RECORDING METHOD FOR SIGNAL, SIGNAL RECORDER, REPRODUCING METHOD FOR SIGNAL AND SIGNAL REPRODUCER

摘要

PURPOSE:To protect a copyright by ciphering a record signal when a digital video signal is compressed and encoded, and the signal is recorded/reproduced on a recording medium. CONSTITUTION:A digital video signal compressed and encoded by a compression encoder 2 is ciphered by a ciphering circuit 3 based on a key signal. This signal is encoded by an error correcting encoder 5, and recorded on a recording medium. At the time of reproducing, the signal is processed in a reverse order of the above operation, and a cipher is deciphered by the same key signal as that at the time of recording. Thus, since the ciphering is conducted after the signal is compressed and encoded, an efficiency of compressing and encoding the video having correlation in a vertical direction is not lowered. Since it can be ciphered at a low speed, realization of the circuit is facilitated.