Chaos-Based Image Encryption Using an Improved Quadratic Chaotic Map

In recent years, chaos-based image encryption has become an efficient way to encrypt images due to its high security. In this paper, we improve the classical Quadratic chaotic map to enhance its chaotic properties and use it for image encryption. Compared with the classical Quadratic map, the proposed Quadratic map demonstrates better chaotic properties for encryption such as a much larger maximal Lyapunov exponent. The proposed image encryption scheme is based on two chaotic maps. The first map is the Chepyshev chaotic map, which is used for the permutation of the pixels of the image. The permuted image is subjected to the diffusion process using the improved Quadratic map in an efficient encryption algorithm which its key is related to the original image. The main advantages of the proposed scheme are the large key space and its resistance to various attacks. Simulation results show that the proposed scheme has a high security level with low computational complexity, which makes it suitable for real-time applications.