Classification of LiDAR point clouds in urban areas based on the analysis of regional multi-return density
LI Lelin1, JIANG Wanshou2, GUO Chengfang3
1. National-Local Joint Engineering Laboratory of Geo-Spatial Information Technology, Hunan University of Science and Technology, Xiangtan 411201, China;
2. State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430079, China;
3. Architectural Institute of Technology, Liuzhou Railway Vocational Technical College, Liuzhou 545007, China
A new strategy for the classification of raw LiDAR points in urban areas, which is based on the comprehensive utilization of echo features of different object types and terrain information, is proposed in this paper according to a regional multi-return density analysis. The main procedure of the classification of the off-terrain points begins with the construction of Triangulated Irregular Network (TIN), and then the region of each object is captured by the contours clustering based on the topological relations of various contours traced from the TIN. Finally, the type of the object is recognized by the statistical analysis of the regional multi-return density through the significant difference between the building region and the vegetation region. This method not only makes good use of the difference in echo features between different objects such as buildings and trees but also confirms the existence of the multi-returns on the edges of the building. At the same time, the adaptive region determination of the objects is accomplished following the contours clustering. So the proposed method can dramatically increase the classification accuracy and overcome the weakness of the traditional methods, thus being more useful to the study and application of such aspects as building reconstruction and parameters estimation of the trees. Experiments prove that the new algorithm can get an effective classification.
李乐林, 江万寿, 郭程方. 基于区域多次回波点密度分析的城区LiDAR建筑物提取[J]. 国土资源遥感, 2015, 27(2): 29-35.
LI Lelin, JIANG Wanshou, GUO Chengfang. Classification of LiDAR point clouds in urban areas based on the analysis of regional multi-return density. REMOTE SENSING FOR LAND & RESOURCES, 2015, 27(2): 29-35.
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2015, Vol. 27 
