Hi list,
at a general-culture class I gave about digital effects for stage performances, 3 or 4 people asked about how to switch from live video to pre-recorded video seamlessly. The context is in shadow theater, so we're only dealing with contours/outlines/shapes.
The basic setup is that the shadow seen by the audience is in fact a live video projection of the real shadow, captured with infrared lighting and infrared camera. This permits "video scratching" of the shadow, so it can detach from the actor/puppet, lag behind and then catch up the movements of the actor/puppet. This works pretty well, but at the moment I only have a vvvv implementation, not a pd one.
The idea is to add a means to transition into pre-recorded video, such as, say, the shadow of bird flewing away.
I imagine such a setup with the following steps :
- capture the actor's shadow
- vectorise the outline of the shadow
- build paths to the target outline (the bird)
- stretch the actor's outline towards the bird's outline.
I guess there are some tools in opencv or some other lib for vectorisation or outline detection.
Maybe it's easier to have some flood-fill algorithm to progressively fill the gaps between the two outline.
I'd really like to build such a tool, because there's somewhat high demand on that.
So the question is : what process makes senses, what libraries/objets should I use to build such a tool ?
Any suggestions are welcome.
Cheers,
Charlot