Superimposition
From Wikipedia, the free encyclopedia
Superimposition is a graphics term meaning the placement of an image on top of an already-existing image, usually to add to the overall image effect, but also sometimes to conceal something (such as when a different face is superimposed over the original face in a photograph)
This technique is used to produce photomaps by superimposing aerial photographs over grid lines, contours and other normal mapping features.


