avformat/wtvdec: demux mpeg2 extradata

Signed-off-by: Peter Ross <pross@xvid.org>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/wtvenc: pad judiciously when writing mpeg2 extradata

Padding rule described here http://msdn.microsoft.com/en-us/library/windows/desktop/dd390707(v=vs.85).aspx

Signed-off-by: Peter Ross <pross@xvid.org>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avutil/opt: dont crash on av_opt_set_dict() with NULL

This allows calling the function without the need to check if the
dictionary contains any entries

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/avio: also set generic URL context options

This should have no effect currently as there are no such options yet.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/mpegtsenc: move startcode validity check to ff_check_h264_startcode

Signed-off-by: Peter Ross <pross@xvid.org>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/wtvenc: advise user when H264 startcode is not present

Fixes ticket #3473.

Signed-off-by: Peter Ross <pross@xvid.org>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>