Lattice Costa schemes using subspace projection for digital watermarking

Abstract

Abstract A general watermarking scheme employing lattice quantization is proposed and analyzed. This scheme is based on the equivalence of embedding in digital watermarking and transmission over so‐called modulo‐Λ channels. Main intention is to increase the maximum data rate which can be transmitted reliably (Shannon capacity of the scheme), tolerating a certain embedding and attack distortion. For this, a general concept of embedding in a subspace rather than the signal space itself is discussed, by which the capacity can be increased particularly for very low watermark‐to‐noise ratios. Numerical results show that the eight‐dimensional Gosset lattice seems to be a promising compromise between achievable capacity and complexity in blind digital watermarking. Copyright © 2004 AEI