COPY PROTECTION FOR OPTICAL DISCS

摘要

A recordable disc is premastered to carry the publisher's data (40) and additionally data patterns are recorded on the disc. The nature and/or size of the data patterns is chosen to ensure that DSV problems are caused when the recordable disc is read such that the data patterns define a blocking file. Information as to the existence and location of the data patterns is provided on the recordable disc. An encoder (44) may be enabled to access the existence and location information such that it does not read the blocking file whereby the encoder is able to write the publisher's data to a disc (50). This technique may be used to prevent mastering of discs by encoders which are not arranged to add an authenticating signature to the mastered disc.