A method for combining a first digital image and a second background digital image, both images including pixels having color values, wherein the first digital image includes both a foreground region having foreground color values and a key color region characterized by a key color, as well as a mixed...http://www.google.com.au/patents/US5937104?utm_source=gb-gplus-sharePatent US5937104 - Combining a first digital image and a second background digital image using a key color control signal and a spatial control signal
