Multi-bit watermarking scheme based on addition of orthogonal sequences

Abstract

In this paper, a scheme of watermark embedding based on a set of orthogonal binary sequences is introduced. The described technique is intended to be incorporated into various public watermarking frameworks developed for different digital media including images and audio signals. Unlike some previous methods using PN sequences in which each sequence carries only one bit of the watermark data, the proposed approach maps a number of bits to a single sequence from an orthogonal set. Both analytical and experimental studies show that, owing to the full exploitation of information carrying capability of each binary sequence, the performance is significantly improved compared with previous methods based on a one-bit-per-sequence technique. © Springer-Verlag Berlin Heidelberg 2003.