Method and circuit for the white compression of a video signal

摘要

A method for the white compression of the components of a video signal which are above the standard level of approximately 100% is proposed, the threshold for compression being controlled in dependence on the video signal level exceeding the standard level. For this purpose, a pulse signal is in each case derived from the peak value û of the video signal outside the blanking intervals, which pulse signal is added to the video signal within the next blanking interval. After that, a voltage by means of which the knee circuit is controlled is derived by comparing the pulse signal amplitude with a 100% reference level.