期刊名称：Archiwum Fotogrametrii, Kartografii i Teledetekcji
印刷版ISSN：2083-2214
出版年度：2014
卷号：26
DOI：10.14681/afkit.2014.001
语种：English
出版社：Main Board of Association of Polish Surveyors
摘要：The presented research concerns methods related to reduction of elevation data contained in digital terrain model (DTM) from airborne laser scanning (ALS) in hydraulic modelling. The reduction is necessary in the preparation of large datasets of geospatial data describing terrain relief. Its course should not be associated with regular data filtering,which often occurs in practice. Such a method leads to a number of important forms important for hydraulic modeling being missed. One of the proposed solutions for the reduction of elevation data contained in DTM is to change the regular grid into the hybrid structure with regularly distributed points and irregularly located critical points. The purpose of this paper is to compare algorithms for extracting these key points from DTM. They are used in hybrid model generation as a part of elevation data reduction process that retains DTM accuracy and reduces the size of output files. In experiments,the following algorithms were tested: Topographic Position Index (TPI),Very Important Points (VIP) and Z-tolerance. Their effectiveness in reduction (maintaining the accuracy and reducing datasets) was evaluated in respect to input DTM from ALS. The best results were obtained for the Z-tolerance algorithm,but they do not diminish the capabilities of the other two algorithms: VIP and TPI which can generalize DTM quite well. The results confirm the possibility of obtaining a high degree of reduction reaching only a few percent of the input data with a relatively low decrease of vertical DTM accuracy to a few centimetres. The presented paper was financed by the Foundation for Polish Science - research grant no. VENTURES/2012-9/1 from Innovative Economy program of the European Structural Funds.
其他摘要：Przedstawione badania dotyczą opracowania algorytmu redukcji ilości danych wysokościowych w postaci numerycznego modelu terenu z lotniczego skanowania laserowego (ALS) dla potrzeb modelowania powodziowego. Redukcja jest procesem niezbędnym w przetwarzaniu
关键词：Digital Terrain Model;critical points;data redu
其他关键词：numeryczny model terenu;punkty istotne;redukcja ilościowa danych; generalizacja;indeks pozycji topograficznej (TPI);Very Important Points (VIP);Z-tolerance
