One Knob Picture Control

Abstract

Since the beginning of color television, a main concern has been over the complexity of customer controls. It is difficult for the average layman and even for most engineers to properly set the contrast, brightness and chroma controls for optimum picture quality. Attempts have been made to solve this problem but costs were high and the solution left much to be desired. With the advent of integrated circuits, the solution is in hand. This paper describes a monolithic integrated circuit wherein a single adjustment controls the contrast, chroma amplitude, and brightness level of the TV receiver. This control adjusts both luminance and chrominance amplitude simultaneously. DC restoration of the video signal to black level eliminates need to readjust the brightness control. The unique DC restoration function is performed in the I.C.