离散小波变换和混沌结合的数字图像水印算法  

DWT and Chaos Combined Digital Image Watermark Algorithm

作　　者：王强[1,2] 丁群[1] 张忠[1] 

机构地区：[1]黑龙江大学电子工程学院,哈尔滨150080 [2]中国人民解放军65923部队,154000

出　　处：《电子测量与仪器学报》2008年第5期16-20,共5页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金(No.60672011);黑江省科技攻关(No.GZ06A101)项目资助

摘　　要：提出了一种基于离散小波变换和混沌理论的数字图像水印算法。在水印嵌入过程中,首先对原始图像进行离散小波变换,提取其低频部分作为嵌入区域;然后利用混沌系统产生的混沌序列对水印进行加密,再将加密后的水印进行小波变换并提取其低频部分;最后将加密水印的低频部分嵌入到原始图像的低频部分中。水印提取过程需要原始载体图像,是一种明检测。通过水印相关系数NC和峰值信噪比PSNR评价水印算法性能。实验结果表明,提出的算法可以抵抗JPEG压缩、噪声、滤波等攻击,图像水印效果很好。In this paper, a digital image watermark algorithm based on discrete wavelet transform and chaos theory is proposed. During the embedding of the watermark, discrete wavelet transform is carried out firstly and its low frequency part is extracted and used as the embedding field; then the chaotic sequence is used to encrypt the watermark, and wavelet transform is performed on the encrypted part and the low frequency part is extracted; final- ly, the low frequency part of the encrypted watermark is embedded into that of the original image. The watermark extraction is a kind of non-blind detection as the extraction needs original image. The correlation coefficient NC and peak noise to signal ratio PNSR are used to evaluate the algorithm. Experiment results indicate that this algorithm can resist attacks of JPEG compression, noise, filtering and so on. The effect of image watermarking is very well.

关 键 词：小波变换 混沌 加密水印 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]