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Assessment of the influence of flying altitude and scan angle on biophysical vegetation products derived from airborne laser scanning / F. Morsdorf in International Journal of Remote Sensing IJRS, vol 29 n° 5 (March 2008)
[article]
Titre : Assessment of the influence of flying altitude and scan angle on biophysical vegetation products derived from airborne laser scanning Type de document : Article/Communication Auteurs : F. Morsdorf, Auteur ; O. Frey, Auteur ; E. Meier, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 1387 - 1406 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] altitude du capteur
[Termes IGN] angle d'incidence
[Termes IGN] angle de visée
[Termes IGN] couvert végétal
[Termes IGN] données laser
[Termes IGN] hauteur des arbres
[Termes IGN] instrumentation Toposys
[Termes IGN] Leaf Area Index
[Termes IGN] modèle numérique de terrain
[Termes IGN] parc naturel
[Termes IGN] plan de vol
[Termes IGN] signal laser
[Termes IGN] Suisse
[Termes IGN] télémétrie laser aéroportéRésumé : (Auteur) Airborne Laser Scanning (ALS) has been established as a valuable tool for the estimation of biophysical vegetation properties such as tree height, crown width, fractional cover and leaf area index (LAI). It is expected that the conditions of data acquisition, such as viewing geometry and sensor configuration influence the value of these parameters. In order to gain knowledge about these different conditions, we test for the sensitivity of vegetation products for viewing geometry, namely flying altitude and scanning (incidence) angle. Based on two methodologies for single tree extraction and derivation of fractional cover and LAI previously developed and published by our group, we evaluate how these variables change with either flying altitude or scanning angle. These are the two parameters which often need to be optimized towards the best compromise between point density and area covered with a single flight line, in order to reduce acquisition costs. Our test-site in the Swiss National Park was sampled with two nominal flying altitudes, 500 and 900 m above ground. Incidence angle and local incidence angle were computed based on the digital terrain model using a simple backward geocoding procedure. We divided the raw laser returns into several different incident angle classes based on the flight path data; the TopoSys Falcon II system used in this study has a maximum scan angle of + 7.15°. We compared the derived biophysical properties from each of these classes with field measurements based on tachymeter measurements and hemispherical photographs, which were geolocated using differential GPS. It was found that with increasing flying height the well-known underestimation of tree height increases. A similar behaviour can be observed for fractional cover; its respective values decrease with higher flying height. The minimum distance between first and last echo increases from 1.2 metres for 500 m AGL to more than 3 metres for 900 m AGL, which does alter return statistics. The behaviour for incidence angles is not so evident, probably due to the small scanning angle of the system used. fCover seems to be most affected by incidence angles, with significantly higher differences for locations further away from nadir. As expected, incidence angle appears to be of higher importance for vegetation density parameters than local incidence angle. Numéro de notice : A2008-081 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160701736349 En ligne : https://doi.org/10.1080/01431160701736349 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29076
in International Journal of Remote Sensing IJRS > vol 29 n° 5 (March 2008) . - pp 1387 - 1406[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-08031 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Automatic forest inventory parameter determination from terrestrial laser scanner data / Hans-Gerd Maas in International Journal of Remote Sensing IJRS, vol 29 n° 5 (March 2008)
[article]
Titre : Automatic forest inventory parameter determination from terrestrial laser scanner data Type de document : Article/Communication Auteurs : Hans-Gerd Maas, Auteur ; A. Bienert, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 1579 - 1593 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données laser
[Termes IGN] données localisées 3D
[Termes IGN] hauteur des arbres
[Termes IGN] image terrestre
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] lasergrammétrie
[Termes IGN] semis de points
[Termes IGN] sylviculture
[Termes IGN] télémétrie laser terrestreRésumé : (Auteur) Terrestrial laser scanners find rapidly growing interest in photogrammetry as efficient tools for fast and reliable three-dimensional (3D) point cloud data acquisition. They have opened a wide range of application fields within a short period of time. Beyond interactive measurement in 3D point clouds, techniques for the automatic detection of objects and the determination of geometric parameters form a high priority research issue. With the quality of 3D point clouds generated by laser scanners and the automation potential in data processing, terrestrial laser scanning is also becoming a useful tool for forest inventory. This paper presents a brief review of current laser scanner systems from a technological point of view and discusses different scanner technologies and system parameters regarding their suitability for forestry applications. Methods for the automatic detection of trees in terrestrial laser scanner data as well as the automatic determination of diameter at breast height (DBH), tree height and 3D stem profiles are outlined. Reliability and precision of the techniques are analysed on the basis of several pilot studies. In these pilot studies more than 97% of the trees could be detected correctly, and DBH could be determined with a precision of about 1.8 cm. Copyright Taylor & Francis Numéro de notice : A2008-084 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160701736406 En ligne : https://doi.org/10.1080/01431160701736406 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29079
in International Journal of Remote Sensing IJRS > vol 29 n° 5 (March 2008) . - pp 1579 - 1593[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-08031 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Mapping the height and above-ground biomass of a mixed forest using lidar and stereo Ikonos images / Benoît Saint-Onge in International Journal of Remote Sensing IJRS, vol 29 n° 5 (March 2008)
[article]
Titre : Mapping the height and above-ground biomass of a mixed forest using lidar and stereo Ikonos images Type de document : Article/Communication Auteurs : Benoît Saint-Onge, Auteur ; Y. Hu, Auteur ; Cédric Vega , Auteur Année de publication : 2008 Article en page(s) : pp 1277 - 1294 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] canopée
[Termes IGN] données lidar
[Termes IGN] forêt
[Termes IGN] hauteur des arbres
[Termes IGN] image à résolution métrique
[Termes IGN] image Ikonos
[Termes IGN] masse végétale
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique de terrain
[Termes IGN] modèle stéréoscopiqueRésumé : (Auteur) Our objective was to assess the accuracy of the forest height and biomass estimates derived from an Ikonos stereo pair and a lidar digital terrain model (DTM). After the Ikonos scenes were registered to the DTM with submetric accuracy, tree heights were measured individually by subtracting the photogrammetric elevation of the treetop from the lidar ground-level elevation of the tree base. The low residual error (1.66 m) of the measurements confirmed the joint geometric accuracy of the combined models. Matched images of the stereo pair were then used to create a digital surface model. The latter was transformed to a canopy height model (CHM) by subtracting the lidar DTM. Plotwise height percentiles were extracted from the Ikonos-lidar CHM and used to predict the average dominant height and above-ground biomass. The coefficient of determination reached 0.91 and 0.79 for average height and biomass, respectively. In both cases, the accuracy of the Ikonos-lidar CHM predictions was slightly lower than that of the all-lidar reference CHM. Although the CHM heights did not saturate at moderate biomass levels, as do multispectral or radar images, values above 300 Mg ha-1 could not be predicted accurately by the Ikonos-lidar or by the all-lidar CHM. Copyright Taylor & Francis Numéro de notice : A2008-080 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160701736505 En ligne : https://doi.org/10.1080/01431160701736505 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29075
in International Journal of Remote Sensing IJRS > vol 29 n° 5 (March 2008) . - pp 1277 - 1294[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-08031 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Species identification of individual trees by combining high resolution LiDAR data with multi-spectral images / Johan Holmgren in International Journal of Remote Sensing IJRS, vol 29 n° 5 (March 2008)
[article]
Titre : Species identification of individual trees by combining high resolution LiDAR data with multi-spectral images Type de document : Article/Communication Auteurs : Johan Holmgren, Auteur ; A. Persson, Auteur ; U. Sodermans, Auteur Année de publication : 2008 Article en page(s) : pp 1537 - 1552 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse discriminante
[Termes IGN] données lidar
[Termes IGN] flore locale
[Termes IGN] houppier
[Termes IGN] identification automatique
[Termes IGN] image multibande
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestris
[Termes IGN] Suède
[Termes IGN] sylviculture
[Termes IGN] traitement du signalRésumé : (Auteur) The objectives of this study were to identify useful predictive factors for tree species identification of individual trees and to compare classifications based on a combination of LiDAR data and multi-spectral images with classification by the use of each individual data source. Crown segments derived from LiDAR data were mapped to multi-spectral images for extraction of spectral data within individual tree crowns. Several features, related to height distribution of laser returns in the canopy, canopy shape, proportion of different types of laser returns, and intensity of laser returns, were derived from LiDAR data. Data from a test site in southern Sweden were used (lat. 58°30' N, long. 13°40' E). The forest consisted of Norway spruce (Picea abies), Scots pine (Pinus sylvestris), and deciduous trees. Classification into these three tree species groups was validated for 1711 trees that had been detected in LiDAR data within 14 field plots (sizes of 20x50 m or 80x80 m). The LiDAR data were acquired by the TopEye MkII system (50 LiDAR measurements per m) and the multi-spectral images were taken by the Zeiss/Intergraph Digital Mapping Camera. The overall classification accuracy was 96% when both data sources were combined. Copyright Taylor & Francis Numéro de notice : A2008-083 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160701736471 En ligne : https://doi.org/10.1080/01431160701736471 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29078
in International Journal of Remote Sensing IJRS > vol 29 n° 5 (March 2008) . - pp 1537 - 1552[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-08031 RAB Revue Centre de documentation En réserve L003 Exclu du prêt 3D modelling of castles / Sabry F. El Hakim in GIM international, vol 22 n° 3 (March 2008)
[article]
Titre : 3D modelling of castles Type de document : Article/Communication Auteurs : Sabry F. El Hakim, Auteur ; Fabio Remondino, Auteur ; F. Voltolini, Auteur Année de publication : 2008 Article en page(s) : pp 21 - 25 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] caméra numérique
[Termes IGN] château
[Termes IGN] données laser
[Termes IGN] lasergrammétrie
[Termes IGN] reconstruction 3D du bâti
[Termes IGN] restauration de bâtiment
[Termes IGN] texture d'imageRésumé : (Auteur) Three-dimensional documentation of heritage buildings is important for conservation, restoration and education. When it comes to complex architectural structures such as castles, no single modelling technique is capable of yielding cost-effective, highly detailed and accurate photo-realism. The authors demonstrate how integration of multiple techniques brings resolution. Copyright Reed Business Information Numéro de notice : A2008-053 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29048
in GIM international > vol 22 n° 3 (March 2008) . - pp 21 - 25[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 061-08031 RAB Revue Centre de documentation En réserve L003 Disponible Création, administration et utilisation d'un modèle urbain numérique en 3D / G. Forkert in XYZ, n° 114 (mars - mai 2008)PermalinkImproving National Land Cover Database estimates of road network impervious cover using vector road networks in GIS / K. Thomas in SaLIS Surveying and land information science, vol 68 n° 1 (March 2008)PermalinkPanorama des potentialités SIG en 3 dimensions : vers des modèles virtuels 3D de villes / Robert Laurini in XYZ, n° 114 (mars - mai 2008)PermalinkParametric investigation of the performance of Lidar filters using different surface contexts / S. Seo in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 3 (March 2008)PermalinkPhotogrammetric and LIDAR data integration using the centroid of a rectangular roof as a control point / Edson Aparecido Mitishita in Photogrammetric record, vol 23 n° 121 (March - May 2008)PermalinkReconstitution de la géométrie d'un glacier disparu et modélisation des conséquences de sa disparition : exemple du glacier durancien lors du dernier maximum glaciaire / E. Cossart in Revue internationale de géomatique, vol 18 n° 1 (mars – mai 2008)PermalinkSIG et 3D au service des collectivités territoriales : l'expérience de la ville du Havre / Olivier Banaszak in XYZ, n° 114 (mars - mai 2008)PermalinkVers la création d'un méta-modèle générique de l'information spatiale 3D urbaine / Roland Billen in XYZ, n° 114 (mars - mai 2008)Permalink3D : l'incontournable révolution / Françoise de Blomac in SIG la lettre, n° 94 (février 2008)PermalinkExtracting urban road networks from high-resolution true orthoimage and Lidar / J. Youn in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 2 (February 2008)PermalinkRaster modelling of coastal flooding from sea-level rise / B. Poulter in International journal of geographical information science IJGIS, vol 22 n° 1-2 (february 2008)PermalinkWinBasin: using improved algorithms and the GIS technique for automated watershed modelling analysis from digital elevation models / W. Lin in International journal of geographical information science IJGIS, vol 22 n° 1-2 (february 2008)PermalinkPermalinkAdvances in photogrammetry, remote sensing and spatial information sciences / Z. Li (2008)PermalinkAnalyse spatiale des activités socio-économiques dans Londres et sa banlieue / Guillaume Olive (2008)PermalinkAnalyse et traitement d'ondes Lidar pour la cartographie et la reconnaissance de formes : application au milieu urbain / Clément Mallet (2008)PermalinkPermalinkPermalinkAutomatic pyramidal intensity-based laser scan matcher for 3D modeling of large scale unstructured environments / Daniela Craciun (2008)PermalinkPermalink