一种基于离散小波变换的数字水印技术  

An Algorithm of Digital Watermarking Based on Discrete Wavelet Transform

作　　者：傅锦伟[1] 李颖芳[1] 孙建洪[1] 

机构地区：[1]红河学院工学院计算机系,云南蒙自661100

出　　处：《湘潭大学自然科学学报》2011年第2期104-107,共4页Natural Science Journal of Xiangtan University

摘　　要：针对图像软件对宿主图像进行JPEG有损压缩、缩放、锐化等常见编辑操作会对嵌入的数字水印造成无意攻击,导致水印信息提取困难的问题,提出一种的基于离散小波变换技术的改进数字水印技术.首先考虑到JPEG标准压缩算法对亮度分量全保留的原理,选择宿主的亮度分量嵌入数字水印信息,以增强鲁棒性;然后根据人类视觉系统原理:人类对45°角分量最不敏感的原理选择YUV颜色模型中的Y分量的二级小波分解的对角区域cD2作为水印嵌入区;并在算法中通过控制嵌入信息强度满足了水印的隐蔽性.最终的实验结果表明该算法对JPEG有损压缩具有很强的鲁棒性,并对缩放、锐化、模糊和旋转等几种常见图像处理造成的无意攻击具有一定的鲁棒性.For against no intention attacking caused by general image editing process such as lossy JPEG compression, scaling and sharpen, etc, which result in the embedded watermark hard to extract, an improved algorithm of digital watermarking based on discrete wavelet transform （DWT） is proposed. Considering the characteristics of JPEG image compression algorithm, the watermark is embedded into the luminance channel of YUV color model for achieving strong robust in the proposed algorithm. The Human Visual System （ HVS） studies also show that visual perception is the least sensitive on the direction of 45°. For keeping embedded watermark invisible, only the diagonal component cD2 was chosen to embed watermark. Furthermore, the amplitude coefficients of embedded watermark will be limited. So both the greater invisibility and stronger robust of the proposed algorithm＇are achievod. The results show that the algorithm has very strong robust against lossy JPEG compression attack and stronger robust to against some kinds of no intention attacking caused by sealing, sharpen, blur and rotation processes.

关 键 词：离散小波变换 数字水印 水印嵌入 水印检测 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]