METHOD FOR SECURELY DELIVERING AUDIOVISUAL SEQUENCES, DECODER AND SYSTEM THEREFOR

摘要

The invention concerns a method for delivering a nominal audiovisual stream to a receiving site, the nominal audiovisual stream comprising nominal coefficients, the method including: a step which consists in modifying in the nominal audiovisual stream at least one nominal coefficient among said nominal coefficients to generate a main digital stream; generating a complementary information so that the nominal audiovisual stream is capable of being implemented from said complementary information and the main digital stream at the receiving site. The method is characterized in that the receiving site comprises a secure gateway, and in that the method includes steps whereby: the secure gateway performs cryptographic operations on the complementary information; the gateway transmits the complementary information to an audiovisual peripheral so as to enable the nominal audiovisual stream to be implemented by at the audiovisual processing peripheral.