Visual Cryptography and Secret Image Sharing

10

Cheating Prevention in Visual Cryptography

Chen Yu-Chi, Horng Gwoboa and Tsai Du-Shiau

National Chung Hsing University, Taiwan

National Chung Hsing University, Taiwan

Hsiuping Institute of Technology, Taiwan

CONTENTS

10.1 Introduction

10.2 Preliminaries

10.2.1 Visual Cryptography

10.2.2 Cheating in VC

10.3 Cheating Prevention Schemes

10.3.1 HCT1 and HCT2

10.3.2 HT

10.3.3 TCH

10.3.4 PS1 and PS2

10.4 Analysis of Cheating Prevention Schemes

10.5 Conclusions

Bibliography

10.1 Introduction

In 1994, Naor and Shamir proposed a variant of secret sharing called Visual Cryptography (VC) [9], where the shares given to participants are xeroxed onto transparencies. If X is an authorized subset, then the participants in X can visually recover ...