| 摘要 |
PURPOSE:To reduce the influence of the leakage of a luminance signal and a chrominance signal to mutual channel at an area where an image changes remarkably and to reduce dot disturbance, by using a luminance signal/chrominance signal separation filter appropriately based on the correlation of a composite video signal in a vertical and a horizontal directions. CONSTITUTION:A composite color TV signal supplied to an input terminal 1 is sampled at an A/D converter 4. And in the sampled signal, a sample value at a remarked sampling point and the sample values at the sampling points at a picture one line above and one line under are extracted simultaneously by passing through delay circuits 5a and 5b. And extracted sample values are supplied to a vertical direction chrominance signal extraction filter 6a, a horizontal direction chrominance signal extraction filter 6b, a horizontal and vertical direction chrominance signal extraction filter 6c, and an image correlation decision circuit 7. The decision circuit 7 detects the correlation of the image with respect to the remarked sample point in the vertical and horizontal directions, and a switch circuit 8 is switched so that the output of the filter 6a can be selected when the correlation in the vertical direction is large especially, and the output of the filter 6b can be selected when correlation in the horizontal direction is large, and the output of the filter 6c can be selected in other cases.
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