Abstract: Based on Logistics and Standard Map,a new image encryption algorithm was proposed. By using the properties of chaotic map such as sensitive to initial values, sensitive to parameters and the statistic specialty of white noise,the confusion system was designed through discrete chaotic map and standard map. This confusion is dependent on the secret keys generated by a different chaotic system. I}hen changed the pixel values of encrypted image through the substitution system and made pixels associated with each other. At the same time, every pixel value was diffused to others.The system contains confusion, substitution and diffusion, which arc necessary factors for a good cryptosystem. The experimental simulation and analysis illuminate that the algorithm has such advantages: larger key space, easily realized and perfect statistical characteristics.

Key words: Logistic map, Standard map, Image encryption, Image scrambling transform