Abstract
For security reasons, more and more digital data are encrypted before being transferred or archived. This chapter focuses on data hiding (DH) methods in the encrypted domain. It describes a high-capacity DH method based on most significant bit prediction, which achieves very good results. DH is an approach used to conceal secret data inside a signal. Users may encrypt personal multimedia data before storing it on a cloud platform in order to preserve their privacy. The chapter describes the properties that define and categorize DH methods, namely the trade-off between embedding capacity and the quality of the reconstructed image, and approaches that can be used for the encoding and decoding phases. It then describes DH methods that considered to be particularly representative of the current state of the art. These are grouped according to key concepts: image partitioning, histogram shifting, encoding, prediction or public key encryption.