On 24 Jun 2013, at 15:17, Steve Cookson wrote: > I have a Dazzle DVC100 which outputs mpeg4, or so I understand. > > I use v4l2src to access it like this: > > gst-launch -e v4l2src device=/dev/video1 ! videorate ! video/x-raw-yuv If that pipeline works, then your source element is outputting raw video, not mpeg4.