基于联合α熵的三维耳廓形状匹配
3D Ear Shape Matching Using Joint α-Entropy
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摘要: 本文将三维耳廓的局部形状特征嵌入联合α熵,从而实现了三维耳廓形状匹配.首先,本文从三维耳廓点云中提取足够数目的局部关键点,并将关键点邻域在乘积型参数域上拟合为单值的二次曲面;然后,对二次曲面上的参数节点进行深度采用,定义每个关键点上的局部显著特征;第三,对于数据库中的所有耳廓,基于其与待匹配耳廓之间关键点匹配关系,构建最小生成树;最后,通过优化最小生树的边权,使其取得最小值,得到最小生成树的联合α熵,拥有最小联合α熵的匹配对,即为最为相似的耳廓对.本文首先将传统信息论中的联合α熵应用于三维耳廓形状匹配,诸多实验结果证明了本文算法具有较好的时间复杂度、较高的识别率和健壮性.Abstract: In this article, we investigate the use of joint α-entropy for 3D ear matching by incorporating local shape feature of 3D ears into the joint α-entropy. First, we extract a sufficient number of key points from the 3D ear point cloud, and fit the neighborhood of each key point to a single-value quadric surface on product parameter regions. Second, we define the local shape feature vector of each key point as the sampling depth set on the parametric node of the quadric surface. Third, for every pair of gallery ear and probe ear, we construct the Minimum Spanning Tree (MST) on their matched key points. Finally, we minimize the total edge weight of MST to estimate its joint α-entropy—the smaller the entropy is, the more similar the ear pair is. We present several examples to demonstrate the advantages of our algorithm, including low time complexity, high recognition rate and high robustness. Furthermore, we demonstrate, for the first time in computer graphics, the classical information theory of joint α-entropy is used to deal with 3D ear shape recognition.