Is there a way to automatically cut/matte elements out of a video clip?

[Blake Turner]

Hi, I'm trying to figure out how to isolate elements in videos that I'm auto-rotoscoping. I'm not sure what forum I should look in or even how to phrase the question. Basically, I have some action videos (skateboarders etc.) that I want to cut out of their backgrounds to apply one effect to them, and another effect or color treatment to the background to get a better separation of foreground and background. I was hoping there would be an at least partially automated way to do this, so I wouldn't have to draw a bezier path by hand on each frame.