| 摘要 |
A noise reduction circuit for use in a video signal recording and/or reproducing apparatus for eliminating noise components from an input luminance signal comprises a high pass filter circuit for extracting a high frequency signal component from the input luminance signal, a first limiter circuit for limiting the high frequency signal component at a first limiting level, a multiplier circuit for determining the degree of preemphasis and/or deemphasis by multiplying a predetermined coefficient to the limited signal, summing and subtracting circuits respectively for adding and subtracting the output signal of the first amplifying means to and from the input luminance signal, and a feedback loop for feeding back the output signal of the high pass filter circuit to its input port. The feedback loop comprises a second multiplier circuit which modifies the amplitude of the signal passing therethrough by a second level which is set substantially higher than the first level of the first limiter circuit.
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