提出一种基于分层等值线的地面激光扫描(TLS)数据表面重建及多分辨率表达方法.依据迭代的凸包算法,在具有垂直分布特点的点云中提取分层等值线.采用同步前进的最小外接圆方法完成分层等值线之间的三角剖分,得到地物局部三角形带.连接分层的局部三角形带并统一法线向量,得到地物整体三角网模型.采用等值线的高程间距和水平采样间隔作为控制参数,探讨了参数优化配置方法,实现地物整体模型的多分辨率表达.最后通过两个实例验证了本文方法的可行性.
A stratified contours based surface reconstruction and multi-resolution express method is proposed in this paper.First,an iterated convex hull algorithm is hired to extract the stratified contours from vertical distributed point cloud.Then,based on the stratified contours,in synchronous headway premise,the shortest circumcircle radius method is adopted to finish the triangularization processing from adjacent contours to obtain the local object's model.After connecting the triangles in adjacent levels and unifying the normal vector for each triangle,the reconstructed surface model could be used to express the object.To convey the surface model in multi-resolution,the elevation interval and horizontal resample distance is chosen as the model parameters for low resolution model generation.Furthmore,the optical parameter selection method is introduced to achieve better modeling results.At last,two case studies are chosen to verify the validity of the proposed method.