Paul Davis wrote: > On Tue, 2009-01-27 at 13:49 +0100, Olivier Guilyardi wrote: > >> For example, in FFmpeg, each audio and video packets are tagged using a PTS >> which is computed using av_gettime() which calls gettimeofday(). > > this should be considered a bug and reported as such to the FFmpeg group > (preferably with a patch to make it use clock_gettime() if available). > gettimeofday is a non-linear, non-mononotic clock if ntp is used. it is > not suitable for timestamping in this way. without ntp, it will work > better, but it is still subject to potential non-monotonicity.
I just wanted to let you know that an interesting discussion is going on the ffmpeg-devel mailing list, about choosing a time source, NTP effects, and A/V synchronization. It is named "libavdevice: PTS stability and risks of drift". -- Olivier _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
