A Simultaneous Scrambling and Diffusion Color Image Encryption Algorithm Based on Hopfield Chaotic Neural Network

The classic scrambling-diffusion structure for image encryption is vulnerable to be attacked. The scrambling and diffusion process can be cracked separately due to the two processes are independent. In this paper, we proposed a novel color image encryption algorithm which can overcome the problem. In the proposed algorithm, firstly, the first diffusion is performed simultaneously with the first scrambling which can resist the attacker to separately crack the scrambling or diffusion. Then, the second diffusion matrix generated from the Hopfield chaotic neural network (HCNN) which is related to the plaintext is performed which can not only resist common chosen-plaintext attack, but also improved the key sensitivity. Finally, a second scrambling is performed on some special pixels to further improve the security. Experiments and security analysis indicate that the proposed algorithm has an excellent performance in image encryption and various attacks.