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...ath 2005). At this stage, the terrain is uniformly normalized and the separation between on- and off-terrain points is applicable. The building boundary is determined by a modified convex hull algorithm (Jarvis 1973) which classifies the cluster data into boundary (contour/edge) and non-boundary (intershape) points (Jarvis 1977). Separating points located on buildings from those on trees and bushes, is a difficult task (Wang & Shan 2009). The common assumption is that the building outlines are separated from the trees in terms of size and shape. The dimensionality learning method, proposed by Wang and Shan (2009), is an efficient technique for this purpose. In relatively flat urban areas, the roads, which have the same elevation (height) as a bare surface, can be extracted by arrangement examination. The simple geometric and topological relations between streets might be used to improve the consistency of road extraction. First, the DEM data are used to obtain candidate roads, sidewalks and parking lots. Then the road model is established, based on the continuous network of points which are used to extract information such as centerline, edge and width of the road (Akel et al. 2003; Hinz & Baumgartner...

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... to extract basic geometric shapes from the data [71]. Patch-type methods strive to segment the data into homogeneous regions based on similarities between local points or the proximity of the points =-=[88]-=-. The segmentation of the human body scans falls into the 2-1 Figure 2. An example of the use of a LiDAR system to map terrain. The LiDAR transmits a light pulse which is reflected back to the receive...

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...al Terrain Models (DTM) and fused with the optical images (Rottensteiner et al., 2004),(Sohn and Dowman, 2007). However, this leads to loss of the rich geometrical information inherent to LiDAR data (=-=Wang and Shan, 2009-=-). Very few studies have attempted using the coloured point cloud for urban scene analysis (Niemeyer et al., 2014). Assigning labels to each points in the dataset can be either point based or object b...