| 摘要 |
PROBLEM TO BE SOLVED: To obtain a YC separating device which reproduces video of high quality neither generating a longitudinal stripe pattern of a luminance signal nor exerting adverse effects on a signal level, the density of a color, etc., even if the image has its synchronism disordered or is an oblique-line, a solid color, or a raster image. SOLUTION: A linear YC separating circuit 31 uses a band-pass filter and a two-dimensional YC separating circuit 34 uses a comb-shaped filter. A subtracter 39 calculates vertical correlation according to vertical pixel information, a subtracter 40 calculates horizontal correlation according to horizontal pixel information, and a adder 41 adds a threshold K1, and then a comparator 42 outputs the vertical and horizontal correlation results as a signal C to a decision circuit 38. The decision circuit is supplied with the result of comparison with a vertical threshold K2 from a 2nd comparator circuit 36 and the result of comparison with a horizontal threshold K3 from a 3rd comparator circuit 37, and selects one of the output of the linear YC separating circuit and two-dimensional separating circuit 34 through its internal logic circuit.
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