基于BKF矢量HMT的非下采样剪切波域数字水印检测算法  

A Blind Watermark Decoder in NSST Domain Using BKF Vector HMT Model

作　　者：王向阳[1] 牛盼盼[1] 田静 杨红颖[1] 徐欢 WANG Xiang-yang;NIU Pan-pan;TIAN Jing;YANG Hong-ying;XU Huan(School of Computer and Information Technology,Liaoning Normal University,Dalian,Liaoning 116029,China)

机构地区：[1]辽宁师范大学计算机与信息技术学院,辽宁大连116029

出　　处：《电子学报》2021年第1期40-49,共10页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61472171,No.61701212);辽宁省教育厅科学研究经费项目(重点项目)(No.LZ2019001);辽宁省自然科学基金(No.2019-ZD-0468)。

摘　　要：以非下采样剪切波变换(NSST)及隐马尔可夫树(HMT)理论为基础,提出了一种基于BKF(Bessel K Form)矢量HMT的非下采样剪切波域图像水印算法.水印嵌入时,首先对原始载体图像进行NSST;然后构造自适应高阶水印嵌入强度函数;最后选择重要的NSST高频系数乘性嵌入水印.水印检测时,首先根据NSST系数的非高斯分布特性及NSST系数间的子带内、方向间、尺度间等多种相关特性,建立具有强描述能力的BKF矢量HMT模型;然后利用最大期望(EM)方法,估计出BKF矢量HMT模型参数;最后结合BKF矢量HMT模型和最大似然(ML)检验理论,构造出数字水印检测器并提取水印.仿真实验结果证明了本文算法的有效性.In this paper,we propose a blind NSST domain image watermark decoder,wherein a vector-based HMT statistical model using BKF distribution is used.In the proposed scheme,the NSST is firstly performed on the original host image,and then the adaptive high-order watermark embedding strength functions are constructed,and finally the watermark data is embedded into the significant high-frequency coefficients in NSST domain.At the watermark receiver,NSST highpass coefficients are firstly modeled by employing the BKF vector HMT,where the BKF marginal statistics and strong intra-subband,cross-scale,and cross-orientation dependencies of NSST coefficients are incorporated.Then the statistical model parameters of BKF vector HMT are estimated using the expectation maximization approach.And finally a blind image watermark decoder is developed using BKF vector HMT and the maximum likelihood decision rule.The experimental results validate the effectiveness of the proposed technique.

关 键 词：图像水印 矢量HMT BKF分布 非下采样剪切波变换 自适应嵌入强度 最大似然决策 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]