Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest Inventory

This paper presents a fully automatic method addressing tree mapping and parameter extraction (tree position, stem diameter at breast height, stem curve, and tree height) from terrestrial laser scans in forest inventories. The algorithm is designed to detect trees of various sizes and architectures,...

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Main Authors: Gábor Brolly, Géza Király, Matti Lehtomäki, Xinlian Liang
Format: Article
Language:English
Published: MDPI AG 2021-02-01
Series:Remote Sensing
Subjects:
Online Access:https://www.mdpi.com/2072-4292/13/4/542
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author Gábor Brolly
Géza Király
Matti Lehtomäki
Xinlian Liang
author_facet Gábor Brolly
Géza Király
Matti Lehtomäki
Xinlian Liang
author_sort Gábor Brolly
collection DOAJ
description This paper presents a fully automatic method addressing tree mapping and parameter extraction (tree position, stem diameter at breast height, stem curve, and tree height) from terrestrial laser scans in forest inventories. The algorithm is designed to detect trees of various sizes and architectures, produce smooth yet accurate stem curves, and achieve tree height estimates in multi-layered stands, all without employing constraints on the shape of the crown. The algorithm also aims to balance estimation accuracy and computational complexity. The method’s tree detection combines voxel operations and stem surface filtering based on scanning point density. Stem diameters are obtained by creating individual taper models, while tree heights are estimated from the segmentation of tree crowns in the voxel-space. Twenty-four sample plots representing diverse forest structures in the south boreal region of Finland have been assessed from single- and multiple terrestrial laser scans. The mean percentages of completeness in stem detection over all stand complexity categories are 50.9% and 68.5% from single and multiple scans, respectively, while the mean root mean square error (RMSE) of the stem curve estimates ranges from ±1.7 to ±2.3 cm, all of which demonstrates the robustness of the algorithm. Efforts were made to accurately locate tree tops by segmenting individual crowns. Nevertheless, with a mean bias of −2.9 m from single scans and −1.3 m from multiple scans, the algorithm proved conservative in tree height estimates.
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spelling doaj.art-f67c87f3d4b14a6e9f8d0c21d5bf41e12023-12-03T12:15:12ZengMDPI AGRemote Sensing2072-42922021-02-0113454210.3390/rs13040542Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest InventoryGábor Brolly0Géza Király1Matti Lehtomäki2Xinlian Liang3Faculty of Forestry, Institute of Geomatics and Civil Engineering, University of Sopron, Bajcsy-Zsilinszky 4, H-9400 Sopron, HungaryFaculty of Forestry, Institute of Geomatics and Civil Engineering, University of Sopron, Bajcsy-Zsilinszky 4, H-9400 Sopron, HungaryDepartment of Remote Sensing and Photogrammetry, Finnish Geospatial Research Institute, National Land Survey of Finland, Geodeetinrinne 2, FI-02430 Masala, FinlandDepartment of Remote Sensing and Photogrammetry, Finnish Geospatial Research Institute, National Land Survey of Finland, Geodeetinrinne 2, FI-02430 Masala, FinlandThis paper presents a fully automatic method addressing tree mapping and parameter extraction (tree position, stem diameter at breast height, stem curve, and tree height) from terrestrial laser scans in forest inventories. The algorithm is designed to detect trees of various sizes and architectures, produce smooth yet accurate stem curves, and achieve tree height estimates in multi-layered stands, all without employing constraints on the shape of the crown. The algorithm also aims to balance estimation accuracy and computational complexity. The method’s tree detection combines voxel operations and stem surface filtering based on scanning point density. Stem diameters are obtained by creating individual taper models, while tree heights are estimated from the segmentation of tree crowns in the voxel-space. Twenty-four sample plots representing diverse forest structures in the south boreal region of Finland have been assessed from single- and multiple terrestrial laser scans. The mean percentages of completeness in stem detection over all stand complexity categories are 50.9% and 68.5% from single and multiple scans, respectively, while the mean root mean square error (RMSE) of the stem curve estimates ranges from ±1.7 to ±2.3 cm, all of which demonstrates the robustness of the algorithm. Efforts were made to accurately locate tree tops by segmenting individual crowns. Nevertheless, with a mean bias of −2.9 m from single scans and −1.3 m from multiple scans, the algorithm proved conservative in tree height estimates.https://www.mdpi.com/2072-4292/13/4/542remote sensingforest inventoryterrestrial laser scanningpoint cloud processingautomatic tree extractionstem curve
spellingShingle Gábor Brolly
Géza Király
Matti Lehtomäki
Xinlian Liang
Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest Inventory
Remote Sensing
remote sensing
forest inventory
terrestrial laser scanning
point cloud processing
automatic tree extraction
stem curve
title Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest Inventory
title_full Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest Inventory
title_fullStr Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest Inventory
title_full_unstemmed Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest Inventory
title_short Voxel-Based Automatic Tree Detection and Parameter Retrieval from Terrestrial Laser Scans for Plot-Wise Forest Inventory
title_sort voxel based automatic tree detection and parameter retrieval from terrestrial laser scans for plot wise forest inventory
topic remote sensing
forest inventory
terrestrial laser scanning
point cloud processing
automatic tree extraction
stem curve
url https://www.mdpi.com/2072-4292/13/4/542
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AT mattilehtomaki voxelbasedautomatictreedetectionandparameterretrievalfromterrestriallaserscansforplotwiseforestinventory
AT xinlianliang voxelbasedautomatictreedetectionandparameterretrievalfromterrestriallaserscansforplotwiseforestinventory