Audio grabbing part is commented out and untested.
 The syntax is like that:
  v4l:<device>[:option=value:...]
 options: channel,norm (pal, ntsc,secam), frequency (not really there is
          a factor), audio, size (WxH or subqcif,qsif,qcif,sif,cif,vga),
          codec (optional, mpeg1 or mpeg4 and need to have compiled the
          encoders modules)
 ex: v4l:/dev/video:channel=0:frequency=8052:norm=secam:size=vga
 Please test.
 * rawvideo.c: a pseudo decoder for raw video (I420).
 * packetizer/*, mux/*, stream_output.c: fixed (I hope) audio/video
synchro problems.