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：2007
卷号：XXXVI-3/W52
页码：20-25
出版社：Copernicus Publications
摘要：Nowadays orthophotos from satellite and aerial imagery are very requested products, considering their low cost motivated by the highly automated production chain. The generation of orthophotos requires a block of oriented images and a digital model of the ground (DTM or DSM). In case a DTM is adopted, the lackness of information about buildings results in distortions. The availability of a LiDAR DDSM allows to overcome this problem, even though if the spatial resolution is not very high, some problems in correspondence of building contour might arise. To solve for this drawback, a method based on thickening a LiDAR DDSM from an initial grid of 2×2 m2 to a 0.2×0.2 m2 one is proposed here. This method has been implemented by exploiting the availability of a spatial DB of the same area, which allows to classify all points of the thickened DDSM in two categories: those belonging to a building and those not. A test of the method has been carried out on a photogrammetric block taken over the town of Lecco (Northern Italy) by a RC30 Wild camera at 1:17,000 mean scale, and afterward digitized by scanning. The LiDAR DDSM adopted has been provided by Lombardia Region at a spatial resolution of 2×2 m2. The thickening of the DSM has been performed using a building mask extracted from the new spatial DB of Lecco. Orthophotos created in this manner take advantage of the whole cartographic and spatial material already available at the Public Administration Department, and presents an improved accuracy than a classic orthophoto with a computation time approximately equal
