基于DWT域对数量化索引调制的数字水印算法  

LOGARITHMIC QUANTIZATION INDEX MODULATION DIGITAL WATERMARKING ALGORITHM BASED ON DWT DOMAIN

作　　者：汤永利[1] 张亚萍[1] 叶青[1] 闫玺玺[1] 高玉龙[1] 

机构地区：[1]河南理工大学计算机科学与技术学院,河南焦作454000

出　　处：《计算机应用与软件》2017年第8期206-212,共7页Computer Applications and Software

基　　金：国家自然科学基金项目(61300216);河南省科技厅项目(152102410048;142300410147);河南省教育厅项目(12A520021;16A520013);河南理工大学博士基金项目(B2013-043;B2014-044)

摘　　要：为了提高水印的透明性和鲁棒性,解决QIM均匀量化不适用于非均匀信号的问题。引入μ律技术,将小波分解与对数量化索引调制结合,提出基于DWT域的对数量化索引调制数字水印算法。算法对原始图像进行离散小波变换,对变换后的近似部分系数运用μ律函数,再用QIM方法嵌入二值水印。选择合适的嵌入位置,通过对量化步长和参数进行讨论得到其最优值。仿真实验结果表明,该算法与以前的量化算法相比提高了水印的透明性,并对高斯噪声、中值滤波、JPEG压缩等常见攻击具有更强的鲁棒性。To increase the invisibility and robustness, a digital watermarking algorithm based on DWT domain is combined with μ -law technology and logarithmic quantization index modulation. The algorithm has solved the problem of not being applicable to non-uniform signal for QIM uniform quantization. The original image is conducted with discrete wavelet transform. Then the fji -law func tion is appl ied to the approximate part coefficients of the or iginal image. The transformed signal is quantized to embed binary watermark data by using QIM. The watermark embedding position, quantization step and parameters are discussed to obtain optimum values in this paper. Experimental results show that this algorithm improves invisibility of the watermark. Moreover, the proposed scheme has strong robustness against common attacks, such as Gaussian noise, median filtering, JPEG compression.

关 键 词：离散小波变换 μ律函数 对数量化 量化索引调制 数字水印 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]