| 摘要 |
PURPOSE:To attain the color demodulation without uneven hue by using an output of a voltage controlled oscillator as a clock signal so as to sample a composite video signal, frequency-dividing the output of the voltage controlled oscillator into 1/N and applying the synchronizing detection and demodulation by a reference subcarrier set by a signal being the result of detection of a burst signal in a sampled composite video signal. CONSTITUTION:A burst signal is extracted from a composite video signal inputted via an input terminal 21 by a burst gate 22, a clock signal is generated in a phase locked loop comprising the burst gate 22, a phase detector 23, an integration circuit 24, a VCO 25 and a 1/N frequency-division counter 26, and the clock signal is obtained from the output of the VCO 25. On the other hand, a composite video signal inputted via the input terminal 21 is digitized by the A/D converter 27 and processed. A data in a line memory/frame memory 28 is read, the data of the same line and frame is used to apply digital processing and video processing so as to apply the video processing such as the repetition of same line and same frame.
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