Centre dedocumentation
scientifique

Analyzing the role of pulse density and voxelization parameters on full-waveform LiDAR-derived metrics / Pablo Crespo-Peremarch in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)  

Public [article]  inISPRS Journal of photogrammetry and remote sensing > vol 146 (December 2018) . - pp 453 - 464 Titre : Analyzing the role of pulse density and voxelization parameters on full-waveform LiDAR-derived metrics Type de document : Article/Communication Auteurs : Pablo Crespo-Peremarch, Auteur ; Luis Ángel Ruiz, Auteur ; Angel Balaguer-Beser, Auteur ; Javier Estornell, Auteur Année de publication : 2018 Article en page(s) : pp 453 - 464 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie [Termes descripteurs IGN] Abies grandis [Termes descripteurs IGN] Acer macrophyllum [Termes descripteurs IGN] amplitude [Termes descripteurs IGN] données lidar [Termes descripteurs IGN] données localisées 3D [Termes descripteurs IGN] étalonnage en vol [Termes descripteurs IGN] filtrage du bruit [Termes descripteurs IGN] forme d'onde pleine [Termes descripteurs IGN] impulsion laser [Termes descripteurs IGN] lidar à retour d'onde complète [Termes descripteurs IGN] Oregon (Etats-Unis) [Termes descripteurs IGN] prétraitement du signal [Termes descripteurs IGN] pseudotsuga menziesii [Termes descripteurs IGN] Thuja plicata [Termes descripteurs IGN] tsuga heterophylla [Termes descripteurs IGN] voxel Résumé : (auteur) LiDAR full-waveform (LFW) pulse density is not homogeneous along study areas due to overlap between contiguous flight stripes and, to a lesser extent, variations in height, velocity and altitude of the platform. As a result, LFW-derived metrics extracted at the same spot but at different pulse densities differ, which is called “side-lap effect”. Moreover, this effect is reflected in forest stand estimates, since they are predicted from LFW-derived metrics. This study was undertaken to analyze LFW-derived metric variations according to pulse density, voxel size and value assignation method in order to reduce the side-lap effect. Thirty LiDAR samples with a minimum density of 16 pulses.m−2 were selected from the testing area and randomly reduced to 2 pulses.m−2 with an interval of 1 pulse.m−2, then metrics were extracted and compared for each sample and pulse density at different voxel sizes and assignation values. Results show that LFW-derived metric variations as a function of pulse density follow a negative exponential model similar to the exponential semivariogram curve, increasing sharply until they reach a certain pulse density, where they become stable. This value represents the minimum pulse density (MPD) in the study area to optimally minimize the side-lap effect. This effect can also be reduced with pulse densities lower than the MPD modifying LFW parameters (i.e. voxel size and assignation value). Results show that LFW-derived metrics are not equally influenced by pulse density, such as number of peaks (NP) and ROUGHness of the outermost canopy (ROUGH) that may be discarded for further analyses at large voxel sizes, given that they are highly influenced by pulse density. In addition, side-lap effect can be reduced by either increasing pulse density or voxel size, or modifying the assignation value. In practice, this leads to a proper estimate of forest stand variables using LFW data. Numéro de notice : A2018-543 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.10.012 date de publication en ligne : 05/11/2018 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.10.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91569 [article]

Réservation

Réserver ce document

Exemplaires (3)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
081-2018131	RAB	Revue	Centre de documentation	En réserve 3L	Disponible
081-2018133	DEP-EXM	Revue	MATIS	Dépôt en unité	Exclu du prêt
081-2018132	DEP-EAF	Revue	Nancy	Dépôt en unité	Exclu du prêt

Accuracy of tree geometric parameters depending on the LiDAR data density / Edyta Hadas in European journal of remote sensing, vol 49 (2016)  

Public [article]  inEuropean journal of remote sensing > vol 49 (2016) . - pp 73 - 92 Titre : Accuracy of tree geometric parameters depending on the LiDAR data density Type de document : Article/Communication Auteurs : Edyta Hadas, Auteur ; Javier Estornell, Auteur Année de publication : 2016 Article en page(s) : pp 73 - 92 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie [Termes descripteurs IGN] données lidar [Termes descripteurs IGN] données localisées 3D [Termes descripteurs IGN] hauteur des arbres [Termes descripteurs IGN] houppier [Termes descripteurs IGN] Olea europaea [Termes descripteurs IGN] précision géométrique (imagerie) Résumé : (auteur) The aim of this study was to compare geometric parameters of olive trees (tree height,crown base height, crown diameters, crown area), using LiDAR data of different densities: 0.5, 3.5 and 9 points m-2. Two strategies were proposed and verified with a focus on raster and raw data analysis. Statistical tests have shown, that for the tree height and crown base height estimation, the choice of strategy was irrelevant, but denser LiDAR data provided more accurate results. The raster analysis strategy applied for sparse and dense LiDAR datasets allowed crown shape to be determined with a similar accuracy which means raster data are useful for estimating other indirect tree parameters. The quality of results was independent from the tree size. Numéro de notice : A2016-833 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article En ligne : http://dx.doi.org/10.5721/EuJRS20164905 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82718 [article]