A New Image Encryption Scheme Based on Hyperchaotic System and SHA-2

Abstract

This paper presents a new image encryption scheme by using a four-dimensional hyperchaotic system and adopting permutation-diffusion architecture. The initial conditions of the hyperchaotic system are modified by the 256-bit digest of the plain image to increase the sensitivity of the cipher to the plain image. An enhanced nonlinear equation is applied in the diffusion process for the better encryption result. The experiment results show that the proposed scheme has large key and subkey space, high key sensitivity, good information entropy, and capability to resist statistical and differential attacks.