Chaotic image encryption based on finite field bidirectional diffusion and steganography

This paper proposes an algorithm combining image encryption and steganography which provides double protection for images that need to be kept secret. First, a new Three-Dimensional (3-D) fractional-order memristive Hindmarsh-Rose (HR) neuron model is constructed. It has highly complex and unpredictable dynamic behavior, which can produce complex state transition phenomena such as period, period-doubling bifurcation, chaos and hyperchaos. Then, the finite-field bidirectional diffusion algorithm was used to perform nonrepetitive scrambling and bidirectional diffusion of the image. Finally, the Least Significant Bit (LSB) algorithm is used to hide the encrypted image in the carrier image that is normally transmitted. Experimental results show that the algorithm has a large key space, which is robust, has high computational time efficiency, and can resist various attacks.