Abstract: The present invention is a method and system which extracts, manipulates and embeds data from a compressed and standard compliant video bitstream which may be used for digital rights management, e.g. controlling access to a bitstream or for authenticating a video bitstream. The method embeds binary data bits into compressed and standard compliant video bitstream with minimal visual artifacts. The method first parses the compressed video bitstream and locates coded blocks. The codeword C for the last triplet in the original block(RUNc,LEVELc, LASTc=1) is replaced by the VLC code word C? for the last triplet (RUNC,LEVELC, LASTC?=0). A codeword corresponding to a triplet with LAST=1 is placed after C? whose sign bit “s” can be either 0 or 1 and is an embedded data bit, and can be used for authentication.

Abstract: A compliance preserving method and device for access control of a standard compliant multimedia bitstream. The access control method performs selective encryption on information in the bitstream and then remaps the encrypted information into the bitstream, to provide a multimedia bitstream that is accessible to users with a proper key. The method can be applied to both error resilient mode and non-error resilient mode bitstreams. Additionally, the selective encryption method can be used with variable length code (VLC) codewords or fixed length code (FLC) codewords of a bitstream.