METHOD AND DEVICE FOR PROCESSING SIGNAL, METHOD AND DEVICE FOR REPRODUCING SIGNAL AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To easily prevent the duplication of a recording medium to which information whose copyright protection is required is recorded. SOLUTION: In a signal processing system, an information data block including enciphered main data and an error correction code is composed of symbols of M rows by N columns (M×N), one frame is divided into R frames, a synchronizing signal is added to each frame, and data of each frame are modulated by a modulator and then recorded on a recording medium or transmitted to a transmission line. A cryptographic key that enciphers the main data is modulated by another modulator different from the modulator for the information data block signal.