Noise reduction circuit for a video signal

摘要

A noise reduction circuit for a video signal, comprises a feedback type comb filter in which an output video signal of a delay circuit which delays a video signal by one or two horizontal scanning periods, is fed back to an input side of the delay circuit through a feedback path, and an equalizer circuit coupled in series with the feedback type comb filter. The feedback path comprises a highpass or bandpass filter circuit and a coefficient multiplier which are coupled in series. The equalizer circuit has a frequency characteristic complementary to an envelope characteristic in a frequency characteristic of the feedback type comb filter.