| 摘要 |
PURPOSE:To improve S/N of an video signal without decreasing a vertical resolution by detecting the level of a chrominance signal and controlling the amplitude of such as an amplitude limiter fitted with a control terminal to increase or decrease in level in accordance with the magnitude of the detected output. CONSTITUTION:A luminance signal Y and a chrominance signal C are inputted to input terminals 1 and 11, respectively. The level of the chrominance signal C is detected as a signal A in an amplitude detection circuit 10. The signal A is inputted to a control terminal of an amplitude limit circuit 8. At the time of a high level of the signal A, said circuit 8 is controlled so that a limit amplitude level can be higher, whereas at the time of a lower level of the signal A, the control amplitude level is so controlled to become lower or zero. Thus the mixed modulation distortion caused by an included chrominance signal can be removed from the reproduced luminance signal only when the level of the reproduced luminance signal is lower, and the level of the chrominance signal is higher (namely, only when the mixed modulation distortion is large).
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