Image Encryption Based On The Orbit Ergodicity Of Chaotic Systems

With the rapid development of network technology and extensive application of information systems, more and more information transmitted through the network. As one of the major media information, digital images have some features such as bulk data capacity and high correlation among pixels. Conventional encryption algorithms such as DES,AES and RSA are not suitable for real-time requirements of practical digital image encryption. In recent years, the study of digital image encryption algorithm is a hot spot. In particular, digital image encryption schemes based on chaotic encryption systems have been extensively researched.The fundamental properties of chaotic systems, such as high sensitivity to initial conditions and parameters, pseudo-randomness and ergodicity, are close to the structure of cryptography. So the chaotic dynamical systems are widely used to encrypt and hide information.The main contributions of the paper are:(1) A novel image encryption scheme based on the chaotic orbit ergodicity of Arnold transformation is proposed. In addition, the coupled lattice map is applied on the diffusion process to improve the security of the encryption system. The algorithm is verified and analyzed by simulations.(2) A novel image scrambling scheme based on the improved baker transformation is proposed. And image fusion scheme based on wavelet transform is proposed. Simulation results show that the proposed scheme could improve the scrambling degree and has big enough key space as well. The statistical analysis results show that it provides an efficient and secure way against statistical attack; it is robust against cropping and noise attack and so on as well.