ffmpeg: fix memleak and corruption of AVSubtitle with multiple outputs

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/bitstream: document the double volatile

Suggested-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/libtwolame: fix encoding lsf with defaults

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avfilter: add hqx filter (hq2x, hq3x, hq4x)

Partially fixes Ticket #3404 (xbr filter remaining)
Do not show libzvbi in the configure output if it was not enabled.

It is already shown in the list of external libraries if it was enabled.
Show duration for large asf files as written in the file header.

Fixes ticket #3428.
avformat/flvdec: give live_flvdec a separate name

This should fix a infinite loop on freebsd

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>