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A model-based approach for reconstructing a terrain surface from airborne Lidar data / Gunho Sohn in Photogrammetric record, vol 23 n° 122 (June - August 2008)
[article]
Titre : A model-based approach for reconstructing a terrain surface from airborne Lidar data Type de document : Article/Communication Auteurs : Gunho Sohn, Auteur ; Ian J. Dowman, Auteur Année de publication : 2008 Article en page(s) : pp 170 - 193 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] filtrage de points
[Termes IGN] modèle numérique de surface
[Termes IGN] optimisation (mathématiques)
[Termes IGN] pente
[Termes IGN] semis de pointsRésumé : (Auteur) A lidar filtering technique is used to differentiate on-terrain points and off-terrain points from a cloud of 3D point data collected by a lidar system. A major issue of concern in this low-level filter is to design a methodology to ensure a continual adaptation to variations of terrain slopes and object scales. In this paper, a new lidar filtering technique which hierarchically fragments lidar data into piecewise planar terrain models is introduced. Once a number of hypothetical planar terrain models are generated to fit the terrain surface of the underlying area, the optimal terrain model to produce the minimum labelling errors is determined based on minimum description length (MDL) principles. This hypothesis-verification optimisation is achieved in a coarse-to-fine strategy by which the entire terrain surface is incrementally reconstructed by increasing the number of planar terrain models fitted. The proposed technique was successfully applied to a digital surface model provided within an OEEPE lidar trial, showing 0·94% of Type I errors and 6·75% of Type II errors compared to manually classified reference data. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2008-296 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2008.00483.x En ligne : https://doi.org/10.1111/j.1477-9730.2008.00483.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29289
in Photogrammetric record > vol 23 n° 122 (June - August 2008) . - pp 170 - 193[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-08021 RAB Revue Centre de documentation En réserve L003 Disponible Image-based 3D surface reconstruction by combination of photometric, geometric, and real-aperture methods / Pablo d' Angelo in ISPRS Journal of photogrammetry and remote sensing, vol 63 n° 3 (May - June 2008)
[article]
Titre : Image-based 3D surface reconstruction by combination of photometric, geometric, and real-aperture methods Type de document : Article/Communication Auteurs : Pablo d' Angelo, Auteur ; C. Wöhler, Auteur Année de publication : 2008 Article en page(s) : pp 297 - 321 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] données de terrain
[Termes IGN] gradient de pente
[Termes IGN] pente
[Termes IGN] photométrie
[Termes IGN] polarisation
[Termes IGN] profondeur
[Termes IGN] programmation non linéaire
[Termes IGN] reconstruction 3D
[Termes IGN] réflectanceRésumé : (Auteur) An image-based 3D surface reconstruction method based on simultaneous evaluation of intensity and polarisation features (shape from photopolarimetric reflectance) and its combination with absolute depth data is introduced in this article. The proposed technique is based on the analysis of single or multiple intensity and polarisation images. To compute the surface gradients, we present a global optimisation method based on a variational framework and a local optimisation method based on solving a set of non-linear equations individually for each image pixel. These approaches are suitable for strongly non-Lambertian surfaces and those of diffuse reflectance behaviour and can also be adapted to surfaces of non-uniform albedo. We describe how independently measured absolute depth data is integrated into the shape from photopolarimetric reflectance framework in order to increase the accuracy of the 3D reconstruction result. In this context we concentrate on dense but noisy depth data obtained by depth from defocus and on sparse but accurate depth data obtained by stereo or structure from motion analysis. We show that depth from defocus information should preferentially be used for initialising the optimisation schemes for the surface gradients. For integration of sparse depth information, we suggest an optimisation scheme that simultaneously adapts the surface gradients to the measured intensity and polarisation data and to the surface slopes implied by depth differences between pairs of depth points. In principle, arbitrary sources of depth information are possible in the presented framework. Experiments on synthetic and on real-world data reveal that while depth from defocus is especially helpful for providing an initial estimate of the surface gradients and the albedo in the absence of a-priori knowledge, integration of stereo or structure from motion information significantly increases the 3D reconstruction accuracy. In our real-world experiments, we regard the scenarios of 3D reconstruction of raw forged iron surfaces in the domain of industrial quality inspection and the generation of a digital elevation model of a section of the lunar surface in the context of space-based planetary exploration. Copyright ISPRS Numéro de notice : A2008-213 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2007.09.005 En ligne : https://doi.org/10.1016/j.isprsjprs.2007.09.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29208
in ISPRS Journal of photogrammetry and remote sensing > vol 63 n° 3 (May - June 2008) . - pp 297 - 321[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-08031 SL Revue Centre de documentation Revues en salle Disponible
Titre : Lidar data classification using hierarchical K-means clustering Type de document : Article/Communication Auteurs : Frédéric Bretar, Auteur ; Nicolas David , Auteur ; Nesrine Chehata , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2008 Collection : International Archives of Photogrammetry and Remote Sensing, ISSN 0252-8231 num. 37-B3 Conférence : ISPRS 2008, 21st ISPRS world congress 03/07/2008 11/07/2008 Pékin Chine OA ISPRS Archives Importance : pp 325 - 330 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse de groupement
[Termes IGN] classification ascendante hiérarchique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] filtrage de points
[Termes IGN] modèle numérique de terrain
[Termes IGN] pente
[Termes IGN] semis de pointsRésumé : (Auteur) This paper deals with lidar point cloud filtering and classification for modelling the Terrain and more generally for scene segmentation. In this study, we propose to use the well-known K-means clustering algorithm that filters and segments (point cloud) data. The K-means clustering is well adapted to lidar data processing, since different feature attributes can be used depending on the desired classes. Attributes may be geometric or textural when processing only 3D-point cloud but also spectral in case of joint use of optical images and lidar data. The algorithm is based on a fixed neighbourhood size that can deal with steep relief covered by dense vegetation, mountainous area and terrains which present micro-relieves. The novelty of our algorithm consists in providing a hierarchical splitting clustering to extract ground points. The number of cluster splits is used to qualify automatically the classification reliability. This point is rarely treated in previous works. Moreover landscape predictors such as slope map are used to locally refine the classification. Finally, the methodology is extended to a multi-scale framework. The hierarchical clustering is processed from coarse DTM resolution to finer one. This implementation improves the algorithm robustness and ensures reliable ground estimation. Quantitative and qualitative results are presented on the ISPRS data set. Numéro de notice : 10664 Affiliation des auteurs : MATIS (1993-2011) Thématique : IMAGERIE Nature : Communication DOI : sans En ligne : https://www.isprs.org/proceedings/XXXVII/congress/3b_pdf/65.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64215 Documents numériques
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10664_isprs_2008_chehata.pdfAdobe Acrobat PDF Spatial resolution and algorithm choice as modifiers of downslope flow computed from digital elevation models / K. Clarke in Cartography and Geographic Information Science, vol 34 n° 3 (July 2007)
[article]
Titre : Spatial resolution and algorithm choice as modifiers of downslope flow computed from digital elevation models Type de document : Article/Communication Auteurs : K. Clarke, Auteur ; S.J. Lee, Auteur Année de publication : 2007 Article en page(s) : pp 215 - 230 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] écoulement des eaux
[Termes IGN] limite de résolution géométrique
[Termes IGN] Matlab
[Termes IGN] modèle numérique de terrain
[Termes IGN] pente
[Termes IGN] représentation du reliefRésumé : (Auteur) This research investigated the dependence of computing downslope flow from digital elevation models (DEMs) on two basic elements of the flow calculation: the spatial resolution of the DEM and the algorithm used to compute the downslope flow, specifically how it defines topographic slope and aspect. Six algorithms for downslope flow and downslope accumulation were implemented in MATLAB using different assumptions about components of the computation from the terrain analysis literature. We analyzed the results of downslope flow statistically, thresholded the values to yield streams, and compared the different results with the actual surface streams in the National Hydrographic Database. We repeated the computations using DEMs of 3-m, 30-m, and 90-m resolutions, covering a test area near Santa Barbara, California. We conclude that downslope flow computations are overestimates, and that they are fraught with critical algorithmic assumptions and scale effects. They should be approached with great caution in GIS-based analyses. Copyright CaGISociety Numéro de notice : A2007-394 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1559/152304007781697875 En ligne : https://doi.org/10.1559/152304007781697875 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28757
in Cartography and Geographic Information Science > vol 34 n° 3 (July 2007) . - pp 215 - 230[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-07031 RAB Revue Centre de documentation En réserve L003 Disponible An experiment using a circular neighborhood to calculate slope gradient from a DEM / X. Shi in Photogrammetric Engineering & Remote Sensing, PERS, vol 73 n° 2 (February 2007)
[article]
Titre : An experiment using a circular neighborhood to calculate slope gradient from a DEM Type de document : Article/Communication Auteurs : X. Shi, Auteur ; A - Xing Zhu, Auteur ; et al., Auteur Année de publication : 2007 Article en page(s) : pp 143 - 154 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] données matricielles
[Termes IGN] gradient de pente
[Termes IGN] modèle numérique de surface
[Termes IGN] pente
[Termes IGN] relation topologique
[Termes IGN] relief
[Termes IGN] voisinage (relation topologique)Résumé : (Auteur) The traditional 3 X 3 cell neighbourhood used in a focal operation on a raster layer has a square shape that results in a dimensional neighbourhood of which the orientation is eventually arbitrary to the physical features represented. This paper presents an experiment using a circular neighbourhood to calculate slope gradient. Comparisons of the results from a circular neighbourhood with the results from some traditional methods show that (a) for a smooth surface, the result from a circular neighbourhood is more accurate than that from a square neighbourhood, (b) a circular neighbourhood is generally more sensitive to noise in the input DEM than a square neighbourhood, and (c) in a validation using field measurements, the circular neighbourhood performs better than the square neighbourhood when the ratio of user-specified neighbourhood size to cell size is high. Copyright ASPRS Numéro de notice : A2007-060 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.73.2.143 En ligne : https://doi.org/10.14358/PERS.73.2.143 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28425
in Photogrammetric Engineering & Remote Sensing, PERS > vol 73 n° 2 (February 2007) . - pp 143 - 154[article]Übergangsbogen für Bahnen mit hohen Fahrgeschwindigkeiten / P. Schuhr (2007)PermalinkTerrain complexity and uncertainties in grid-based digital terrain analysis / Q. Zhou in International journal of geographical information science IJGIS, vol 20 n° 10 (november 2006)PermalinkError assessment in two lidar-derived TIN datasets / M.H. Peng in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 8 (August 2006)PermalinkA comparative study of Australian cartometric and photogrammetric digital elevation model accuracy / J. Walker in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 7 (July 2006)PermalinkExploring the generation of digital elevation from same-side ERS SAR images: topographic and temporal effects / Z. Li in Photogrammetric record, vol 21 n° 114 (June - August 2006)PermalinkSegmentation of airborne laser scanning data using a slope adaptative neighbourhood / S. Filin in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 2 (April 2006)PermalinkÉtude de l'efficacité de l'intégration de la capacité d'infiltration des roches affleurantes dans les modèles spatialisés d'érosion en utilisant la télédétection et le SIG : exemple au Liban / R. Bou Kheir in Photo interprétation, vol 42 n° 1 (Mars 2006)PermalinkThe accuracy of grid digital elevation models linearly constructed from scattered sample data / F. Aguilar in International journal of geographical information science IJGIS, vol 20 n° 2 (february 2006)PermalinkApports de la télédétection et des SIG à la définition de la sensibilité des sols à l'érosion et au suivi de l'occupation du sol sur l'ile d'Anjouan / A. Amir (2006)PermalinkElaboration de MNT par extraction de pentes topographiques de données polarimétriques / Yohann Ly (2006)Permalink