| 摘要 |
PURPOSE:To digitize a signal processing system and to reduce the power consumption by separating a color saturation degree component and a hue component from a chrominance signal and executing the signal processing and A/D conversion. CONSTITUTION:A color saturation degree component is A/D converted 105 and passed through an ACC circuit 106 to obtain a color saturation degree digital code signal E. In terms of a hue component, a chrominance signal is amplitude- limited 107 to take out only the hue component. The phase of the hue digital signal is compared with that of a reference subcarrier signal from an APC circuit 108 is compared 109, and these signals are subjected to the DC level conversion through an LPF. The DC level is A/D converted 111 to obtain a color difference digital code signal D. After the signals D and E are arithmetic-processed, a normal color difference digital code signal is outputted from a color difference signal amplitude correcting circuit for correcting a color difference level with the aid of the color saturation degree. Thus a signal processing system is made a digital circuit and the power consumption can be reduced accordingly. |
