title: Comment on "Cheating prevention in visual cryptography".
abstract: Visual cryptography (VC), proposed by Naor and Shamir, has numerous applications, including visual authentication and identification, steganography, and image encryption. In 2006, Horng  showed that cheating is possible in VC, where some participants can deceive the remaining participants by forged transparencies. Since then, designing cheating-prevention visual secret-sharing (CPVSS) schemes has been studied by many researchers. In this paper, we cryptanalyze the Hu-Tzeng CPVSS scheme and show that it is not cheating immune. We also outline an improvement that helps to overcome the problem.
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Chen
authors.forename: Gwoboa
authors.initials: G
authors.lastname: Horng
authors.forename: Du-Shiau
authors.initials: DS
authors.lastname: Tsai
mesh_terms: D000465:Algorithms; D003196:Computer Graphics; D016494:Computer Security; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D016247:Information Storage and Retrieval / Q000379:methods*; D010364:Pattern Recognition, Visual