Method for suppressing noise in image signals and an image signal processing device adopting such a noise suppression method

摘要

In an image signal processing device, a subtractor circuit 4 and an absolute value calculating circuit 6 calculate the absolute value of the difference between the image signal of the previous frame fed from a frame memory 1 and the image signal of the current frame, and a subtractor circuit 5 and an absolute value calculating circuit 7 calculate the absolute value of the difference between the image signal of the previous-previous frame fed from a frame memory 2 and the image signal of the previous frame. An adder circuit 8 adds together the thus calculated absolute values of the differences between those image signals to calculate the degree of motion, on the basis of which a gain setting circuit 9 sets a gain. The output from the subtractor circuit 4 is multiplied by this gain to generate a noise component.