| 摘要 |
PROBLEM TO BE SOLVED: To generate a chrominance subcarrier whose phase is stable for color demodulation in the case of demodulating a color from a digital video composite signal. SOLUTION: A chrominance subcarrier generating circuit 6 gives 1st and 2nd chrominance subcarriers respectively to multipliers 4, 5, from which color difference signals R-Y, B-Y based on a digital modulation color signal C are demodulated. An integration circuit 11 integrates a burst period of the color difference signals R-Y, B-Y and integral values IR, IB are fed to a phase control circuit 9. The phase control circuit 9 compares the integral value IR with an absolute value of the integral value of other line having already been stored and whether a phase of the 1st and 2nd chrominance subcarriers for a video period in succession to the burst period is controlled by a control parameter setting a phase in one preceding line in response to the comparison result or controlled by a control parameter calculated from the integral value IR on one preceding line is selected.
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