You could possibly get screen captures over time back from the video card, though I do not know the specific API calls needed to accomplish it, and they may not be accessible to Java. This would mean you'd need a DLL making the calls written in C/C++ with a JNI wrapper.

Also just fyi... video games don't stream actual video to the video card, only geometry, textures and shaders. The video card takes this limited amount of information and turns the rendering process into a highly parallel process that's very fast, it would be nearly impossible to get the same frame-rate/quality on an equivalently powerful CPU with the current x86/64 architecture.

Anyways, I would love to know if capturing frames from the video card with processing is possible as well, if there are any experts out there who know a way, I'd be appreciative as well!

Jack