Image encryption based on hyper-chaotic multi-attractors

Linear time-delay feedback method makes the stable system generate the infinite-dimensional hyper-chaos, which possesses more than one positive Lyapunov exponent, infinite-dimensional, a wider chaotic parameter range, and multi-attractors, including the single-scroll attractor, the double-scroll attractor, and the composite multi-scroll attractor. The infinite-dimensional hyper-chaotic multi-attractors Chen system generated by linear time-delay feedback (HCMACS) is used for image encryption. Firstly, the state time sequences of the infinite-dimensional HCMACS are preprocessed to achieve the ideal statistical property. Secondly, two random matrices generated by random number generators are used to expand the image size. Finally, the preprocessed chaotic sequences are used to confuse and diffuse the expanded digital image to obtain the encrypted image. The special feature of the proposed method is the theoretically infinite-dimensional secret key space. Results of analysis and computer simulation indicate that the encryption algorithm has good encryption performance, which can effectively resist various attacks.