[FFmpeg-user] Bad A/V Sync Using ffmpeg on V4L2 Input Device

Leo L. Schwab ewhac at ewhac.org
Tue Mar 25 09:32:04 CET 2014

LANGLOIS Olivier PIS wrote:
> Notice the start times of each input. For alsa, it uses abs time and by
> default, webcam uses monotonic time. Something that I was about to try and
> perhaps you try it out to see if it helps is to use ts abs for the v4l2
> input.
	As illustrated in my response to Lou's message, adding '-ts abs' to
the command line doesn't help; I still see the sync issue.

> However, it might not be enough. Check if your webcam is using the
> uvcvideo driver.  [ ... ]

	Nope.  This one uses the em28xx driver.


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