A Novel Hierarchical Secret Image Sharing Scheme with Multi-Group Joint Management

With the spread of the Internet, the speed of data spread is getting faster and faster. It benefits us a lot but also brings us many potential security problems, especially the problem of privacy leakage. For example, more and more people choose to store their private images in the cloud. Secret image sharing as a significant method has been widely applied in protecting images in the cloud, which reduces the risks of data leakage and data loss. Generally, the secret image sharing scheme would encrypt the secret image into a series of shares and then stored these shares in a cloud. However, when this cloud has been attacked, the secret may meet a risk of leakage. A solution to solve the problem is that the generated shares are distributed storage in multiple clouds. Each cloud is independent and all clouds can have a collaboration to manage the secret image. To address this issue, a novel hierarchical secret image sharing scheme with multi-group joint management is proposed in this paper, which is suitable for protecting the security of the secret image by distributed storage over multiple clouds. In the proposed scheme, the secret image would be shared among multiple groups with different thresholds. The number of each group’s shareholders is determined by a sequence of thresholds. Therefore, the proposed scheme is a hierarchical secret image sharing scheme in which the secret image can be reconstructed if and only if the number of shares has met all threshold conditions. In addition, the generated shares have the same weight, which is more suitable for universal applicability. Both the system analysis and the simulation results prove that the proposed scheme is efficient and practical.