3D video and device mediation with GStreamer

Neat! Is there any support for allowing "effects" plugins to run in the pipeline? i.e. I want to take my real webcam, munge the audio/video, and present the result as another webcam stream. More specifically, I want to crop and zoom the output from my webcam so Skype sees the cropped result... (or perhaps run deepdream on my video feed to make the scrum meetings more interesting).

-ben