A Parallel Encryption Algorithm for Color Images Based on Lorenz Chaotic Sequences

This paper presents a chaos-based encryption algorithm for colors images in spatial domain. Firstly, the pretreatment is carried out to three chaotic sequences produced by Lorenz system. Then these sequences are used to structure scrambling index matrixes. Finally, it is realized to parallel scrambling for three colors of RGB images in spatial domain. The analysis and simulation indicates the pretreated sequences have better pseudo-random characteristic. Encrypting efficiency of the algorithm is increased greatly used three sequences at one time and scrambled to 8times8 blocks of three colors. Additionally, as a result of more secret-key space than low-dimension systems, the algorithm has very strong secrecy and security