an alpha value (0< α < ∞) is a parameter imposing the precision of the final boundary. A large value(α->∞) results in the alpha boundary of a convex hull while a small value (α->0) means that every point can be the boundary point. 暴力思想: 预定义圆的半径r,遍历点集P内的任...
// BigInteger b = new BigInteger(1, sha1.digest()); // System.out.println("sha1 (Generated by Java built-in algorithm): " + b.toString(16)); } } class SHA1 { static String generate(byte[] dataBytes) throws Exception { byte[] fillBytes = new byte[64 * ((dataBytes.length + ...
The registered point cloud was triangulated using the Alpha-shape algorithm to achieve surface reconstruction. The above-mentioned methods of initial registration and precise registration were used to globally register multiple jujube trees and completely reconstruct the three-dimensional model...
surface reconstruction;Alpha shape;average distance of k-nearest neighbors;Alpha—shapealgorithm引 言三维物体表面重建是获取三维空间信息建立该物体的三维模型,在3D城市、3D游戏等场景建模有着重要应用[11;在林业信息化测量中,利用重建的树冠形状,准确求解树冠体积、表面积和占地面积等信基金项目:国家自然科学基金(...
algorithm.h> typedef CGAL::Exact_predicates_inexact_constructions_kernel K; typedef K::FT FT; typedef K::Point_2 Point; typedef K::Segment_2 Segment; typedef CGAL::Alpha_shape_vertex_base_2<K> Vb; typedef CGAL::Alpha_shape_face_base_2<K> Fb; typedef CGAL::Triangulation_data_structure_...
Second, they are more robust to noise and outliers, as they do not require all points to be on the boundary of the shape. Third, they can be computed efficiently using theDelaunay triangulation, which is a well-known and widely used algorithm. Alpha shapes have been used in a variety of...
Alpha shapes provide a more flexible approach to shape analysis, allowing for concave boundaries as well as convex ones. The resulting shape can be simpler and more informative than other methods of boundary extraction,particularly when dealing with complex shapes. The alpha shape algorithm works by...
分段线性简单曲线。AlphaShape最早在1981年被构想出来,随后它被应用与 多种科学与工程领域,其中包括模式识别,数字采样和处理,结构分子生物学等 等。 Alpha-Shapes可以用来从一堆无序的点集中提取边缘。设有一点集s的 Alpha-Shapes是一个多边形,这个多边形是由点集s和半径参数α决定的且唯 ...
图2 Alpha⁃shape算法效果图 Fig.2 EffectdiagramofAlpha⁃shapealgorithm α 观察表面重建效果图后发现,在中间“把手”和底部交接的部分,由于过大的 值,使得表面三角形 偏大,其重建效果过于粗糙,不能很好地体现物体原有的表面凹凸信息,如图2(e)所示;同时,过大的α 值导致在处理密度较大的底部区域时需要遍历...
The registered point cloud was triangulated using the Alpha-shape algorithm to achieve surface reconstruction. The above-mentioned methods of initial registration and precise registration were used to globally register multiple jujube trees and completely reconstruct the three-dimensional model of fruit ...