Correlation-and-Bit-Aware Spread Spectrum Embedding for Data Hiding

This paper proposes a correlation-and-bit-aware concept for data hiding by exploiting the side information at the encoder side, and we present two improved data hiding approaches based on the popular additive spread spectrum embedding idea. We first propose the correlation-aware spread spectrum (CASS) embedding scheme, which is shown to provide better watermark decoding performance than the traditional additive spread spectrum (SS) scheme. Further, we propose the correlation-aware improved spread spectrum (CAISS) embedding scheme by incorporating SS, improved spread spectrum (ISS), and the proposed correlation-and-bit-aware concept. Compared with the traditional additive SS, the proposed CASS and CAISS maintain the simplicity of the decoder. Our analysis shows that, by efficiently incorporating the side information, CASS and CAISS could significantly reduce the host effect in data hiding and improve the watermark decoding performance remarkably. To demonstrate the improved decoding performance and the robustness by employing the correlation-and-bit-aware concept, the theoretical bit-error performances of the proposed data hiding schemes in the absence and presence of additional noise are analyzed. Simulation results show the superiority of the proposed data hiding schemes over traditional SS schemes.