ANTIPIRACY DEVICE AND METHOD FOR CINEMATOGRAPHIC AND VIDEO CARRIERS

摘要

Antipiracy device comprising a detection member (180) for detecting a mark signal inscribed on a "sound" track of a video tape and which may not be eliminated during a duplication, a detection member (181) for detecting at least one digitally coded message also inscribed in said track, a retrieval member for retrieving said coded message (187) and means (183-186) for enabling or inhibiting the exploitation of the tape by a television receiver (TV) as a function of the presence or the absence of the marking signal and of the coded message or messages and/or the change of the latter resulting from a duplication.