Colour Image Encryption method using Multiple chaotic maps and DNA Encoding

Abstract

This paper proposes an encryption scheme that combines chaotic maps, SHA-2 hash function and a novel conditional shift scheme based on the Zaslavskii map. The scheme first scrambles the image using Arnold map and generates a mask image using the combined logistic-tent map, then the hamming distance is calculated between the images. DNA encoding is then performed on both images based on rules selected by a combined logistic-tent map followed by diffusion using the exclusive-OR method. Confusion is then carried out using a novel conditional shift scheme based on Zaslavskii map. Finally,another diffusion operation is carried out to generate the cipher image.Through analysis and simulation, the encryption scheme has been shown to provide high security.