摘要： 在文物碎片自动拼接中,由于断裂部位受损造成几何特征缺失,传统基于几何驱动拼接算法难以拼合。为此,提出一种基于断裂部位轮廓线双向距离场的文物碎片自动拼接算法。通过提取文物碎片表面的显示脊线,从而得到碎片的纹饰特征,采用最小逼近误差法提取表面纹饰轮廓上的特征点,依据顶点曲度值获取断裂面特征点,构建碎片断裂面轮廓线至表面特征点和断裂面特征点的双向距离场,引入欧式距离一致性和凹凸互补性的约束,构造特征描述符,定义匹配度函数获取特征点匹配对集合,使用四元数算法计算刚体变换矩阵,以迭代最近点法实现精确拼合。实验结果表明,与传统断裂面拼接算法相比,该算法能节省拼合时间,且拼合误差较小。

关键词: 距离场, 显示脊线, 最小逼近误差法, 四元数, 迭代最近点

Abstract: In the automatic reassembly of cultural fragments,because of the loss of the geometric characteristics caused by the damage of the fractured faces,an automatic reassembly algorithm based on the two-way distance field of the break-curves is proposed.Through the extraction of apparent ridges of fragments surface,so as to get the sculpture structure,using the minimum approximation error method to extract feature points on the contour surface decoration,on the basis of the vertex curvature value acquiring feature points of fractured faces,construction of bidirectional distance field fracture profile feature points to the surface and fracture surface feature points,the introduction of Euclidean distance from the consistency and complementarity of convex constraints,structuring feature descriptors,defining matching degree function to obtain the feature points matching set,and using quaternions algorithm to calculate the rigid transform matrix,the iterative closest point method to achieve accurate registration.Experimental results show that compared with the traditional splicing algorithm,the algorithm can save reassembly time and reduce the errors.

Key words: distance field, display ridge line, minimum approximation error method, quaternion, iterative nearest point

中图分类号: 

• TP391