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.