Digital color control and chroma killer device

摘要

An automatic color control and chroma killer circuit 3 and video processing system is provided that is capable of controlling an amplitude of a color signal and of performing a killer function with a simple construction without using a divider and/or vertical filter. The ACC/ACK device includes ACC and ACK circuitry which may be selectively enabled with operating signals to a selector 27. When the selector 27 enables amplitude detector 25, the amplitude detector 25 detects amplitude of the input color signal and a coefficient controller 26 compares it with a killer level. If the input color signal fails to meet the killer level then the coefficient controller 26 controls a coefficient generated by the coefficient generator 22 to perform a killer operation. The ACC operation and circuitry is thereby ACK controlled until an input color signal meets or exceeds the killer level. When the selector 27 enables the multiplier circuit 11 according to an operating signal input, the input color signal is ACC controlled by the multiplier circuit 11, and amplitude detector 21, a coefficient generator 22, a coefficient memory 23 and a delay circuit 24.