中文摘要：

将分形编码和骑士巡游相结合，提出一种基于分形和骑士巡游的图像压缩加密算法。首先用骑士巡游产生的路径作为密钥，路径用矩阵表示，矩阵中的每一元素与图像分形编码中的每个值域块相对应。然后按照骑士巡游的路径，从某个元素开始依照某个步长的顺序进行分形编码，为保证图像质量可以进行四叉树分裂。解码是其逆过程。用MATIAB对该算法进行仿真实验，测试了置乱度、密钥敏感性，在保证一定解码图像质量的情况下，压缩比优于JPEG。

英文摘要：

An image compressing and encrypting approach is proposed. Firstly ,the route which the knight tour generated is used as a secret key,and it is expressed with matrix,each element in the matrix corresponds to the range block in the image fractal coding. Then carry out fractal coding acted on the route and start from some element with some step. Quad-tree is used to ensure the decoding image quality. The decoding is the inverse process of cod- ing. Experiments test the scrambling measure and sensitivity of secret key ,and show that the compression ration is better than JPEG under some decoding image quality.