A secure image encryption algorithm based on chaotic maps and SHA-3

In this paper, a chaotic image encryption algorithm is suggested combining with double chaotic maps, SHA-3 Secure Hash Algorithm-3, and auto-updating system. To shuffle pixel positions, a matrix having same size of the plain-image is generated dependent on the plain-image in stage of permutation. Then, SHA-3 is taken to calculate its hash values used to produce control parameter and initial condition of Logistic map. After that, total permutation is implemented for row and column to exchange pixels, where auto-updating systems are established by different images acting like one-time pad. Furthermore, 3D chaotic cat map is employed to enlarge key space in diffusion process. Permuted image is firstly divided into four sub-blocks, which are queued randomly according to the key of Logistic map. The last sub-block is picked out to calculate the hash values using SHA-3, of which are assigned into three groups to update the initial conditions of 3D chaotic cat map performing like one-time pad again. Current sub-block is designed to influence next sub-block in diffusion process. As a result, the proposed algorithm can resist efficiently the chosen-plaintext and known-plaintext attacks. Experimental results are also given to explain the high security of the proposed method. Copyright © 2016 John Wiley & Sons, Ltd.