基于自相似分形集抗幾何失真的特性和人眼的視覺系統特征，提出了一種首先利用
頻域變換確定水印嵌入區，然后將數字水印信息轉化為生成自相似分形集的IFS 系數，再把由該IFS 生成的自相似分形圖嵌入到圖像中的數字水印算法。并對該數字水印算法抗幾何攻擊性以及不可感知性進行了檢驗。
關鍵詞∶迭代函數系（IFS）；人眼視覺系統（HVS）；掩蔽效應 ； 數字水印

Study of Fractal in building up the Digital Watermark’s Robusting (1.School of Science, Lanzhou University of Technology, Lanzhou 730050 China ,2. School of Computer and Commucation ,LanZhou University of Technology ,LanZhou ,china, 730050） Abstract: Based on the strongly robusting character against geometric distortion of self-similar fractal and the character of Human Visual System(HVS),a new algorithm for digital watermark is put forward。The method operates in the frequency domain and spatial domain. The digital watermark information is transformed into coefficients of an IFS after the original image has been done frequency transformation, and then the self-similar fractal image created by this IFS is embedded into the special area of the image. The algorithm is tested in robusting against
geometric distortion and of imperceptibility of human eyes.
Keywords: iterated function system; human visual system; visual masking; digital watermarking