An Improved Approach for Multiple Image Encryption Using Alternate Multidimensional Chaos and Lorenz Attractor

Abstract

This chapter proposes a multiple image encryption method based on multi-dimensional chaotic equations. Four-dimensional differential chaotic equations of Lorenz attractor have been used to generate the initial security key, and alternate logistic maps have been used for encryption. Initially, three input images are used in a matrix form, where size of each image is M×N, and a composite image is derived by combining the one dimensional matrix of the input images, where size of the composite image matrix is 3×(M×N). Secondly, Lorenz attractor (LA) generates the security key using the composite matrix, and then alternate logistic map is applied with one-dimensional and two-dimensional logistic maps to confuse the matrix. In every iteration of logistic maps, XOR operation is used to encrypt the composite image, and at last, transformation is applied to diffuse the matrix. Finally, the encrypted composite image is obtained in the form of a confused matrix. The proposed algorithm reduces the correlation, increases entropy, and enhances performance of encryption.