In the start_frame() debug log, print the reference pos value rather than the evaluated value converted to int.
That's required because -1 is evaluated as NAN, which converted backto int looks like a random number, this is especially annoying whendebugging sources with undefined pos (as the video4linux2 device)....
Use hierarchic names convention (prefix them with av_expr) for theeval API.
More grep-friendly and more consistent with the rest of the FFmpegAPI.
Originally committed as revision 25708 to svn://svn.ffmpeg.org/ffmpeg/trunk
Add setpts filter, ported from the libavfilter soc repo.
Originally committed as revision 25655 to svn://svn.ffmpeg.org/ffmpeg/trunk