Patent ID: 6927803

Claim:
A video mixing apparatus taking out a foreground object component from a source video signal obtained by shooting an object in front of a monochromatic screen, and fitting the object component into a background video signal, said apparatus comprising: a key signal generator for setting a key signal distribution formed by a first oval body surrounding a reference color of the screen in a three-dimensional color space and a second oval body surrounding the first oval body, and for generating a mixing key signal according to a positional relation among the source video signal, the first oval body and the second oval body in the key signal distribution; and a mixing processor for taking out the foreground object component by the mixing key signal, and for mixing the object component with the background signal; and a screen signal generator for generating a screen signal by using the source video signal and the screen reference color, the screen signal indicating a screen component included in the source video signal, wherein said key signal generator generates the mixing key signal by using the source video signal and the screen reference color, and said mixing processor subtracts the screen signal from the source video signal based on the mixing key signal to obtain the foreground object component and the foreground object component is mixed with the background video signal based on the mixing key signal; and wherein said screen signal generator outputs (i) the source video signal as the screen signal when the source video signal is inside the first oval body, and (ii) a coordinates value as the screen signal when the source video signal is outside the first oval body, where the coordinates is a cross point of the first oval body and a vector starting from the screen reference color toward the source video signal.