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M. Maimaitijiang, V. Sagan, H. Erkbol, J. Adrian, M. Newcomb, D. LeBauer, D. Pauli, N. Shakoor, T. C. Mockler
2020 ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
A series of canopy structure metrics were extracted using LiDAR and RGB photogrammetry-based point clouds.  ...  In addition, Pearson's correlation coefficient, as well as RFR-based variable importance analysis demonstrated that height-based metrics from both LiDAR and photogrammetric point clouds were more useful  ...  ACKNOWLEDGEMENTS This work was supported by the Department of Energy (ARPA-E awards #DE-AR0000594).  ... 
doi:10.5194/isprs-annals-v-3-2020-489-2020 fatcat:2izgfs7ttvfrdnzrisupjjtd4y

Individual Tree Parameters Estimation for Chinese Fir (Cunninghamia lanceolate (Lamb.) Hook) Plantations of South China Using UAV Oblique Photography: Possibilities and Challenges

Tian Yin, Jian Zeng, Xiaoli Zhang, Xuemei Zhou
2020 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
For the crown delineation, it is more accurate based on the 0.25 m resolution using MCWS algorithm with the detection accuracy of 65%.  ...  This article proposes a framework for extracting individual tree parameters by combining low-cost and high-efficiency unmanned aerial vehicle-based oblique photogrammetry with manned airborne light detection  ...  Lei Zhao from the Institute of Forest Resource Information Techniques CAF for their help with the field work.  ... 
doi:10.1109/jstars.2020.3038819 fatcat:ejofrscsknbwnnqnxwc22qqeny


D. Skarlatos, M. Vlachos
2018 ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
Two areas were tested, based on the availability of ground reference points, both under trees and among vegetation, as well as on terrain.  ...  of the derived DTMs in contrast with the DSMs.  ...  They would also thank Electricity Authority of Cyprus from providing authorising data acquisition on Vasiliko site, and students K. Symeou and A. Panagiotou for their help in data acquisition.  ... 
doi:10.5194/isprs-annals-iv-2-255-2018 fatcat:oxaasoykinfcnfessnwbxfjybe

DEM Generation from Fixed-Wing UAV Imaging and LiDAR-Derived Ground Control Points for Flood Estimations

Jairo R. Escobar Villanueva, Luis Iglesias Martínez, Jhonny I. Pérez Montiel
2019 Sensors  
Also, the flood estimates (volume and area) of the UAV terrain products are compared with a LiDAR-based reference.  ...  Lastly, it proves the complementarity between LiDAR and UAV photogrammetry at the local level.  ...  While discrepancies are evident between UAV models and the reference LiDAR, they are due to the DEM generation strategy, which is highly sensitive to the filtering method for ground point extraction and  ... 
doi:10.3390/s19143205 fatcat:wubx3q75xngmxh6uz3birjqjdm

Individual Tree Detection and Qualitative Inventory of a Eucalyptus sp. Stand Using UAV Photogrammetry Data

André Almeida, Fabio Gonçalves, Gilson Silva, Adriano Mendonça, Maria Gonzaga, Jeferson Silva, Rodolfo Souza, Igor Leite, Karina Neves, Marcus Boeno, Braulio Sousa
2021 Remote Sensing  
The normalized 3D point cloud enabled the identification of over 95% of the stand trees and the estimation of their heights with an RMSE of 0.36 m (11%).  ...  In addition, we assessed the quality of a DAP-UAV digital terrain model (DTM) derived using an alternative ground classification approach and investigated its performance in the retrieval of individual  ...  To create the dense cloud point (around 2200 points m −2 ), the parameters were set as "high" for quality and "mild" for depth filtering mode.  ... 
doi:10.3390/rs13183655 fatcat:7f44oqmscrdezj2x5b7kn72olm

Comparing Filtering Techniques for Removing Vegetation from UAV-Based Photogrammetric Point Clouds

Niels Anders, João Valente, Rens Masselink, Saskia Keesstra
2019 Drones  
The objective in this study was, therefore, to assess the performance of various vegetation filter algorithms for SfM-obtained point clouds.  ...  For areas with shrubs and trees, the ISL_VI and TIN method performed best. These results show that different filtering techniques have various degrees of success in different use cases.  ...  Acknowledgments: We would like to thank Erik Cammeraat for the organization and assistance of the field work, and two anonymous reviewers for improving this paper.  ... 
doi:10.3390/drones3030061 fatcat:vwuxn6srlrcencrncqc7kpvxga

Tree Height Estimation of Forest Plantation in Mountainous Terrain from Bare-Earth Points Using a DoG-Coupled Radial Basis Function Neural Network

Haiqing He, Yeli Yan, Ting Chen, Penggen Cheng
2019 Remote Sensing  
Bare-earth Index (BEI) and Shadow Index (SI) were used to separate ground points from the image-derived point clouds.  ...  With the UAV-based image acquisition and image-derived point clouds, we constructed a 5 cm-resolution Digital Surface Model (DSM), which was assessed against 14 independent checkpoints measured by a Real-Time  ...  Conflicts of Interest: The authors declare no conflict of interest. Remote Sens. 2019, 11, 1271  ... 
doi:10.3390/rs11111271 fatcat:o5vks54bxbgzzohynytubetopu

Evaluation of UAV LiDAR for Mapping Coastal Environments

Yi-Chun Lin, Yi-Ting Cheng, Tian Zhou, Radhika Ravi, Seyyed Meghdad Hasheminasab, John Evan Flatt, Cary Troy, Ayman Habib
2019 Remote Sensing  
The quality of LiDAR, as well as image-based point clouds, are investigated and compared over different geomorphic environments in terms of their point density, relative and absolute accuracy, and area  ...  UAV LiDAR has a clear advantage in terms of large and uniform ground coverage over different geomorphic environments, higher point density, and ability to penetrate through vegetation to capture points  ...  We are also grateful for the support of the Dune Acres and Beverly Shores communities, who facilitated access to the beaches. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs11242893 fatcat:57vk7nzvb5eu5nv27xeizz745e

Comparison of UAV LiDAR and Digital Aerial Photogrammetry Point Clouds for Estimating Forest Structural Attributes in Subtropical Planted Forests

Lin Cao, Hao Liu, Xiaoyao Fu, Zhengnan Zhang, Xin Shen, Honghua Ruan
2019 Forests  
In this study, we compared two suites of point cloud metrics and the accuracies of predictive models of forest structural attributes using unmanned aerial vehicle (UAV) light detection and ranging (LiDAR  ...  A comparison between UAV-LiDAR and UAV-DAP metrics was performed across plots among different tree species, heights, and stem densities.  ...  Acknowledgments: The authors gratefully acknowledge the foresters in Dongtai forest for their assistance with data collection, and for sharing their rich knowledge and working experience of the local forest  ... 
doi:10.3390/f10020145 fatcat:4rubybpu2rfkrdspleppt2k554


K. Bakuła, W. Ostrowski, M. Szender, W. Plutecki, A. Salach, K. Górski
2016 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
The final products of the proposed UAV data processing are digital elevation models, an orthophotomap and colour point clouds.  ...  The Iterative Closest Point (ICP) algorithm, as well as measurements of control points, were used to georeference the LiDAR data.  ...  ACKNOWLEDGEMENTS This study was performed with the cooperation of the Warsaw University of Technology, the Faculty of Geodesy and Cartography with the company MSP, within the frames of delivery and commissioning  ... 
doi:10.5194/isprs-archives-xli-b1-773-2016 fatcat:5ilbdu4dj5hy5clypdnwvcbs5q

Growth Height Determination of Tree Walls for Precise Monitoring in Apple Fruit Production Using UAV Photogrammetry

Marius Hobart, Michael Pflanz, Cornelia Weltzien, Michael Schirrmann
2020 Remote Sensing  
The resulting height models were compared with ground-based light detection and ranging (LiDAR) data as reference.  ...  It was shown that the tree wall profiles from the UAV point clouds were strongly correlated with the LiDAR point clouds of two years (2018: R² = 0.83; 2019: R² = 0.88).  ...  We would also like to thank Antje Giebel, who always came to our assistance when there were problems with the 3D point cloud calculation, and Michael Heisig, who helped with LiDAR point cloud calculation  ... 
doi:10.3390/rs12101656 fatcat:yigse2sojvbxfa3b5kfgyayosm

Structure from Motion Photogrammetry in Forestry: a Review

Jakob Iglhaut, Carlos Cabo, Stefano Puliti, Livia Piermattei, James O'Connor, Jacqueline Rosette
2019 Current Forestry Reports  
The camera poses and parameters obtained from SfM are then applied to generate a densified point cloud using MVS algorithms.  ...  SIFT), (2) SfM with camera parameters and a sparse point cloud as output and (3) the densified point cloud following MVS Fig. 3 3 Image quality issues illustrated by simulated degradations on UAV image  ... 
doi:10.1007/s40725-019-00094-3 fatcat:betgfmarszavxgak2ykpb43nei

Evaluating the Performance of Photogrammetric Products Using Fixed-Wing UAV Imagery over a Mixed Conifer–Broadleaf Forest: Comparison with Airborne Laser Scanning

Sadeepa Jayathunga, Toshiaki Owari, Satoshi Tsuyuki
2018 Remote Sensing  
Moreover, many previous studies attempted to compare photogrammetric products i.e., point clouds, CHMs and structural metrics with LiDAR data [19, [39] [40] [41] [42] [43] [44] [45] [46] [47] [48] [49]  ...  Following the principles of traditional stereoscopic photogrammetry, SfM uses multiple images from different angular viewpoints to identify well-defined geometric features and to generate a 3D point cloud  ...  Satoshi Tsuyuki advised on the RS data analysis, interpretation of the results and contributed in manuscript writing and revision. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs10020187 fatcat:tljvxucdwvg4db7boqkiycfl7u

Application of UAV Photogrammetric System for Monitoring Ancient Tree Communities in Beijing

Zixuan Qiu, Zhong-Ke Feng, Mingming Wang, Zhenru Li, Chao Lu
2018 Forests  
, the proposed method can realize the measurement of tree height, crown width, and prediction of DBH and tree age with low cost, high efficiency, and high precision.  ...  Through experiments and analysis, the root mean square error (RMSE) of the tree height measurement was 0.1814 m, the RMSE of the crown width measurement was 0.3292 m, the RMSE of the DBH prediction was  ...  Image construction point cloud minus LiDAR DEM obtains a terrain-normalized point cloud and performs hierarchical analysis according to the slope Discussion Comparative Analysis of UAV Photogrammetry  ... 
doi:10.3390/f9120735 fatcat:oup4lwmwsrc6zhj5w5alxvhyzi

Mapping Canopy Heights in Dense Tropical Forests Using Low-Cost UAV-Derived Photogrammetric Point Clouds and Machine Learning Approaches

He Zhang, Marijn Bauters, Pascal Boeckx, Kristof Van Oost
2021 Remote Sensing  
of local minima filters, supervised machine learning algorithms and TIN densification for classifying ground points using spectral and geometrical features from the UAV-based 3D data.  ...  Data derived from digital aerial photogrammetry (DAP) on the unmanned aerial vehicle (UAV) platform offer several advantages over field- and LiDAR-based approaches in terms of scale and efficiency, and  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs13183777 fatcat:xguor7m3irhlrearmjlhy7sibm
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