Reversible data hiding in encrypted images with additive and multiplicative public-key homomorphism

摘要

Public-key homomorphism is an efficient technique of reversible data hiding in encrypted images (RDHEI). The existing public-key homomorphism based RDH-EI schemes benefit from the additive homomorphism of public-key encryption. In this paper, a theoretical analysis of public-key homomorphism based RDH-EI is given, which makes both additive homomorphism and multiplicative homomorphism available. Thus more homomorphic public-key encryptions can be used to construct RDH-EI schemes. By the theoretical analysis, lossless recovery of directly decrypted image is obtained. And the embedding rate can reach 1 bit per pixel (bpp) or more regardless of the pixel distribution of natural images. In addition, two novel public-key homomorphism based RDH-EI schemes using additive homomorphism and multiplicative homomorphism, respectively, are introduced. Experimental results are presented to illustrate the effectiveness and superiority of the proposed methods. (C) 2019 Elsevier B.V. All rights reserved.