Sharing Visual Secrets Among Multiple Groups With Enhanced Performance

An almost unexplored research topic in visual secret sharing (VSS), i.e., sharing different visual secrets among various groups, is investigated in this article. Generally, multiple groups are cooperated together to encrypt multiple visual secrets, where every group is correlated with a VSS scheme to share one secret and each participant receives only one shadow. Such a cooperative system is referred to as cooperative VSS (CVSS). In this paper, we develop a general construction for CVSS with improved computational overhead. The basis matrices for generating the shadows are easily obtained. To improve the recovered image quality, an efficient XOR-based CVSS (XCVSS) is given. Furthermore, to fulfill the requirement of implementing complex sharing policy, the XCVSS is extended to collaborate general access structure (GAS) VSS schemes together. Theoretical and experimental results and comparisons are illustrated to demonstrate the advantages of the proposed techniques.