Wedge-Filtering of Geomorphologic Terrestrial Laser Scan Data

Terrestrial laser scanning is of increasing importance for surveying and hazard assessments. Digital terrain models are generated using the resultant data to analyze surface processes. In order to determine the terrain surface as precisely as possible, it is often necessary to filter out points that...

Full description

Bibliographic Details
Main Authors: Alexander Prokop, Helmut Panholzer
Format: Article
Language:English
Published: MDPI AG 2013-02-01
Series:Sensors
Subjects:
Online Access:http://www.mdpi.com/1424-8220/13/2/2579
_version_ 1818038447811592192
author Alexander Prokop
Helmut Panholzer
author_facet Alexander Prokop
Helmut Panholzer
author_sort Alexander Prokop
collection DOAJ
description Terrestrial laser scanning is of increasing importance for surveying and hazard assessments. Digital terrain models are generated using the resultant data to analyze surface processes. In order to determine the terrain surface as precisely as possible, it is often necessary to filter out points that do not represent the terrain surface. Examples are vegetation, vehicles, and animals. Filtering in mountainous terrain is more difficult than in other topography types. Here, existing automatic filtering solutions are not acceptable, because they are usually designed for airborne scan data. The present article describes a method specifically suitable for filtering terrestrial laser scanning data. This method is based on the direct line of sight between the scanner and the measured point and the assumption that no other surface point can be located in the area above this connection line. This assumption is only true for terrestrial laser data, but not for airborne data. We present a comparison of the wedge filtering to a modified inverse distance filtering method (IDWMO) filtered point cloud data. Both methods use manually filtered surfaces as reference. The comparison shows that the mean error and root–mean-square-error (RSME) between the results and the manually filtered surface of the two methods are similar. A significantly higher number of points of the terrain surface could be preserved, however, using the wedge-filtering approach. Therefore, we suggest that wedge-filtering should be integrated as a further parameter into already existing filtering processes, but is not suited as a standalone solution so far.
first_indexed 2024-12-10T07:42:53Z
format Article
id doaj.art-ef49626b8f31437f87abdd14c3a355dd
institution Directory Open Access Journal
issn 1424-8220
language English
last_indexed 2024-12-10T07:42:53Z
publishDate 2013-02-01
publisher MDPI AG
record_format Article
series Sensors
spelling doaj.art-ef49626b8f31437f87abdd14c3a355dd2022-12-22T01:57:15ZengMDPI AGSensors1424-82202013-02-011322579259410.3390/s130202579Wedge-Filtering of Geomorphologic Terrestrial Laser Scan DataAlexander ProkopHelmut PanholzerTerrestrial laser scanning is of increasing importance for surveying and hazard assessments. Digital terrain models are generated using the resultant data to analyze surface processes. In order to determine the terrain surface as precisely as possible, it is often necessary to filter out points that do not represent the terrain surface. Examples are vegetation, vehicles, and animals. Filtering in mountainous terrain is more difficult than in other topography types. Here, existing automatic filtering solutions are not acceptable, because they are usually designed for airborne scan data. The present article describes a method specifically suitable for filtering terrestrial laser scanning data. This method is based on the direct line of sight between the scanner and the measured point and the assumption that no other surface point can be located in the area above this connection line. This assumption is only true for terrestrial laser data, but not for airborne data. We present a comparison of the wedge filtering to a modified inverse distance filtering method (IDWMO) filtered point cloud data. Both methods use manually filtered surfaces as reference. The comparison shows that the mean error and root–mean-square-error (RSME) between the results and the manually filtered surface of the two methods are similar. A significantly higher number of points of the terrain surface could be preserved, however, using the wedge-filtering approach. Therefore, we suggest that wedge-filtering should be integrated as a further parameter into already existing filtering processes, but is not suited as a standalone solution so far.http://www.mdpi.com/1424-8220/13/2/2579terrestrial laser scanningfilteringwedge
spellingShingle Alexander Prokop
Helmut Panholzer
Wedge-Filtering of Geomorphologic Terrestrial Laser Scan Data
Sensors
terrestrial laser scanning
filtering
wedge
title Wedge-Filtering of Geomorphologic Terrestrial Laser Scan Data
title_full Wedge-Filtering of Geomorphologic Terrestrial Laser Scan Data
title_fullStr Wedge-Filtering of Geomorphologic Terrestrial Laser Scan Data
title_full_unstemmed Wedge-Filtering of Geomorphologic Terrestrial Laser Scan Data
title_short Wedge-Filtering of Geomorphologic Terrestrial Laser Scan Data
title_sort wedge filtering of geomorphologic terrestrial laser scan data
topic terrestrial laser scanning
filtering
wedge
url http://www.mdpi.com/1424-8220/13/2/2579
work_keys_str_mv AT alexanderprokop wedgefilteringofgeomorphologicterrestriallaserscandata
AT helmutpanholzer wedgefilteringofgeomorphologicterrestriallaserscandata