| 摘要 |
PURPOSE:To prevent picture re-recording, by performing a beat processing on the vertical synchronizing signal part of composite picture signals output from a picture apparatus. CONSTITUTION:Composite picture signals output from a picture apparatus are distributed and sent to a mixing circuit 6 and a vertical synchronizing separator circuit 3. Then, the separated vertical synchronizing signal is combined with oscillating signals which vary within a prescribed deviation width and sent from an oscillating circuit 4, at a vertical synchronizing signal processing circuit 5, and the combined signal is sent to the mixing circuit 6. At the mixing circuit 6, both inputs are mixed and a beat processing is performed on the vertical synchronizing signal part of the composite picture signal. This signal becomes a picture re-recording prevention processing composite picture signal and sent to a picture recording terminal 7. Magnetic picture recording tapes formed in this way can be used for reproducing, but cannot be used for picture re-recording because the vertical synchronizing signal makes racings at high speed in case of picture re-recording. |
