US Patent 7925054 Motion detection apparatus

A motion detection apparatus which extracts a 1-frame differential signal from a video signal, separates the 1-frame differential signal into a vertical low frequency signal having a frequency which is lower than a predetermined frequency with respect to the vertical direction of a frame of the video signal and a vertical high frequency signal having a frequency which is equal to or higher than the predetermined frequency, separates, from the vertical low frequency signal and the vertical high frequency signal, signals having different frequency bands with respect to the horizontal direction of a frame of the video signal, respectively, and combines these separated signals.