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Measuring the impact of 3D data geometric modeling on spatial analysis : illustration with Skyview factor / Mickaël Brasebin (2012)
Titre : Measuring the impact of 3D data geometric modeling on spatial analysis : illustration with Skyview factor Type de document : Article/Communication Auteurs : Mickaël Brasebin , Auteur ; Julien Perret , Auteur ; Sébastien Mustière , Auteur ; Christiane Weber, Auteur Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2012 Conférence : Usage, Usability, and Utility of 3D City Models – European COST Action TU0801 29/10/2012 31/10/2012 Nantes France OA proceedings Importance : 18 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] analyse spatiale
[Termes IGN] BD Topo
[Termes IGN] données localisées 3D
[Termes IGN] modèle géométrique
[Termes IGN] scène urbaineRésumé : (auteur) The increased availability of 3D urban data reflects a growing interest in 3D spatial analysis. As 3D spatial analysis often uses complex 3D data, studies of the po- tential gains of using more detailed 3D urban databases for specific uses is an important issue. First, more complex data implies an increase in time and memory usage for the analysis (and calls for more research on the efficiency of the algorithms used). Second, detailed 3D urban data are complex to produce, expensive and it is important to be well informed in order to decide whether of not to invest in such data. Currently, many studies have been led about the fitness for use of 2D data but they are very scarce concerning 3D data. This article presents a method to determine the influence of 3D modeling on the results of 3D analysis by isolating the potential sources of errors (such as roof modeling and geometric accuracy). This method is applied on two 3D datasets (LOD1 and LOD2) and a 3D indicator (the sky view factor or SVF). The results show that the significant influence of roof modeling is globally compensated by the difference in geometric modeling but that important local variations are noticed. Nevertheless, for 75% of the SVF processed the difference between the results using these two databases is lower than 2% Numéro de notice : C2012-031 Affiliation des auteurs : LASTIG COGIT+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : 10.1051/3u3d/201202001 En ligne : https://doi.org/10.1051/3u3d/201202001 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101227
contenu dans Proceedings, Commission 3, XXII ISPRS Congress, 25 August – 01 September 2012, Melbourne, Australia / M. Shortis (2012)
Titre : Reconstruction of sky illumination domes from ground-based panoramas Type de document : Article/Communication Auteurs : Fabien Coubard , Auteur ; Lâmân Lelégard , Auteur ; Mathieu Brédif , Auteur ; Nicolas Paparoditis , Auteur ; Xavier Briottet , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2012 Collection : International Archives of Photogrammetry and Remote Sensing, ISSN 0252-8231 num. 39-B3 Conférence : ISPRS 2012, Commission 3, 22th international congress 25/08/2012 01/09/2012 Melbourne Australie OA ISPRS Archives Commission 3 Importance : pp 269 - 274 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] correction radiométrique
[Termes IGN] éclairement lumineux
[Termes IGN] image terrestre
[Termes IGN] panorama sphérique
[Termes IGN] radiance
[Termes IGN] scène urbaineRésumé : (auteur) The knowledge of the sky illumination is important for radiometric corrections and for computer graphics applications such as relighting or augmented reality. We propose an approach to compute environment maps, representing the sky radiance, from a set of ground-based images acquired by a panoramic acquisition system, for instance a mobile-mapping system. These images can be affected by important radiometric artifacts, such as bloom or overexposure. A Perez radiance model is estimated with the blue sky pixels of the images, and used to compute additive corrections in order to reduce these radiometric artifacts. The sky pixels are then aggregated in an environment map, which still suffers from discontinuities on stitching edges. The influence of the quality of estimated sky radiance on the simulated light signal is measured quantitatively on a simple synthetic urban scene; in our case, the maximal error for the total sensor radiance is about 10%. Numéro de notice : C2012-015 Affiliation des auteurs : LASTIG MATIS (2012-2019) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/isprsarchives-XXXIX-B3-23-2012 En ligne : http://dx.doi.org/10.5194/isprsarchives-XXXIX-B3-269-2012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94278
contenu dans Photogrammetric image analysis PIA 11, Munich, Germany, October 5-7, 2011 / Uwe Stilla (2011)
Titre : Fast and accurate visibility computation in urban scenes Type de document : Article/Communication Auteurs : Bruno Vallet , Auteur ; Erwann Houzay, Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2011 Collection : International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, ISSN 1682-1750 num. 38-3/W22 Conférence : PIA 2011, ISPRS Conference on Photogrammetric Image Analysis 05/10/2011 07/10/2011 Munich Allemagne OA ISPRS Archives Importance : pp 77 - 82 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] bâtiment
[Termes IGN] façade
[Termes IGN] géomètrie algorithmique
[Termes IGN] modèle 3D de l'espace urbain
[Termes IGN] processeur graphique
[Termes IGN] rastérisation
[Termes IGN] scène urbaine
[Termes IGN] texturage
[Termes IGN] visibilité entre pointsRésumé : (auteur) This paper presents a method to efficiently compute the visibility of a 3D model seen from a series of calibrated georeferenced images. This is required to make methods aimed at enriching 3D models (finer reconstruction, texture mapping) based on such images scalable. The method consists in rasterizing the scene on the GPU from the point of views of the images with a known mapping between colors and scene elements. This pixel based visibility information is then made higher level by defining a set of geometric rules to select which images should be used when focusing on a given scene element. The visibility relation is finally used to build a visibility graph allowing for efficient sequential processing of the whole scene. Numéro de notice : C2011-038 Affiliation des auteurs : MATIS (1993-2011) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/isprsarchives-XXXVIII-3-W22-77-2011 Date de publication en ligne : 26/04/2013 En ligne : https://doi.org/10.5194/isprsarchives-XXXVIII-3-W22-77-2011 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92343 Documents numériques
en open access
Fast and accurate visibility... - pdf éditeurAdobe Acrobat PDF Reflectance estimation from urban terrestrial images: validation of a symbolic ray-tracing method on synthetic data / Fabien Coubard (2011)
contenu dans Photogrammetric image analysis PIA 11, Munich, Germany, October 5-7, 2011 / Uwe Stilla (2011)
Titre : Reflectance estimation from urban terrestrial images: validation of a symbolic ray-tracing method on synthetic data Type de document : Article/Communication Auteurs : Fabien Coubard , Auteur ; Mathieu Brédif , Auteur ; Nicolas Paparoditis , Auteur ; Xavier Briottet , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2011 Collection : International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, ISSN 1682-1750 num. 38-3/W22 Conférence : PIA 2011, ISPRS Conference on Photogrammetric Image Analysis 05/10/2011 07/10/2011 Munich Allemagne OA ISPRS Archives Importance : pp 71 - 76 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] correction radiométrique
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] éclairement lumineux
[Termes IGN] image numérique
[Termes IGN] image terrestre
[Termes IGN] itération
[Termes IGN] lancer de rayons
[Termes IGN] modèle géométrique de prise de vue
[Termes IGN] problème inverse
[Termes IGN] réflectance spectrale
[Termes IGN] scène urbaineRésumé : (auteur) Terrestrial geolocalized images are nowadays widely used on the Internet, mainly in urban areas, through immersion services such as Google Street View. On the long run, we seek to enhance the visualization of these images. For that purpose, radiometric corrections must be performed to free them from illumination conditions at the time of acquisition. Given the simultaneously acquired 3D geometric model of the scene with LIDAR or vision techniques, we face an inverse problem where the illumination and the geometry of the scene are known and the reflectance of the scene is to be estimated. Our main contribution is the introduction of a symbolic ray-tracing rendering to generate parametric images, for quick evaluation and comparison with the acquired images. The proposed approach is then based on an iterative estimation of the reflectance parameters of the materials, using a single rendering pre-processing. We validate the method on synthetic data with linear BRDF models and discuss the limitations of the proposed approach with more general non-linear BRDF models. Numéro de notice : C2011-037 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/isprsarchives-XXXVIII-3-W22-71-2011 Date de publication en ligne : 26/04/2013 En ligne : https://doi.org/10.5194/isprsarchives-XXXVIII-3-W22-71-2011 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92341 Documents numériques
en open access
Reflectance estimation... - pdf éditeurAdobe Acrobat PDF Insertion of 3-D-primitives in mesh-based representations: Towards compact models preserving the details / Florent Lafarge in IEEE Transactions on image processing, vol 19 n° 7 (July 2010)
[article]
Titre : Insertion of 3-D-primitives in mesh-based representations: Towards compact models preserving the details Type de document : Article/Communication Auteurs : Florent Lafarge, Auteur ; Renaud Keriven, Auteur ; Mathieu Brédif , Auteur Année de publication : 2010 Article en page(s) : pp 1683 - 1694 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] approche hiérarchique
[Termes IGN] carte de profondeur
[Termes IGN] information sémantique
[Termes IGN] maille triangulaire
[Termes IGN] modèle 3D de l'espace urbain
[Termes IGN] primitive géométrique
[Termes IGN] scène urbaineRésumé : (auteur) We propose an original hybrid modeling process of urban scenes that represents 3-D models as a combination of mesh-based surfaces and geometric 3-D-primitives. Meshes describe details such as ornaments and statues, whereas 3-D-primitives code for regular shapes such as walls and columns. Starting from an 3-D-surface obtained by multiview stereo techniques, these primitives are inserted into the surface after being detected. This strategy allows the introduction of semantic knowledge, the simplification of the modeling, and even correction of errors generated by the acquisition process. We design a hierarchical approach exploring different scales of an observed scene. Each level consists first in segmenting the surface using a multilabel energy model optimized by -expansion and then in fitting 3-D-primitives such as planes, cylinders or tori on the obtained partition where relevant. Experiments on real meshes, depth maps and synthetic surfaces show good potential for the proposed approach. Numéro de notice : A2010-662 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TIP.2010.2045695 Date de publication en ligne : 15/03/2010 En ligne : https://doi.org/10.1109/TIP.2010.2045695 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91762
in IEEE Transactions on image processing > vol 19 n° 7 (July 2010) . - pp 1683 - 1694[article]PermalinkA two-pass random forests classification of airborne Lidar and image data on urban scenes / Li Guo (2010)PermalinkICARE: A physically-based model to correct atmospheric and geometric effects from high spatial and spectral remote sensing images over 3D urban areas / Sophie Lacherade in Meteorology and Atmospheric Physics, vol 102 n° 3-4 (December 2008)PermalinkInterprétation de scènes urbaines à partir d'images satellitaires THR : reconstruction de facettes 3D et optimisation globale 3D / Nesrine Chehata in Bulletin d'information scientifique et technique de l'IGN, n° 75 (mars 2006)PermalinkSpectral variability and bidirectional reflectance behaviour of urban materials at a 20 cm spatial resolution in the visible and near‐infrared wavelengths. A case study over Toulouse (France) / Sophie Lacherade in International Journal of Remote Sensing IJRS, vol 26 n° 17 (September 2005)PermalinkReconstruction de primitives linéaires 3D en multi-vues pour la modélisation de scènes urbaines / Franck Taillandier (2002)PermalinkAutomatic extraction and modelling of urban buildings from high resolution aerial images / Matthieu Cord (1999)PermalinkReconstruction tridimensionnelle de paysages urbains en imagerie stéréoscopique haute résolution / Nicolas Paparoditis (1998)PermalinkUtilisation conjointe d'informations symboliques et de mesures numériques dans la prise de décision en traitement d'images / Henri Moissinac-Massenat (1996)PermalinkAnalyse stéréoscopique de photographies aériennes. Elaboration d'une description volumique des scènes / Michel Jordan (1992)Permalink