On the security of threshold random grid-based visual secret sharing

摘要

Visual secret sharing (VSS) technology encodes a secret image into some share images for sharing some classified information. Only when the participants gather and stack their share pictures the secret image would be reconstructed and recognizable by the human visual system. Two well-known encoding ways of VSS, visual cryptography (VC) and random grid (RG), have been developed in recent years. As both VC and RG have been considered as a secure way for communicating with high security, they have been pointed out with cheating problems. In this paper, we propose two RG-based VSS schemes with fraud prevention for the cases of (2,n) and (k,n). The experimental results and the analysis of security and contrast show that the proposed method is efficient and practical.