Chaotic Map for Securing Digital Content: A Progressive Visual Cryptography Approach

Progressive Visual Cryptography (PVC) is quite suitable for sharing sensitive digital data.Previous research on PVC, such as Fang et al. (2006) and W.P.Fang et al.(2008) were all carrying pixel-expansion problem and also gives a poor visual quality on the recovered stacked image. Recently, Hou&Quan (2011) have developed a progressive scheme for secret sharing. It is observed that shares generated by the scheme are free from pixel expansion problem, but shares are not fully secure. In this paper, a new progressive sharing algorithm based on logistic chaotic map has been proposed to overcome the said limitation of Hou (2011) scheme. The irregular outputs of the logistic map are used to encode a secret digital information carrying image. The performance of the algorithm in the scheme of Hou (2011) is critically analyzed and compared with new suggested scheme. Empirical results are presented to showcase the performance of the authors' proposed scheme in terms of its effectiveness (imperceptibility and security) and feasibility.