The spatial-domain encryption of digital images based on high-dimension chaotic system

The Lorenz chaotic system is applied to the digital image encryption based on the thought of higher secrecy of high-dimension chaotic system in this paper. Firstly, the pretreatment to the real value chaotic sequences produced by the system is carried out. Secondly, the index matrix of pixel permutation is structured by this real value chaotic sequence. Finally, the spatial-domain encryption of digital image is realized in 8times8 block. The analysis and simulation indicates, after the pretreatment, the real value chaotic sequence has the better pseudo-random characteristic. Additionally, with the bigger secret-key space of the high-dimension chaotic system, the algorithm has the quite strong function of resisting decryption and resisting attack. Three-dimension outputs of the system can realize the parallel encryption of three or more images, so increase the encryption efficiency of the algorithm