advice on live capture to disk

[John Bazik]

> gst-launch-1.0 -e\
>        decklinksrc mode=17 connection=1 name=raw\
>        raw.videosrc ! queue !\
>                videorate ! video/x-raw,framerate=30/1 !\
>                videoconvert !\
>                x264enc speed-preset=medium ref=4 quantizer=20 !\
>                queue ! mux.\
>        raw.audiosrc ! queue ! audioconvert ! audio/x-raw,format=S16LE !\
>                voaacenc ! queue ! mux.\
>        qtmux name=mux !\
>                filesink location=/var/tmp/live$$.mov
> 
> My source is 720p, UYVY, 60000/1001fps.  Gstreamer version is 1.2.4.
> 
> Speed-presets slower than medium drop frames.  The warnings come
> from decklinksrc.  This looks good, but in a large white field (a
> whiteboard), I see an irregular mosaic pattern emerge, grey-on-white,
> and start to ripple, then it clears and starts over, continuously.
> Cycles about every 8 seconds (240 frames).

Any thoughts on this pipeline?  Does my description of the artifacts sound like something I should be able to fix?

John