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Titre : Classification of roof materials for rainwater pollution modelization Type de document : Article/Communication Auteurs : Arnaud Le Bris , Auteur ; Pauline Robert-Sainte, Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2009 Conférence : ISPRS 2009, High-Resolution Earth Imaging for Geospatial Information workshop 02/06/2009 05/06/2009 Hanovre Allemagne OA ISPRS Archives Importance : 6 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] BD Topo
[Termes IGN] classification dirigée
[Termes IGN] eau pluviale
[Termes IGN] image RVB
[Termes IGN] matériau
[Termes IGN] milieu urbain
[Termes IGN] ombre
[Termes IGN] orthoimage couleur
[Termes IGN] pollution des eaux
[Termes IGN] segmentation d'image
[Termes IGN] toitRésumé : (Auteur) It has been proven that roof runoff water plays an important role in the high metallic concentration levels in urban rainwater since metallic elements are generated by corrosion of roof materials before being swept away by rainwater. The aim of TOITEAU project is therefore to model this phenomenon, evaluating the metallic flows from roofs in rainwater. To achieve this goal, an important work has already been done to model those flows at roof scale. But, it has now to be extrapolated to a whole drainage area, requiring knowledge about the areas concerned by the different kinds of roof coverage, that is to say that a map of roof materials is needed. Such information can be extracted from aerial (ortho) images owing to (supervised) classification techniques. In the present situation, only six classes corresponding to the following kinds of roofs were defined : zinc plates, slates, red tiles, brown tiles and flat roofs. Nevertheless, classification results are limited because of several factors that have therefore to be dealt with. First of all, some distinct classes have very similar radiometric distribution (such as for instance zinc and at light slates), making it hard to distinguish between them. That's why derived channels computed from initial red-green-blue channels of the ortho-image have been used to improve the classification results. Texture channels have also been tested especially to discriminate zinc from other light coloured roof materials. For the same reason and in order not to obtain a too ”noisy” result, per region classification algorithms have been used : homogeneous regions will be classified instead of pixels. Secondly, roofs are the only interesting parts of the ortho-image in this study. As a consequence, a building mask is first computed from digital topographic database BDTopo in order to classify only roofs. However, several elements concerning data precision have to be taken into account at this step. For instance, the ortho-image and the topographic database can obviously not have been captured at the same date and, as a consequence, buildings can have been destroyed, modified or built between these two distinct capture times. In addition, as the used ortho-image is not a ”true ortho-image”, building objects from digital topographic database and ortho-image roofs are not perfectly superposed. However, these topographic database building objects can be registered to the ortho-image. Nevertheless, it must be said that these database objects often remain caricatures of true buildings. Besides, most of the time, homogeneous regions to be classified do not directly correspond to database buildings since those database objects can be groups of buildings or buildings of which the roof is composed of different materials. Therefore, it is necessary to segment building areas (according to the topographic database) of the ortho-image into homogeneous regions that are then classified. Lastly, shadows can be quite important in roof areas because of the presence of roof superstructures or higher buildings in the neighbourhood. That's why an additional class ”shadow” is also defined in order to take into account shadow areas where radiometric information is not sufficient to discriminate between the different kinds of materials. Tests have been carried out on two distinct study areas with 50cm resolution orthophotos for the first one and 12cm resolution orthoimages for the second one. The first study area was a dense urban centre, whereas the second could be divided into several parts : a residential suburb consisting of houses, a dense urban centre with buildings having up to 4-5 levels and a mixed residential / service area consisting of higher buildings. Numéro de notice : C2009-038 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : https://www.isprs.org/proceedings/XXXVIII/1_4_7-W5/paper/LE_BRIS-152.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64298 Documents numériques
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Classification of roof materials ... - pdf éditeurAdobe Acrobat PDF Extraction of land cover themes from aerial ortho-images in mountainous areas using external information / Arnaud Le Bris in Photogrammetric record, vol 23 n° 124 (December 2008 - February 2009)
[article]
Titre : Extraction of land cover themes from aerial ortho-images in mountainous areas using external information Type de document : Article/Communication Auteurs : Arnaud Le Bris , Auteur ; Didier Boldo , Auteur Année de publication : 2008 Conférence : ISPRS 2007, High-Resolution Earth Imaging for Geospatial Information workshop 29/05/2007 01/06/2007 Hanovre Allemagne OA ISPRS Archives Article en page(s) : pp 387 - 404 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] extraction automatique
[Termes IGN] image aérienne
[Termes IGN] montagne
[Termes IGN] occupation du sol
[Termes IGN] ombre
[Termes IGN] orthoimage
[Termes IGN] valeur radiométriqueRésumé : (Auteur) In mountainous areas, land cover extraction from ortho-images through semi-automatic classification techniques is limited by several factors including large shadow areas, radiometric similarities between distinct themes and inhomogeneous radiometry among regions of the same class. The information in the image is thus not sufficient to separate the different classes. Nevertheless, good results can be obtained by dividing each land cover class into two subclasses, "shadow" and "non-shadow", and introducing external information into the classification process. This information can be derived from an older or more generalised database, geographical knowledge concerning the links between relief and land cover, or prior information concerning shadows. This external knowledge is then interpreted in terms of prior probabilities and merged with radiometric information from the image in a "maximum a posteriori (MAP) per region" classification process. Moreover, the results can also be improved by the use of combinations of derived channels calculated from the initial spectral bands of the image. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2008-419 Affiliation des auteurs : MATIS (1993-2011) Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2008.00502.x Date de publication en ligne : 24/11/2008 En ligne : https://doi.org/10.1111/j.1477-9730.2008.00502.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29490
in Photogrammetric record > vol 23 n° 124 (December 2008 - February 2009) . - pp 387 - 404[article]Interactive responses of Quercus suber L. seedlings to light and mild water stress: effects on morphology and gas exchange traits / Jaime Puértolas in Annals of Forest Science, Vol 65 n° 6 (September 2008)
[article]
Titre : Interactive responses of Quercus suber L. seedlings to light and mild water stress: effects on morphology and gas exchange traits Titre original : Réponses interactives de semis de Quercus suber L. à la lumière et à un stress hydrique modéré : effets sur la morphologie et sur les caractéristiques des échanges gazeux Type de document : Article/Communication Auteurs : Jaime Puértolas, Auteur ; Marta Pardos, Auteur ; María Dolores Jiménez, Auteur ; Ismael Aranda, Auteur ; José Alberto Pardos, Auteur Année de publication : 2008 Article en page(s) : n° 611 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] diagnostic foliaire
[Termes IGN] ombre
[Termes IGN] photosynthèse
[Termes IGN] Quercus suber
[Termes IGN] stress hydriqueRésumé : (auteur) The combined effect of water stress and light on seedlings of forest species is a key factor to determine the best silvicultural and afforestation practices in the Mediterranean area. The aims of this work was (1) to determine the optimal light level for the early development of cork oak seedlings under mild water stress and (2) to test if the combined effect of water stress and light followed the trade-off, the facilitation or the orthogonal hypothesis. Shade reduced instantaneous photosynthetic rates and water use efficiency in cork oak. However, seedlings grown under moderate shade (15% of full sunlight) were capable to accumulate similar amount of biomass than those grown under more illuminated environments by increasing their specific leaf area. Absolute differences in net photosynthesis between light treatments were higher in well watered than in water stressed seedlings. However, the impact of both factors on overall growth was orthogonal. We concluded that cork oak development is impaired under deep shade (5% of full sunlight) but it can be optimal under moderate shade (15% of full sunlight) even under moderate water stress. Implications of these patterns on regeneration, cultivation and afforestation of cork oak are discussed. Numéro de notice : A2008-698 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1051/forest:2008044 Date de publication en ligne : 04/09/2008 En ligne : https://www.afs-journal.org/articles/forest/abs/2008/06/f08038/f08038.html Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=70784
in Annals of Forest Science > Vol 65 n° 6 (September 2008) . - n° 611[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité IFN-DIR-P000123 PER Revue Nogent-sur-Vernisson Salle périodiques Exclu du prêt Integrated use of SRM, Landsat ETM+ data and 3D perspective views to identify the tectonic geomorphology of Dehradun valley, India / A.K. Singh in International Journal of Remote Sensing IJRS, vol 28 n°11-12 (June 2007)
[article]
Titre : Integrated use of SRM, Landsat ETM+ data and 3D perspective views to identify the tectonic geomorphology of Dehradun valley, India Type de document : Article/Communication Auteurs : A.K. Singh, Auteur ; B. Parkash, Auteur ; P.R. Choudhury, Auteur Année de publication : 2007 Article en page(s) : pp 2403 - 2414 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] carte géomorphologique
[Termes IGN] géomorphologie locale
[Termes IGN] image Landsat-ETM+
[Termes IGN] Inde
[Termes IGN] modèle numérique de terrain
[Termes IGN] ombre
[Termes IGN] perspective
[Termes IGN] tectonique
[Termes IGN] vallée
[Termes IGN] visualisation 3DRésumé : (Auteur) The present study aims to develop an integrated shaded relief model (SRM), remote sensing image and three-dimensional (3D) perspective view based approach for delineating tectonic geomorphology of the Dehradun Intermontane valley, India. SRM created from digital elevation model (DEM) actually represents the information of the bare ground surface without any surface cover such as vegetation and landuse. Under user-specified positions of the sun, this was useful in enhancing the lineaments. This, coupled with Landsat ETM+ data and 3D perspective views has proven to be a very good tool for the identification of geological features. In a hilly terrain, like the present area, having dense forest cover, many places are inaccessible and geological field mapping is quite difficult. This approach successfully identified tectonic geomorphological features like faults, alluvial fans and terraces in the present area. Comparison of the identified faults and geomorphic features with published work and field checks reveals that this method of mapping can reduce the time and effort required in fieldwork to a large extent. Numéro de notice : A2007-308 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160600993397 En ligne : https://doi.org/10.1080/01431160600993397 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28671
in International Journal of Remote Sensing IJRS > vol 28 n°11-12 (June 2007) . - pp 2403 - 2414[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-07071 RAB Revue Centre de documentation En réserve L003 Disponible Extraction of landcover themes out of aerial orthoimages in mountainous areas using external information / Arnaud Le Bris (2007)
Titre : Extraction of landcover themes out of aerial orthoimages in mountainous areas using external information Type de document : Article/Communication Auteurs : Arnaud Le Bris , Auteur ; Didier Boldo , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2007 Collection : International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, ISSN 1682-1750 num. 36-3-W49 Conférence : PIA 2007, ISPRS Conference on Photogrammetric Image Analysis 19/09/2007 21/09/2007 Munich Allemagne ISPRS OA Archives Importance : pp 123 - 128 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] actualité des données
[Termes IGN] base de données localisées IGN
[Termes IGN] carte de base
[Termes IGN] classification basée sur les régions
[Termes IGN] équilibrage radiométrique
[Termes IGN] extraction de la végétation
[Termes IGN] fusion d'images
[Termes IGN] image aérienne
[Termes IGN] incertitude géométrique
[Termes IGN] modèle numérique de terrain
[Termes IGN] montagne
[Termes IGN] occupation du sol
[Termes IGN] ombre
[Termes IGN] orthoimage
[Termes IGN] relief
[Termes IGN] valeur radiométriqueRésumé : (auteur) In mountainous areas, the landcover extraction out of orthoimages through semi-automatic classification is limited by several factors (such as large shadow areas, radiometric similarities between different themes, inhomogeneous radiometry among regions of the same class...). Image information is not sufficient to separate the different classes. Nevertheless, good results can be obtained by dividing each landcover class “c” into two subclasses “c in shadow” / “c not in shadow” and introducing external information in the classification process. This information can be an older or more generalized database, geographic knowledge concerning the links between relief and landcover, or prior information concerning shadows. This external knowledge is then interpreted in terms of a priori probabilities and merged with radiometric information from the image in a MAP per region classification process. Besides, the results can also be improved by the use of combinations of channels calculated from the initial image. Numéro de notice : C2007-032 Affiliation des auteurs : MATIS (1993-2011) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : https://www.isprs.org/proceedings/XXXVI/3-W49/PartA/papers/123_pia07.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92362 Documents numériques
en open access
Extraction of landcover... - pdf éditeurAdobe Acrobat PDF Applying 3D city models, intervisibility, LBS, sunlight/shadow analysis, air and noise pollution / C.L. Wu in GIM international, vol 20 n° 2 (February 2006)PermalinkA uniform sky illumination model to enhance shading of terrain and urban areas / Patrick Kennelly in Cartography and Geographic Information Science, vol 33 n° 1 (January 2006)PermalinkEstimating sub-pixel surface roughness using remotely sensed stereoscopic data / A. Mushkin in Remote sensing of environment, vol 99 n° 1-2 (15 November 2005)PermalinkIntegrated shadow removal based on photogrammetry and image analysis / Y. Li in International Journal of Remote Sensing IJRS, vol 26 n° 18 (September 2005)PermalinkCloud-free satellite image mosaics with regression trees and histogram matching / E.H. Helmert in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 9 (September 2005)PermalinkProblèmes relatifs aux ombres d'objets élevés sur les photographies aériennes / Raymond d' Hollander in XYZ, n° 104 (septembre - novembre 2005)PermalinkTopographic information of sand dunes as extracted from shading effects using Landsat images / N. Levin in Remote sensing of environment, vol 90 n° 2 (30/03/2004)PermalinkEffets radiométriques en milieu urbain à grande échelle et correction des ombres / Gilles Martinoty in Géomatique expert, n° 32 (01/03/2004)PermalinkPhenomenological analysis of simulated signals observed over shaded areas in an urban scene / Christophe Miesch in IEEE Transactions on geoscience and remote sensing, vol 42 n° 2 (February 2004)PermalinkFabrication de vraies ortho-images et correction des ombres / Didier Boldo in Bulletin d'information scientifique et technique de l'IGN, n° 74 (mars 2003)Permalink