Encryption and Decryption of Digital Color Images Based on High Dimensional Chaotic Maps

摘要

The fascinating developments in digital image processing and network communications during the past decade have created a great demand for real-time secure image transmission over the Internet and through wireless networks. To meet this challenge, a variety of encryption schemes have been proposed. Among them, chaos-based algorithms have shown some exceptionally good properties in many concerned aspects regarding security, complexity, speed, computing power and computational overhead, etc. Chaotic system is suitable for image encryption because it has several good properties. In this paper, a new image encryption scheme is proposed which employs one of the three dynamic chaotic systems (Lorenz or Chen or LU chaotic system selected based on 16-byte key) to shuffle the position of the image pixels (pixel position permutation) and uses another one of the same three chaotic maps to confuse the relationship between the cipher image and the plain-image (pixel value diffusion), thereby significantly increasing the resistance to attacks. The proposed system has the advantage of bigger key space, smaller iteration times and high security analysis such as key space analysis, statistical analysis and sensitivity analysis were carried out. The results demonstrate that the proposed system is highly efficient and a robust system.