基于BEMD与DCT的彩色图像多重水印鲁棒算法  

Robust multiple watermarking algorithm for color image via BEMD and DCT

作　　者：胡坤 李聪[4] 胡建平 王小超[6] 杜玲 王红飞 HU Kun;LI Cong;HU Jianping;WANG Xiaochao;DU Ling;WANG Hongfei(University of Chinese Academy Sciences,Beijing 100049,China;Key Laboratory of Space Utilization,Chinese Academy of Sciences,Beijing 100094,China;Technology and Engineering Center for Space Utilization,Chinese Academy of Sciences,Beijing 100094,China;School of System Science,Beijing Normal University,Beijing 100875,China;School of Science,Northeast Electric Power University,Jilin 132012,China;School of Mathematical Sciences,Tiangong University,Tianjin 300387,China;School of Computer Science and Technology,Tiangong University,Tianjin 300387,China)

机构地区：[1]中国科学院大学,北京100049 [2]中国科学院太空应用重点实验室,北京100094 [3]中国科学院空间应用工程与技术中心,北京100094 [4]北京师范大学系统科学学院,北京100875 [5]东北电力大学理学院,吉林132012 [6]天津工业大学数学科学学院,天津300387 [7]天津工业大学计算机科学与技术学院,天津300387

出　　处：《北京航空航天大学学报》2023年第1期165-176,共12页Journal of Beijing University of Aeronautics and Astronautics

基　　金：天津市高等学校基本科研业务费(2018KJ222);北京航空航天大学虚拟现实技术与系统国家重点实验室开放基金(BUAA-VR-16KF-23,BUAA-VR-17KF-04)。

摘　　要：为解决现有彩色图像水印算法容错性低及宿主图像与水印图像在嵌入时尺寸匹配问题,并提高算法抵御各种攻击的鲁棒性,提出一种基于二维经验模态分解(BEMD)和离散余弦变换(DCT)的彩色图像多重水印鲁棒算法。使用Arnold变换对3幅二值水印图像进行置乱,分别对彩色宿主图像的三通道进行BEMD,得到各通道的内蕴模态函数(IMF)和余量信息,选择各通道的第1个IMF(记作IMF_(1))作为水印嵌入层,对每个通道的IMF_(1)分割成不重叠子块后进行DCT;再将置乱后的二值水印图像依次重复嵌入在各通道子块经过之字形(Zigzag)扫描后的中频系数中,使用逆Zigzag扫描和逆DCT得到各通道嵌入水印信息后的IMF_(1),并与每个通道其余的IMF及余量重建得到嵌入水印后的彩色图像。水印提取为嵌入过程的逆过程,算法可以实现彩色图像嵌入水印的盲提取。在水印提取过程中对重复嵌入提取到的水印图像使用投票策略,增强了算法的容错性。大量实验结果表明:嵌入水印后的图像峰值信噪比(PSNR)在34 dB以上,水印信息具有较高的不可见性;对嵌入多重水印后的宿主图像进行大尺寸剪切、椒盐噪声等攻击实验,提取到的水印图像与原始图像的归一化系数均在0.96以上,且可达到1,水印信息提取完整清晰可辨。与现有大量彩色图像水印算法相比,所提算法具有较强抵御各种攻击的能力,同时嵌入水印后图像具有较高的不可见性。In order to solve the problem that the color image watermarking algorithm has low algorithm fault tolerance,and the size matching problem between the host image and the watermark image during embedding,and to improve the robustness of the algorithm in attack resistance,this paper proposes a robust multiple water-marking algorithm for color images based on bi-dimensional empirical mode decomposition(BEMD)and discrete cosine transform(DCT).Firstly,Arnold transform is used to scramble three binary watermark images.Then,the RGB channels of the color host image are then decomposed using BEMD in addition to derive the intrinsic modal functions(IMFs)and residues for each channel.The first IMF of each channel is selected as the watermark embedding layer and recorded as IMF_(1).After that,each channel is divided into non-overlapping sub-blocks,and DCT is performed on each sub-blocks.Finally,the scrambled binary watermark image is repeatedly embedded in the middle bands coefficients of each channel sub-block after a Zigzag scan,and the inverse Zigzag scan and inverse DCT are adopted to obtain the IMF_(1) after embedding watermark information in each channel,and then the remaining intrinsic modal functions and residues of each channel are used to reconstruct the color image after the watermark embedding.The watermark extraction is the inverse of the watermark embedding process.The algorithm in this paper can implement blind extraction of embedded watermarks.In the process of watermark extraction,the voting strategy is used to extract the repeatedly embedded watermarks,which enhances the fault tolerance of the algorithm.A large number of experimental results show that the peak signal-to-noise ratio(PSNR)of the host images is above 34 dB after several watermarks have been embedded on various sets of host photos,according to a vast number of experimental results,and the watermark images have a high degree of invisibility.The host images after embedding can be against various attacks such as large-scale cropping,salt and pepper

关 键 词：二维经验模态分解 多重数字水印 离散余弦变换 伪随机序列 彩色图像 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]