Color image encryption based on hybrid hyper-chaotic system and cellular automata

This paper proposes a new hybrid chaotic map and a different way of using optimization technique to improve the performance of encryption algorithms. Compared to other chaotic functions, the proposed chaotic map establishes an excellent randomness performance and sensitivity. Based on its Lyapunov exponents and entropy measure, the characteristics of the new mathematical function are better than those of classical maps. We propose a new image cipher based on confusion/diffusion Shannon properties. The substitution phase of the proposed encryption algorithm, which depends on a new optimized substitution box, was carried out by chaotic Jaya optimization algorithm to generate S-boxes according to their nonlinearity score. The goal of the optimization process is to have a bijective matrix with high nonlinearity score. Furthermore, a dynamic key depending on the output of encrypted image is proposed. Security analysis indicates that the proposed encryption scheme can withstand different crypt analytics attacks.

An image encryption scheme based on a new hybrid chaotic map and optimized substitution box

In this paper, a new and efficient pixel-level image encryption algorithm is presented. In contrast to the traditional permutation–diffusion architecture, the proposed method enhances the connection between position shuffling for pixels and value changing for grayness. As a result, the separate attack becomes more difficult when attacking our structure of permutation–rewriting–diffusion (PRD). Before the diffusion operation, a rewriting function is applied to the permuted image in a simple way, which can be seen as a remedy for permutation’s inability to change the frequency of pixels. Moreover, the keystream is designed dependent upon the plain-image. Therefore, the proposed method can disturb the chosen plain-image and known plain-image attacks. Experimental results together with security analysis also show good efficiency of the PRD mechanism. Compared to some bit-level-based image encryption algorithms, our method shows increased faster speed and satisfies the performance requirements of real-time communication.

An efficient pixel-level chaotic image encryption algorithm

An image encryption algorithm based on a hidden attractor chaos system and the Knuth–Durstenfeld algorithm

A new quantum image encryption scheme is suggested by using the iterative generalized Arnold transforms and the quantum image cycle shift operations. The times of the quantum image cycle shift operations are controlled by a hyper-chaotic sequence generated by a new 4D hyper-chaotic system. The image pixels are scrambled by the iterative generalized Arnold transform, and the values of the pixels are altered by the quantum image cycle shift operations. The four initial conditions of the new 4D hyper-chaotic system are exploited to control the two parameters, the iterative rounds of the generalized Arnold transform and the times of the quantum image cycle shift operations, respectively. Thus, the main keys of the proposed quantum image encryption scheme are the four initial conditions of the new 4D hyper-chaotic system and the key space is relatively large enough. Simulation results and theoretical analyses demonstrate that the proposed quantum image encryption scheme outperforms its classical counterparts apparently.

Quantum image encryption scheme with iterative generalized Arnold transforms and quantum image cycle shift operations

A quantum realization of the generalized Arnold transform is designed. A novel quantum image encryption algorithm based on generalized Arnold transform and double random-phase encoding is proposed. The pixels are scrambled by the generalized Arnold transform, and the gray-level information of images is encoded by the double random-phase operations. The keys of the encryption algorithm include the independent parameters of coefficients matrix, iterative times and classical binary sequences, and thus, the key space is extremely large. Numerical simulations and theoretical analyses demonstrate that the proposed algorithm with good feasibility and effectiveness has lower computational complexity than its classical counterpart.

Dong Ju Pei

Papers

Quantum image encryption based on generalized Arnold transform and double random-phase encoding