Double scramb about color image based on Fan Transform

Fan Transform is a new scrambing method and in this paper we do Fan Transform to the color image in position and gray, in this way the image became desultory and the image´s texture characteristics and statistical information were also changed, since the Fan Transform have inverse transform we can also restore the original image[8]. And the difficulty of cracking scrambling is related to the type and the times of transform, and Fan Transform has many types, so it increases the difficulty of cracking, and thus enhances security of it.