Toward a secure protection scheme for visual secret sharing

Abstract

Visual cryptography, proposed by Naor and Shamir in 1995, is a scheme which decodes messages by using human visual sensitivity. Cheating has been proved to be possible in visual cryptography. We propose a cheating prevention scheme which precludes members of a group from collusive cheating by using additional images for verification. In each pair of shared images, we detect cheating by mutually verification. The result of verification is clear and directly perceived by the senses. It is a practical technique using authenticating images while the structure of the secret is complex.

Keywords:

• Visual secret sharing
• Collusive cheating
• Mutual verification
• Image processing

Acknowledgements

The authors would like to give their appreciation to the anonymous referees for their valuable suggestions and comments. This research was partially supported by the National Science Council, Taiwan, under contract no. NSC 101-2221-E-030-018.