You're reading my mind but how would I do that.Get the picture on the blanket.
actually, you don't put anything on the blanket. The blanket just provides a solid background. Once you have that, most video software can swap everything that is a solid color with other video.
Exactly how its done depends on the software. I have video pad... if I get a chance I'll see if I can figure out how that works... (but I bet you beat me to it)
