Data transmitting method, data recording apparatus, data record medium and data reproducing apparatus

摘要

A data transmitting method for preventing direct copying of digital bi-level signals. When processing input digital data from an input terminal 11 by circuits 13 to 16, modulating the data by a modulation circuit 17 and appending synchronization signals by a synchronization appendage circuit 18, the synchronization signals are appended using a synchronization format which is different from the synchronization format conforming to the standard and which is usually not used. For example, the synchronization pattern different from the regular synchronization pattern may be used, or the synchronization signal may be inserted at a position different from the regular position. If attempts are made for direct copying of the digital bi-level signal having such synchronization format, synchronization may be disengaged, for example, thus obstructing and prohibiting duplication.