Motion detector for chrominance signal in TV receiver

摘要

A motion detector for a chrominance signal which is used with a TV receiver equipped with a video signal motion detector. This motion detector for a chrominance signal has a delay element for delaying the chrominance signal of a video signal by 1 frame period, a subtracter for subtracting the output signal of the delay element from the input signal thereof, an absolute value conversion circuit to which the output signal from the subtracter is inputted, and a smoother circuit to which the output signal from the absolute value conversion circuit is supplied. If the chrominance signal of video signals on two consecutive frames are the same, the output signal of the subtracter becomes zero. If the chrominance signals of video signals on two consecutive frames are different, the output signal of the subtracter takes a positive or negative value. The negative value signal is converted into a positive value signal by the absolute value conversion circuit. A signal is outputted from the smoother circuit only when the chrominance signals of video signals on two consecutive frames are different. This outputted signal is a chrominance signal motion detection signal. The luminance signal contained in a video signal is removed from the video signal using a comb-type filter.