| 摘要 |
PURPOSE:To prevent effect of interference of a chrominance signal by providing a prescribed synchronizing relation between the sampling period and a color burst signal included in a composite picture signal in extracting a monochroic picture signal from a color composite signal. CONSTITUTION:A digital color composite picture signal Vd of a receiver 1 is given to a bus L. An OSC section 16 consists of a PLL to generate a sampling clock fs of an A/D converter 12. The frequency of a clock fs is set sufficiently higher than the maximum frequency of a color composite picture signal Va. The OSC section uses a PLL to apply phase lock to the period of the clock fs to one over an integer of the period of the color burst signal B. The sampling circuit 21 of the picture recorder 2 samples the signal Vd by using a sampling clock fs/m having a comparatively longer period. A 1/m frequency division circuit 25 frequency-divides the frequency of the clock fs of the receiver 1 to one over m (integer) to generate a clock fs/m. Thus, the clock fs/m has always a prescribed synchronizing relation to the signal B.
|
