DEVICE FOR REDUCING NOISE IN IMAGE SIGNAL

摘要

PROBLEM TO BE SOLVED: To provide a device for reducing noises by which the noise reduction quantity quickly approaches an optimally selected value with respect to each motion. SOLUTION: The device for reducing noises in an image signal transmits the image signal through a temporal recursive filter, a feedback factor of the temporal recursive filter is a function of a motion of an image expressed by the image signal and utilizes 1st and 2nd factors to form the feedback factor with respect to each current image, and the 1st or 2nd factor which is smaller substantially determines the feedback factor. The 1st factor is formed from the feedback factor of the preceding image and the 2nd factor is calculated from a difference between the preceding image and the current image.