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：2004
卷号：XXXV Part B3
页码：237-242
出版社：Copernicus Publications
摘要：This paper describes the height and planimetric errors of repeated ALS (airborne laser scanning) strips with a deeper focus on building extraction. Measurements with Toposys Falcon airborne laser scanner were arranged in May 2003 in Espoo, Southern Finland. A 5 km 2 test area, consisting of urban settlements and forests, were collected from the altitude of 400 m resulting in measurement density of about 10 points per square metre. One 4 km long and about 100 m wide strip was collected five times allowing the analysis of the repeatability of the laser scanning. One strip was used as a reference and inter-strip comparisons were made. Point wise comparison methods were also used to characterize the differences. Additionally, target models were compared against each other. Real Time Kinematic (RTK) GPS and also tachymeter measurements were used as ground reference. Extraction of building vectors from laser scanner data was performed using interactive methods implemented in the TerraScan software. The accuracy of the vectorization is also reported. Mean height errors for elevation points were –2 to 1 cm and standard deviations were mainly ±3-4 cm. In planimetry, mean errors of the centre points of the buildings were less than 30 cm for the first and also for the last pulse data when compared with the buildings on the map. The standard deviations varied between ±11-28 cm (first pulse) and ±14- 18 cm (last pulse) for extracted buildings using repeated observations. Mean errors were between 3-8 cm and standard deviations ±3- 6 cm using last pulse data of repeated observations and extracted ridge information. Extracted buildings were systematically larger from first pulse data than from last pulse data
