| 摘要 |
PURPOSE:To realize a copy guard, by recording the inherent discrimination code of a recorder and reproducing device and controlling the propriety of reproducing digital signals in accordance with the reproduction of the code when input digital signals have a specific sampling frequency. CONSTITUTION:When it is discriminated that input digital signals through a change-over switch S1 and digital signal processing circuit 10 have a specific sampling frequency, a microcomputer 15 reads out the discrimination code corresponding to the number of the digital audio tape recorder (DAT) stored in a ROM 16 and stores the code in a sub-code memory 13. At the same time, the sampling frequency at the time of recording is set to a specific frequency and the discrimination code is also written on a tape. Then the muting off or muting on by the computer 15 is controlled whether or not the reproduced discrimination code coincides with the discrimination code of the DAT and the reproduction can be executed by means of the DAT used for the recording only. Therefore, copying of a tape can be inhibited by using other DATs, and thus, a copy guard is realized. |
