Patent ID: 7460667

Claim:
A method for decoding an auxiliary data bit embedded in a plurality of samples of a digital composite signal received from an encoder, said bit modulating a pseudo-random sequence at the encoder to provide a pseudo-randomly modulated auxiliary data sequence that replaces at least one least perceptually significant bit (LPSB) of each of the plurality of samples, comprising the steps of: (a) at a decoder, multiplying the auxiliary data sequence by a pseudo-random sequence corresponding to the pseudo-random sequence used at the encoder to provide corresponding multiplication values; (b) accumulating the corresponding multiplication values to obtain a correlation value; (c) comparing said correlation value to a threshold decision value; and (d) assigning a value to the auxiliary data bit according to said step (c); wherein: each sample comprises a plurality of bits; and a number of said LPSBs that is replaced in each of the samples is varied for different samples on an ongoing basis according to a desired perceptibility level of the auxiliary data sequence in the composite signal.