Dynamical analysis and image encryption application of a novel memristive hyperchaotic system

In this paper, a new four-dimensional memristive hyperchaotic system is constructed based on Liu chaotic system by introducing a flux-controlled memristor model. Then the dynamic characteristics of the new system such as phase portraits, dissipation, Lyapunov exponent and power spectrum are investigated. Subsequently, a novel image encryption algorithm is designed based on the chaotic sequence generated by the proposed hyperchaotic system combining the hash algorithm and DNA sequence operations. In this image encryption algorithm, the coupling relationship between plaintext and ciphertext is established by using the hash value of plaintext image obtained by hash algorithm, and then the plaintext is decomposed into eight bit-plane, to improve the efficiency of the algorithm, only the higher four bit-plane are selected for scrambling. After scrambling, the data stream is further processed by the DNA encoding/decoding rules and DNA sequence operations to obtain the intermediate ciphertext. Finally, the ultimate encrypted image is obtained by performing order and reverse-order diffusion operations at the pixel level on the intermediate ciphertext. Experimental results and security analysis show that the proposed algorithm has excellent image encryption performance and can resist a variety of common attacks against the image encryption system.