Motion detecting circuit for video signal processor

A motion detecting circuit for a video signal processor, comprising:

• means for receiving a composite video signal having a low frequency band containing only a low frequency component of a luminance signal and a high frequency band containing both a high frequency component of the luminance signal and a chrominance signal superposed on the high frequency component of the luminance signal;
• filter means coupled to the receiving means for separating the video signal into the low and high frequency components;
• first detecting means coupled to the filter means for detecting a low frequency luminance motion component based on an inter-frame correlation of two successive frames of the low frequency component of the video signal;
• second detecting means coupled to the filter means for detecting a high frequency luminance motion component based on an inter-frame difference of two successive frames of the high frequency component of the video signal;
• third detecting means coupled to the filter means for detecting a chrominance motion signal based on an inter-frame correlation of two successive frames of the high frequency component of the video signal;
• first threshold means coupled to the first detecting means for generating a low band luminance motion digit signal when the low frequency luminance moving signal exceeds a first predetermined level;
• second threshold means coupled to the second detecting means for generating a low band luminance motion digit signal when the high frequency luminance moving signal exceeds a second predetermined level;
• control means coupled to the first and second threshold means for generating a control signal in response to the low and high band luminance motion digit signals;
• gate means coupled to the third detecting means and the control means for selectively transmitting therethrough the chrominance moving signal in response to the control signal;
• and
• selection means coupled to the first detecting means and the gate means for selectively outputting the one of the low frequency luminance moving signal and the chrominance moving signal having the high signal intensity.