| 摘要 |
PURPOSE:To prevent the mixture of a portion below the black level and a negative synchronizing signal at reproduction by clipping the portion of a video signal below the black level into the black level before the negative synchronizing signal is added in a device recording the video signal while adding the negative synchronizing signal newly. CONSTITUTION:The portion of a MUSE signal inputted below the black level is clipped into the black level by a clip circuit 1 and its output is subject to A/D conversion and the result is fed in to a memory 3 and a synchronization detection circuit 4. The circuit 4 detects a frame pulse and a positive synchronizing signal from the MUSE signal. A negative synchronizing generation circuit 7 consists of, e.g., a ROM, a digital data of the negative synchronizing signal written in advance in the ROM by a readout clock is read synchronously with the synchronizing information from the circuit 4 and the negative synchronizing signal to be inserted newly is generated. A readout output from the memory 3 and the output from the circuit 7 are switched synchronously with the said synchronizing information and the negative synchronizing signal is added newly to the MUSE signal subject to time axis compression at each 1H.
|
