期刊名称:ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN:2194-9042
电子版ISSN:2194-9050
出版年度:2010
卷号:XXXVIII Part 4
出版社:Copernicus Publications
摘要:There are two challenges in classifying lidar points into ground and non-ground points on Texas coastal areas, which usually hasa low-lying landform consisting of morphological features including dunes, tidal and river channels with levees, barren flats,buildings, and trees with varying cover density. The first is to remove buildings and trees meanwhile keeping seawall, dunes,levees and channels. The second is to remove bushes and grasses. In this paper, a novel classification approach based on slopeand neighbor properties is designed to meet these challenges. The innovation of this approach is to first determine the mostsuitable post-spacing for a given lidar point dataset and then to generate a raster with the post-spacing. Slope thresholds forlandscape objects, such as buildings and trees, are derived from their own characteristic size. The classification has three mainsteps. Step 1 – identifying potential areas by removing steep slope cells. The slope calculation and removal are repeated severaltimes. This step may incorrectly create holes. Step 2– restoring holes: the lidar points falling in a potential area are identified intotwo classes: the correctly removed or not. The latter are restored. Step 3– identifying bushes and grasses based on slope.Classifications have been carried out with a lidar point dataset of Mustang Island, Texas (a 40-km long barrier island) withpromising results