change background in cheese webcam

[Jorge Luis Vazquez <jlvazquez825 gmail com>]

hello guys, is there a way to change the background of a video taken 
with cheese and my webcam. I've looked all over the net, but can't find 
a solution that doesn't involved using covering the background with some 
sheet or something. In other words I'm looking for something that can do 
this at the software level. I wonder if cheese has something for this.

Thanks