Apparatus for selectively dampening noises contained in Y signal for a video signal processing system

An apparatus for selectively dampening noises in luminance signals for a video signal processing system, comprising:

• level limiter means for limiting amplitude levels of the luminance signals received from an input terminal;
• noise dampening processor means connected to said level limiter means, for dampening the noises of the luminance signals as result from a transmission channel to provide processed luminance signals;
• buffer means for buffering the output luminance signals from said level limiter means to provide buffered luminance signals;
• switching means for enabling transmission of one of said processed luminance signals and said buffered luminance signals in dependence upon reception of a selected control signal;
• average detector means for detecting amplitude levels of the output luminance signals from said level limiter means to provide an average luminance value of said output luminance signals;
• comparator means for comparing said average luminance value to a reference value to provide a first control signal;
• first selector means for provide a second control signal selected by a user for controlling said switching means;
• and
• second selector means for making a selection between one of said first and second control signal to provide said selected control signal to control said switching means.

A video noise reduction circuit, comprising:

• means for receiving video signals from a transmission channel;
• level limiter means for removing high frequency components from said video signals to provide limited signals;
• noise dampening processor means for dampening noises of said limited signals resulted from said transmission channel to provide processed signals;
• buffer means for buffering said limited signals to provide buffered signals;
• switching means for enabling transmission of one of said processed signals and said buffered signals in dependence upon reception of a control signal;
• average detector means for determining amplitude levels of said limited signals to provide an average value;
• comparator means for comparing said average value of said limited signals to a reference value to provide a compared signal;
• and
• switch selector means for providing said control signal to operate said switching means in dependence upon reception of said compared signal and a command signal representative of a user's selected signal for enabling transmission of one of said processed signals and said buffered signals.