Image Encryption Using Fractional Order Linear-Nonlinear Chaos

Abstract

A fractional order chaos system is first designed. It is a linear-nonlinear hybrid using fractional order logistic map. The fractional order chaos system is closer to the real nature phenomena and has better cryptography features than the integer order chaotic systems in dynamics, such as larger range of key space and almost no periodic windows in bifurcation diagrams. Then, we propose an image encryption scheme employing the superior chaotic features of the fractional order chaos system. Which chaotic sequences generated are used for permutation and addition/subtraction operation of encryption depends on the plaintext image. Security analysis and test results indicate that our encryption scheme has a high efficiency and superior security.