DIGITAL VIDEO SIGNAL PROCESSING METHOD AND DEVICE

PROBLEM TO BE SOLVED: To suppress a false signal which wraps around to a frequency band lower than fs/2, without the need for oversampling that results in increasing the power consumption by applying nonlinear processing to three primary color signals R, G, B from a color television camera 21. SOLUTION: R, G, B signals are fed to a 1st digital filter 22, which shifts a phase of the R, B signals and a phase of the G signal by half a pixel. The resulting signals are given to a gamma correction circuit 23, a knee circuit 24, and a clip circuit 24, where digital nonlinear processing is applied to the signals, the resulting signals are fed to a 2nd digital filter 26, in which the phases of the three primary color signals are arranged and a matrix circuit 27 produces a luminance signal Y. The phases of the spurious signals resulting from harmonic components caused by the nonlinear processing and wrapped around to a frequency band of the fs/2 or lower produced in the R, B signals and the B signal are inverted by 180 degrees with each other. Since the mixing ratio of the R, B signals and the G signal is about 0.5:0.5, the false signals arisen in the luminance signal Y are cancelled with each other.