基于DCT-DQFT变换和QR分解的彩色图像盲水印算法  

Blind Watermarking Algorithm of Color Images Based on DCT-DQFT and QR Decomposition

作　　者：马玲[1] 覃亮成 MA Ling;QIN Liangcheng(School of Information and Electronics,Beijing Institute of Technology,Beijing 100080,China;College of Electronic Science and Technology,National University of Defense Technology,Changsha 410073,China)

机构地区：[1]北京理工大学信息与电子学院,北京100080 [2]国防科技大学电子科学学院,长沙410073

出　　处：《信息网络安全》2021年第9期25-31,共7页Netinfo Security

摘　　要：为了提高彩色图像数字水印的性能,同时兼顾彩色图像3个颜色通道之间的相关性,文章提出了一种基于DCT变换和DQFT变换的QR矩阵分解水印嵌入算法,融合了变换域水印算法较好的鲁棒性,能将彩色图像三通道作为整体处理来嵌入水印信息。首先,对彩色图像RGB三通道分别进行DCT变换,选取变换后的3个1/4中低频分量作为四元数矩阵的3个虚部构造一个纯四元数矩阵Q,对Q进行DQFT变换,选取变换后的实部进行4×4分块,对每个数据块做QR分解后嵌入水印信息。实验结果表明,面对噪声攻击、JPEG压缩、中值滤波等攻击时,文章提出的水印算法具有良好的鲁棒性。In order to improve the performance of color image digital watermark and take into account the correlation between three color channels of color image,a QR matrix decomposition watermark embedding algorithm based on discrete cosine transform(DCT)and discrete quaternion Fourier transform(DQFT)was proposed,which integrated the good robustness of watermark algorithm based on transform domain and could embed watermark information by processing the three channels of color image as a whole.Firstly,the three RGB channels of the color image were discrete cosine transformed respectively,and the transformed three 1/4 medium and low frequency components were selected as the three imaginary parts of the quaternion matrix to construct a pure quaternion matrix Q.The Q was discrete quaternion Fourier transformed,and the transformed real part was selected for 4×4 blocks,the data of which was QR decomposed and the watermark information was embedded.Experimental results show that the proposed watermarking algorithm is robust to noise attacks,JPEG compression,median filtering and other attacks.

关 键 词：DCT 四元数 DQFT QR分解 盲水印 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]