> This is always somthing I have wanted to do for video stream
> processing, writeing a limited proceedural language which can be
> refactored as a dataflow graph for efficent implementation (of video
> processing).

This sounds a lot like how GStreamer operates. An example from the
gst-launch manpage:

  gst-launch filesrc location=music.mp3 ! mad ! audioconvert ! vorbisenc !  oggmux ! filesink location=music.ogg

I'm not sure they've done as much work on a procedural language, but
they have a good set of 'plugins', as they call them.