| 摘要 |
PURPOSE:To set surely a numeral corresponding to a pedestal level with good response by comparing a PCM video signal after quantization with the set pedestal level and feeding back its PCM error signal. CONSTITUTION:A video signal from an input terminal 1 is fed to a differential amplifier 3 and a synchronizing separator circuit 4 via a buffer amplifier 2. An output signal of the differential amplifier 3 is converted into a PCM video signal by an A/D converter 5 and given to a subtractor circuit 6 and a luminance separating circuit 7. The luminance signal separated by the luminance separation circuit 7 is given to a latch circuit 8, where a PCM pedestal level signal is latched, and a pedestal potential is subtracted by a subtraction circuit 10 and a PCM error signal is outputted. The PCM error signal is given to the subtraction circuit 6 and fed back to the differential amplifier 3 via a D/A converter 11.
|
