A novel image encryption scheme using both pixel level and bit level permutation with chaotic map

Abstract

In cryptography, chaotic cryptosystem is one of the methods to carry out encryption and decryption of images. This paper introduces a new symmetric key encryption technique based on chaotic map, scan method and cyclic shift operation. The confusion and diffusion techniques are implemented using Hilbert curve and Henon map. To ensure image scrambling, both pixel level and bit level permutations are performed. A novel method is adopted for bit level permutation using cyclic shift operation. The key streams for cyclic shift and diffusion operations are generated from the Henon map. Final encrypted image is generated from the double scrambled image. The performance of the proposed method has been analyzed using various analyses like statistical analysis, entropy analysis, differential attack analysis, key sensitivity analysis and known plain text attack analysis. Experimental results show that the proposed image encryption technique resists various attacks and ensures high security. It also provides better performance when compared with several traditional and state-of-the-art image encryption methods.