Reversible Data Hiding Algorithm in Encrypted Domain Based on Matrix Secret Sharing

Focused on the problems of user privacy disclosure and ciphertext data management in cloud service environment, this paper proposes a reversible data hiding algorithm in encrypted domain based on matrix secret sharing. Firstly, the matrix secret sharing of the pixels of the encrypted image was used to obtain n shares, in the process of constructing shared vectors for secret segmentation, the random variables involved in encryption and the location index of ciphertext feedback were used to construct the mapping relationship between them and the secret data to be embedded to generate redundant space for data embedding. Finally, the overflow pixels were processed, and the edge information was embedded by differential extension technology to obtain n marked encrypted images. The experimental results showed that the algorithm has complete reversibility. In contrast to the current algorithms, the embedding rate of the algorithm was greatly improved. The maximized embedding rate of the (3,4)-threshold scheme was 4.00bpp, and the maximized embedding rate of the (5,5)-threshold scheme was 6.40bpp, and the statistical characteristics such as correlation coefficient of the marked encrypted images were consistent with those of random image, and the security was high. The algorithm not only has the functions of privacy data protection and ciphertext authentication management, but also has the disaster recovery feature to realize the multi-party security storage of data.