| 摘要 |
<p>PURPOSE:To simplify the circuit and to make the circuit advantageous to the circuit integration by combining a delay circuit, a code inversion circuit and a selector so as to constitute modulation and demodulation circuit of a color signal. CONSTITUTION:A delay circuit 4 retarding a digital color signal digitized by a frequency being a multiple of 4N of a chrominance subcarrier by one clock time, sign inversion circuits 5, 6 inverting sign of a signal not retarded and a retarded signal respectively and selectors 7, 8 selecting a specific data from in total 4 kinds of digital color signals obtained from the former circuits and outputting the result constitute a demodulation circuit, from which a color difference signal is obtained. Then sign inversion circuits 12, 13 inverting the sign of the color difference signal and a selector 14 selecting a specific data from the signal not subject to sign inversion and the inverted signal and outputting the result constitute a modulation circuit to obtain an original chrominance carrier signal. Thus, the circuit scale is reduced and a digital color signal processing circuit suitable for circuit integration is obtained.</p> |
