DEVICE FOR IMPROVING PICTURE QUALITY OF HIGH GRADE TELEVISION

摘要

PURPOSE:To reduce the capacity of memories within a signal processing circuit by reducing the sampling frequency of a chrominance signal to a quarter of the case of a luminance signal, A/D converting it and passing it through a quadruple rate conversion digital filter after the signal is processed. CONSTITUTION:An analog luminance signal Y is digitized at an A/D converter 12a by a sampling frequency fs through an LPF 11a and after a flare correction and an outline correction are applied to it at a signal processing circuit 13a, it is supplied to a digital matrix circuit 14. On the other hand, a wide frequency band chrominance component Cw and a narrow frequency band chrominance component Cn are supplied to A/D converters 12b and 12c respectively through an LPF 11b and an LPF 11c. Each converter samples an inputted chrominance component with the frequency of a quarter of the sampling frequency in the luminance signal and digitizes it and outputs it to signal processing parts 13b and 13c respectively. The signals that the flare correction and the outline correc tion are applied at the signal processing part are outputted to a matrix circuit 14 through digital filters 17 and 18 with the quadruple rate.