What is Keying ?
Keying is the use of a particular colour to act as the matte of one layer.
What is Matte?
Matte is a technique that utilises two or more images to combine them into one final image. This technique is often used in fimmaking to combine a foreground image like an actor on a set in front of a green or blue screen with a backgroun image or a completely CGI generated set.
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