Bare-earth extraction and DTM generation from photogrammetric point clouds including the use of an existing lower-resolution DTM

作     者：Debella-Gilo, Misganu 

作者机构：Norwegian Inst Bioecon Res NIBIO Mapping & Stat Div Dept Geomat POB 115 N-1431 As Norway 

出 版 物：《INTERNATIONAL JOURNAL OF REMOTE SENSING》 (国际遥感杂志)

年 卷 期：2016年第37卷第13期

页      面：3104-3124页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 1002[医学-临床医学] 08[工学] 09[农学] 0804[工学-仪器科学与技术] 0903[农学-农业资源与环境] 0816[工学-测绘科学与技术] 081602[工学-摄影测量与遥感] 081102[工学-检测技术与自动化装置] 0811[工学-控制科学与工程] 

基　　金：Norwegian Institute of Bioeconomy Research (NIBIO) 

主　　题：DATA extraction DIGITAL elevation models PHOTOGRAMMETRY INTERPOLATION algorithms FOREST canopies TERRAIN mapping 

摘      要：A method of extracting bare-earth points from photogrammetric point clouds by partially using an existing lower resolution digital terrain model (DTM) is presented. The bare-earth points are extracted based on a threshold defined by local slope. The local slope is estimated from the lower resolution DTM. A gridded DTM is then interpolated from the extracted bare-earth points. Five different interpolation algorithms are implemented and evaluated to identify the most suitable interpolation method for such non-uniformly scattered data. The algorithm is tested on four test sites with varying topographic and ground cover characteristics. The results are evaluated against a reference DTM created using aerial laser scanning. The deviations of the extracted bare-earth points, and the interpolated DTM, from the reference DTM increases with increasing forest canopy density and terrain roughness. The DTM created by the method is significantly closer to the reference DTM than the lower resolution national DTM. The ANUDEM (Australian National University Digital Elevation Modelling) interpolation method is found to be the best performing interpolation method in terms of reducing the deviations and in terms of modelling the terrain realistically with minimum artefacts, although the differences among the interpolation methods are not considerably large.