任帅 徐振超 王震 贺媛 张弢 苏东旭 慕德俊

摘 要：针对现有三维模型信息隐藏算法无法有效抵抗不均匀压缩的问题，提出一种基于多融合态的多载体低密度的信息隐藏算法。首先通过平移和缩放对多个三维模型进行定位、定向及定型;其次对三维模型进行不同角度的旋转，以中心点作为融合点进行融合，得到多个融合态;再次，利用局部高度和Mean Shift聚类分析算法对融合态模型的顶点进行能量划分，得到不同能量的顶点;最后，通过修改顶点坐标的方法将经过Arnold置乱变化的秘密信息快速隐藏于多个融合态和三维模型中。实验结果表明，该算法对抵御不均匀压缩的攻击有很好的鲁棒性且具有很高的不可见性。

关键词：信息隐藏;三维模型;融合态;局部高度理论;Mean Shift聚类分析

中图分类号：TP309.2;TP301.6

文献标志码：A

文章编号：1001-9081（2019）04-1100-06

Abstract： Aiming at the problem that the existing 3D model information hiding algorithms cannot effectively resist uneven compression， a multi-carrier low-density information hiding algorithm based on multiple fusion states was proposed. Firstly， multiple 3D models were positioned， oriented and stereotyped by translation and scaling. Secondly， the 3D models were rotated at different angles and merged by using the center point as merging point to obtain multiple fusion states. Thirdly， local height and Mean Shift clustering analysis were used to divide the energy of the vertices of the fusion state model， obtaining the vertices with different energies. Finally， by changing the vertex coordinates， the secret information changed by Arnold scrambling was quickly hidden in multiple fusion states and 3D models. Experimental results show that the proposed algorithm is robust against uneven compression attacks and has high invisibility.

Key words： information hiding; 3D model; fusion state; local height theory; Mean Shift clustering analysis

0 引言

三維模型的信息隐藏技术是当今信息隐藏安全领域中的一个研究热点。目前，基于三维模型的信息隐藏技术的研究主要是基于空间域和变换域的。文献[1]首先以协方差分析得到三维模型的初始特征点为核心，在它的K近邻域中构建不跨越区域最小三角形为嵌入单元的底面;其次将剩余顶点按照升序排序，寻找合适的嵌入顶点;最后通过改变顶点信息来嵌入水印。文献[2]通过计算模型的重心，利用顶点和重心连线与模型求交的方法计算出重心交点距离比，并通过修改三角形面片3个顶点对应的重心点距离比（Ratio of Barycenter and Crosspoint， RBC）来嵌入信息。……