A blind watermarking scheme based on structured codebooks

Blind digital watermarking is the communication of information via multimedia host data, where the unmodified host data is not available to the watermark detector. Many watermarking schemes suffer considerably from the remaining host-signal interference. For the additive white Gaussian case, M.H.M. Costa (1983) showed theoretically that interference from the host can be eliminated. However, the proof involves a huge, unstructured, random codebook, which is not feasible in practical systems. We present a suboptimal, practical scheme that employs a lattice-structured codebook to reduce complexity. The performance of the proposed scheme is compared to the information-theoretic limit and similar recent proposals.