Noise processing system for a television receiver

In a television receiver which detects a composite video signal having a blank level and a gray level, and which includes a path for processing sync information derived from the composite video signal and another path for processing video information derived from the composite video signal, a noise processing system for reducing impulse noise in the sync processing path and in the video processing path, comprising:

• a first impulse detector receiving the composite video signal for detecting noise pulses which extend beyond a selected video noise threshold and for generating a control signal upon the occurrence of each such detection;
• first switch means receiving a gray level signal and a blank level signal, responsive to the receiver being in a blanking interval for outputting the blank level signal, and responsive to the receiver being in a non-blanking interval for outputting the gray level signal;
• second switch means receiving the composite video signal and the output of said first switch means, and being responsive to said control signal for replacing noise pulses in the composite video signal with the output of said first switch means, thereby generating a noise-processed video signal for application to the video processing path;
• and
• means receiving the composite video signal for eliminating therefrom noise pulses which exceed a selected sync noise threshold so as to generate another noise-processed video signal for application to the sync processing path.

In a television receiver which detects a composite video signal having a blank level and a gray level, and which includes a path for processing video information derived from the composite video signal, a noise processing system for reducing impulse noise in the video processing path, comprising:

• an impulse detector receiving the composite video signal for detecting noise pulses which extend beyond a selected video noise threshold and for generating a control signal upon the occurrence of each such detection;
• first switch means receiving a gray level signal and a blank level signal, responsive to the receiver being in a blanking interval for outputting the blank level signal, and responsive to the receiver being in a non-blanking interval for outputting the gray level signal;
• and
• second switch means receiving the composite video signal and the output of said first switch means, and being responsive to said control signal for replacing noise pulses in the composite video signal with the output of said first switch means, thereby generating a noise-processed video signal for application to the video processing path.