Encrypted images-based reversible data hiding in Paillier cryptosystem

Abstract

Homomorphic public key technology effectively protects privacy, allowing algebraic operations directly in the cipher-text. Therefore, it has been extensively studied in the field of cloud computing. In this study, an encrypted image-based data hiding (EIRDH) algorithm with homomorphic public key cryptosystem is presented. The key contributions are these two sides. (1) An improved fast Paillier homomorphic public key cryptosystem system is proposed for encrypting image. It improves the efficiency of encryption operations greatly. (2) A difference expansion (DE) scheme is developed by exploiting the cover pixel to construct a new pair of pixels for data hiding. Compared with other methods, the experimental results show that, the proposed method has larger payload and higher stego-image quality. It accomplishes the image quality’s increasing instead of general decreasing.