基于QIM的数字图像盲水印算法  

QIM-based digital image watermarking scheme

作　　者：徐端全[1] 朱光喜[1] 

机构地区：[1]华中科技大学电子与信息工程系,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2008年第7期10-13,共4页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60502023);湖北省自然科学基金资助项目(CGZ0223)

摘　　要：提出了一种DCT域量化索引调制水印算法.水印嵌入在经过像素置换的相邻图像块DCT系数的差值上,根据二值水印的信息位对该差值进行正/负调制,从而实现水印的嵌入.为了平衡不可见性和鲁棒性的要求,根据人类视觉系统的掩蔽特性及图像局部特征对不同嵌入点的嵌入强度进行自适应调整,在确保视觉质量的前提下,得到良好的水印性能.实验结果显示该算法对各种常见图像处理具有良好的鲁棒性.Quantization index modulation is a well-known method used for blind watermarking algorithm.A new QIM watermarking scheme in discrete cosine transform（DCT） domain is proposed.Watermark was embedded into the difference of DCT coefficients from neighboring blocks,which exchange pixels to each other before embedding.A bit of the watermarking could be embedded by modulating the difference to positive or negative.To keep the balance between invisibility and robustness,strength factor will be adjusted adaptively for each embedding position based on the masking feature of HVS.Using this adaptive adjusting,the watermarking performance is improved while keeping well perceptual effect.The experimental results show that this watermarking scheme is robust to various image processing.

关 键 词：数字水印 量化索引调制 离散余弦变换 人类视觉系统 盲检测 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]