Chapter 2 - Frameworks for Data Hiding

Abstract

Data hiding is a mechanism for attaching an auxiliary signal to such information signals. The auxiliary message signal is inextricably tied to the information signal and persists independently of the means by which the information signal is disseminated. In the context of information hiding, the information signal is called the cover signal before the message signal is embedded into it and the stego signal after the message signal is embedded. The most important issues that arise in the study of data hiding techniques concern embedding and detecting mechanism, capacity, robustness, and transparency. The areas that contribute to the development of digital watermarking include at least the following: information and communication theory, decision and detection theory, signal processing and transforms, and cryptography and cryptographic protocols. Each of these areas deals with a particular aspect of the data hiding problem. Information- and communication-theoretic methods deal with the data embedding side of the problem. Data hiding techniques are characterized by the embedding and extraction techniques employed. Methodologically, the proposed embedder/detector designs can be categorized into two main groups: additive spread spectrum-based methods and quantization-based methods.