An improvement over an image encryption method based on total shuffling

Confidentiality is an important issue in transmitting digital images over public networks such as the Internet. Image encryption is a useful solution to achieve confidentiality. Among existing encryption schemes, chaos-based approach has suggested fast, efficient and highly secure algorithms. Recently an efficient image encryption method based on chaos and permutation–diffusion architecture is suggested in [G. Zhang, Q. Liu, Opt. Commun. 284 (2011) 2775–2780]. However, the plain-text sensitivity, as reported by the authors, is not satisfying and it is recommended to iterate the algorithm more than twice to get a good ability to resist differential attack. The aim of this paper is to promote the plain-text sensitivity of their approach. As a result, the diffusion performance is significantly enhanced and the overall security of the image cryptosystem is improved. Results of various analyses and computer simulations confirm that the new algorithm has high security and is suitable for practical image encryption.