Question about framegrabbing/video effect chains ..

[Zachris Trolin]

Hello list. 

I'm new to QT and would like some pointers of how and what can be done in the way of video manipulation. 

I'm very interested in how to grab frames, or perform manipulation on framedata using QT and preferable phonon (although any other suggestion is welcome). 
 
I would like to give it a try to implement a VJ:ing application, I have used pd, keyworx, grid etc, and they all have some problems. 

The very first step would be to implement a variable rate videoplayer, but soon after comes frame manipulation: preferably done in QT  (something like the composition demo, but with videostreams. ). 

Any suggestions?