| 摘要 |
PROBLEM TO BE SOLVED: To prevent the deterioration of image quality, even though antialiasing processing is applied to both image and key signals by applying the antialiasing processing, using only the pixels that include no background color of a foreground image with respect to the pixels whose colors con possibly be mixed subjecting to an arithmetic operation of an image filter circuit. SOLUTION: When a foreground image and a background image are consisted together by means of a key signal, an image filter circuit 3 applies the antialiasing processing to the foreground image to reduce aliasing noises which appear at a graphic boundary. Meanwhile, a key filter circuit 5 applies the antialiasing processing to the key signal. A pixel detection circuit 6 detects the pixels whose colors may possibly be mixed through an arithmetic operation of the circuit 3, based on the key signal and the size of the circuit 3. Then the circuit 3 applies the antialiasing processing using only the pixels which does not contain background colors of the foreground image to the pixels which are detected by the circuit 6 and whose colors may possibly be mixed. |
