| 摘要 |
PURPOSE:To completely restore a blanking signal by providing a comparing means which compares a digital picture signal and a reference signal indicating the blanking level with each other and an error correcting means which detects and corrects the error of the blanking level included in the output of the comparing means. CONSTITUTION:A reference signal N having the same value N as blanking level data multiplexed in picture data 42 is inputted to a comparator 1. When picture data 42 and the blanking level N coincide with each other as the result of comparison, an output signal 46 of the level N is generated and is supplied to a flip flop F/F 2 to set it to the high level, and a blanking signal 43 to a counter 3 and a picture processing device is outputted. The counter 3 is counted up by a clock signal 45 only when the blanking signal 43 is in the high level. Width M of the blanking period is preliminarily set by a reference signal M, and carry is generated at arrival at M after the start of counting and is outputted to an inverter 4, and the F/F 2 and the counter 3 are cleared by a reset signal 47. |
