Print Email Facebook Twitter 3D breakline extraction from point clouds with the Medial Axis Transform Title 3D breakline extraction from point clouds with the Medial Axis Transform Author Wang, Qu (TU Delft Architecture and the Built Environment) Contributor Peters, R.Y. (mentor) Ledoux, H. (graduation committee) Degree granting institution Delft University of Technology Programme Geomatics Date 2019-06-09 Abstract This project develop a new method to generate breakline from the point cloud directly with the MAT. The breakline is a structured line of the object surface which has high curvature. Meanwhile, the reciprocal of the medial edge ball's radius can represent the point with high curvature, which is the fundamental idea of this project. The key parts of the method are: (a) with the help of MAT detecting candidate points having high curvature; (b) connect the candidate points to get breaklines with graph theory or polynomial fitting. The topology of the breakline is considered. In addition, this project also provides the polyline simplification and smoothing. In the resulting breakline, 27/32 are true positive. In general, the average correctness is 97% and 96%, the average quality is 90.67% and 91.19%, and the average completeness is 93.84% and 93.92% for valley and ridge. Most of accuracy parameters are above 80%. The accuracy is high. As to the precision, the average polyline precision is 0.3 and 0.23, and the average vertex precision is 1.14 meter and 1.12 meter. Comparing with the point density 2 pts/m^2. 25 of 27 breaklines' polyline precision is better than 0.5. 16 of 27 breakline's vertex precision is better than 1.0; and 23 of 26 is better than 1.5. The precision is also good. The source code is on Github: https://github.com/qq2012/geoflow-nodes. Subject breaklinemountainMedial Axis Transformpoint cloud To reference this document use: http://resolver.tudelft.nl/uuid:ba8e4bf4-e473-410b-a1f0-ef48e9c2fbf3 Part of collection Student theses Document type master thesis Rights © 2019 Qu Wang Files PDF p5_QuWang_thesis.pdf 57.84 MB PDF p5_QuWang_presentation.pdf 6.95 MB Close viewer /islandora/object/uuid:ba8e4bf4-e473-410b-a1f0-ef48e9c2fbf3/datastream/OBJ1/view