This is necessary to preserve the quality information currently exported
with coded_frame. Add the new side data to every encoder that needs it,
and use it in avconv.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Fix warning from clang "absolute value function 'abs' given an argument
of type 'long long' but has parameter of type 'int' which may cause
truncation of value [-Wabsolute-value]".
It makes more sense to print the timebase exactly as it is set. Also,
this avoids a divide by zero when av_dump_format() is called on a format
context before writing the header.
