We had a client request a video chroma key processor for his theater. He wants it so his grandkids can put on a show in front of a green screen on stage and put images or video in the background. There seems to be several software options but a hardware based unit seems simpler since he is not real techy. Google found an sd unit that will do composite and svideo for under $400. I also found pro grade units from panasonic that do hd via dvi or sdi in the $10k-$30k range. I've seen cameras with the chroma key feature but not sure how they get new backgrounds. He also requested recording which I suggested pc recording or stand alone DVD burner. Has anyone done this and can make recommendations?