关键词: 图像置乱，Fibonacci双置乱，均匀分块，相关性

Abstract: Image scrambling is one of the important means to realize image encryption and the ultimate purpose of scrambling is to change the pixel position or the gray value, change the statistic information of the image, so as to a- chieve the purpose of image encryption. To enhance the effect and performance of images scrambling, from the perspec- five of uniform blocking,a kind of improved double scrambling algorithm of Fibonacci transforms was put forward. At first, plain image was carried out, using uniform blocking algorithm, and each sub-block pixel was fully diffused to other sub-blocks in turn to weaken the image correlation between adjacent pixels effectively. Next, scrambling algorithm shuf- fled the pixels' position of each blocks to weaken the image spatial correlation by using Fibonacci. Finally, srambling al- gorithm shuffled the pixels' value of the whole image to weaken the iamge color correlation by using Fibonacci. hhe ex- perimental results demonstrate that this algorithm can not only reduce the correlation of image adjacent pixels in essence but also has strong ability against shearing and common noise attacks in some degree, and it improves the encryption system's security by utilizing dual-key cipher.

Key words: Image scrambling, I}oublc scrambling algorithm of Fibonacci transformation, Uniform block, Rclcvance