Authors: Pallavi Vijay Chavan; Mohammad Atique
Addresses: G.H. Raisoni College of Engineering, Nagpur, MH, India ' PG Department of Computer Science, S.G.B.A.U. Amravati, MH, India
Abstract: Threshold based hierarchical visual cryptography is a novel approach in the field of visual cryptography. THVC is encrypting the secret information in number of levels. THVC encrypts the secret in such a way that decoding is performed easily by human visual system. The authors used standard threshold of 0.5 to determine the existence of information in share. The authors have experimented THVC for multiple thresholds ranging from zero to one. Two different authentication models are proposed based on THVC: one way authentication model, and two way authentication model. Shares generated out of THVC are used for authentication. One-way hashing is applied on all the shares to reduce the time complexity. 100% randomness is observed in generated shares. The percentage of pixel expansion is found to be 0% during experimentation. The parameters like peak signal to noise ratio, pixel expansion ratio, and number of shares are evaluated and compared with existing figures.
Keywords: visual cryptography; secret sharing; authentication models; expansion ratio; security; thresholds; one-way hashing; peak SNR; signal to noise ratio; pixel expansion ratio; share numbers.
International Journal of Information Privacy, Security and Integrity, 2015 Vol.2 No.2, pp.159 - 175
Received: 01 Aug 2015
Accepted: 08 Oct 2015
Published online: 18 Mar 2016 *