Method and apparatus for processing a signal consisting of an object evolving on a coloured background

摘要

The method involves calculating a key which is used to separate the colours representing the image video source into three zones. The first zone defines the background colour, the second zone the subject and the third the transition zone between the background and the subject. The subject image is removed from an existing background and added to a new background using a mixing operation. The mixing operation is performed using a predefined formula where VD=KD*(video subject)-(1-KD)*video background, where KD is the decoupling key and VD is the total new background and subject image. The algorithm allows decolourisation of the subject transition zone on command (DZ) after which processing (9) of the subject on the new background is performed to produce the new video colour output.