A New Color Image Encryption Algorithm Based on Image Block Permutation and Diffusion with Fractional-order Chaos
Chunli Wang · Journal of Henan University · 2014
A new color image encryption algorithm is proposed based on image block permutation and diffusion,using the fractional-order chaotic system.First,the color plain image is converted into a gray-scale image,which is composed of the R,G,B components of the plain-image,and then we divide the gray-scale image into blocks.Secondly,the position of each image block varies according to a Logistic map.Finally,each component of the scrambled image is decomposed into two blocks,and the image pixels' values are modified and diffused simultaneously in a parallel manner with two rounds using the improved fractional-order chaotic sequences.Thus we obtain the cipher-image.Theoretical analysis and experimental results show that the presented encryption algorithm has fast speed,high security,good encryption/decryption effects,and can resist differential attack,statistical attack and cipher-text attack.