Chromakey device

Abstract

Abstract PURPOSE:To prevent the deterioration of an S/N, and besides, to prevent the generation of blue fringe by obtaining a key signal by considering relevance between the direction and the quantity of change in color space corresponding to the change of a position and color coordinate of a back color in respect of the color corrdinate of the optional point of a foreground picture. CONSTITUTION:R, G, B signals are sent to color change detection circuits 12R, 12G, 12B and 13R, 13G, 13B, and the R, G, B components of a color change vector corresponding to the change of the position in a horizontal direction (X axis direction) and a vertical direction (Y axis direction) are detected. Color change speeds are calculated by vector absolute value output circuits 15, 18 and weighting variable output circuits 16,19 respectively, and are sent to multipliers 17,20, and each relational speed Sx, Sy in the directions of X axis and Y axis is calculated. On the other hand, each normalized relational speed in X axis and Y axis from circuit parts 21, 22 is inputted to data converters 23, 24, and is made into the key signals Kx, Ky, and they are multiplied by the multiplier 25, and the key signal Kxy is obtained. Thus, by obtaining the key signal in accordance with the relational speed, the back color and a subject can be discriminated from each other, and the deterioration of the S/N can be reduced.

Inventors

• 👤 Jiyon Debitsudo Roora Robaato
• 👤 ロバート・ジョン・デビッド・ローラ

Bibliographic Details