A Novel Semi-blind Watermarking Algorithm Based on Fractal Dimension and Image Feature  

作　　者：NIRongrong RUANQiuqi 

机构地区：[1]InstituteofInformationScience,BeijingJiaotongUniversity,Beijing100044,China

出　　处：《Chinese Journal of Electronics》2004年第2期293-299,共7页电子学报（英文版）

摘　　要：This paper presents a novel semi-blind watermarking algorithm based on fractal dimension and image feature. An original image is divided into blocks with fixed size. According to the idea of the second generation watermarking[1], the image is analyzed using fractal dimension to attain its feature blocks containing edges and textures that are used in the later embedding process and used to form a feature label. The watermark that is the fusion of the feature label and a binary copyright symbol not only represents the copyright symbol, but also reflects the feature of the image. Arnold iteration transform is employed to increase the security of watermark. Then,DCT (Discrete cosine transform) is applied to the feature blocks. The secure watermark that is adaptive to the individual image is embedded into the relations between middle-frequency coefficients and corresponding DC coefficients. The detection and extraction procedure is a semiblind one which does not use the original image but the watermark. Only those who have the original watermarkand the key can detect and extract the right watermark.This makes the approach authentic and have high securitylevel. Experimental results show that this algorithm can get good perceptual invisibility, adaptability and security.And it is robust against cropping, scribbling, low or highpass filtering, adding noise and JPEG compression.

关 键 词：半盲水印 分形尺寸 图象特征 离散余弦变换 迭代变换 关系系数 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]