Biblio

The paper presents a cryptanalysis of an enhanced sub-image encryption method recently proposed by Wang et al. in Optics and Lasers in Engineering 86(2016). Their paper shows that a parallel sub-image encryption method proposed by Mirzaei et al. in Nonlinear Dyn. 67(2012) could be attacked by chosen plaintext attack and proposed an enhanced sub-image encryption method claimed to completely resist the chosen plaintext attack. However, the enhanced sub-image encryption method also has some weakness, such as the key streams are independent with the plain-image. In this paper, one chosen plaintext attack type of cryptanalysis is presented for the enhanced sub-image encryption method and completely broken the enhanced sub-image encryption method. The experimental results indicate that the enhanced sub-image encryption method is weak against chosen plaintext attack and should be improved for practical application.

In this paper, a novel chaotic image encryption scheme based on the inverse fractal interpolation function system is proposed. The inverse fractal interpolation function system associated with fractal interpolation surface is applied to generate chaotic sequences. The derived sequences are then employed to permute the pixel positions to get the shuffled image by chaotic sequence sorting. The obtained chaotic sequences are then quantized to yield one pseudo-random gray value sequence used to perform diffusion to enhance the security. The security and performance of the proposed image encryption scheme have been analysed, including histograms, correlation coefficients, information entropy, differential analysis, etc. All the experimental results suggest that the proposed image encryption scheme is robust and secure and can be used for secure image and video communication applications.