne