| 摘要 |
PURPOSE:To obtain stable reproduced pictures with a system where video data is written in a memory with a conversion-enable signal synchronizing with the vertical synchronism of a picture signal, by correcting a big shift of the horizontal synchronism if it is within a fixed time error. CONSTITUTION:An FF11 obtains the synchronization between a horizontal synchronizing signal H separated from a picture signal and a conversion-enable signal CON-ENA. The output of this synchronization is applied to gates 14A and 14B via an FF12. Then timing signals TA and TB of a timing generating circuit 13 are selected by circuits 14A and 14B and sent to an FF15. The signal CON- ENA is delivered from the FF15. In this case, the relation between signals H and CON-ENA is reduced at a time point of a detection clock T-CLK when the signal H is gradually accelerated and the time error between the signals H and CON-ENA is increased. As a result, a horizontal synchronizing part has no dropout and therefore stable reproduced pictures can be obtained. |
