Motion detection circuit and a noise suppression circuit including the same

Abstract

An interframe difference signal is generated from the video signal and its one-frame delayed video signal. A filter removes a carrier color signal from the interframe difference signal to output the interframe difference luminance signal. A first motion judging circuit judges a motion in the video signal at a target pixel from the interframe difference luminance signal to output a first motion judging result in accordance with a first edge detection signal. A second motion judging circuit judges a motion in the video signal at the target pixel from a luminance signal and the carrier signal in the interframe difference signal to output a second motion judging result in accordance with a second edge detection circuit. The first and second motion judging results are combined. A majority determining circuit determines majority of the combined result from adjacent Q pixels in accordance with a third edge detection signal. A circular signal generation circuit generates a coefficient K according to the result of the majority determining circuit. The interframe difference signal is multiplied with k to generate a circulation signal. A subtractor subtracts the circulation signal from the video signal to generate an output video signal of which noise is suppressed.