Descripteur
Documents disponibles dans cette catégorie (66)
![](./images/expand_all.gif)
![](./images/collapse_all.gif)
![Tris disponibles](./images/orderby_az.gif)
Etendre la recherche sur niveau(x) vers le bas
Streamed vertical rectangle detection in terrestrial laser scans for facade database / Jérôme Demantké in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol I-3 (2012)
![]()
[article]
Titre : Streamed vertical rectangle detection in terrestrial laser scans for facade database Type de document : Article/Communication Auteurs : Jérôme Demantké , Auteur ; Bruno Vallet
, Auteur ; Nicolas Paparoditis
, Auteur
Année de publication : 2012 Article en page(s) : pp 99 - 104 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] chevauchement
[Termes IGN] détection d'objet
[Termes IGN] échantillonnage de données
[Termes IGN] façade
[Termes IGN] fusion d'images
[Termes IGN] Ransac (algorithme)
[Termes IGN] reconnaissance de formesRésumé : (auteur) A reliable and accurate facade database would be a major asset in applications such as localization of autonomous vehicles, registration and fine building modeling. Mobile mapping devices now provide the data required to create such a database, but efficient methods should be designed in order to tackle the enormous amount of data collected by such means (a million point per second for hours of acquisition). Another important limitation is the presence of numerous objects in urban scenes of many different types. This paper proposes a method that overcomes these two issues:
• The facade detection algorithm is streamed : the data is processed in the order it was acquired. More precisely, the input data is split into overlapping blocks which are analysed in turn to extract facade parts. Close overlapping parts are then merged in order
• The geometry of the neighborhood of each point is analysed to define a probability that the point belongs to a vertical planar patch. This probability is then injected in a RANdom SAmple Consensus (RANSAC) algorithm both in the sampling step and in the hypothesis validation, in order to favour the most reliable candidates. This ensures much more robustness against outliers during the facade detection.
This way, the main vertical rectangles are detected without any prior knowledge about the data. The only assumptions are that the facades are roughly planar and vertical. The method has been successfully tested on a large dataset in Paris. The facades are detected despite the presence of trees occluding large areas of some facades. The robustness and accuracy of the detected facade rectangles makes them useful for localization applications and for registration of other scans of the same city or of entire city models.Numéro de notice : A2012-763 Affiliation des auteurs : LASTIG MATIS (2012-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/isprsannals-I-3-99-2012 Date de publication en ligne : 20/07/2012 En ligne : https://doi.org/10.5194/isprsannals-I-3-99-2012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101275
in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences > vol I-3 (2012) . - pp 99 - 104[article]
Titre : Automatic sampling of geographic objects Type de document : Article/Communication Auteurs : Patrick Taillandier , Auteur ; Julien Gaffuri
, Auteur
Editeur : Saint-Mandé : Institut Géographique National - IGN (2008-2011) Année de publication : 2010 Conférence : GIScience 2010, 6th international conference on geographic information science 14/09/2010 17/09/2010 Zurich Suisse Proceedings Springer Importance : 6 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] échantillonnage de données
[Termes IGN] objet géographiqueRésumé : (auteur) [introduction] The numeric revolution hada deep impact on the use of geographic data. Today, one’s can have access to numerous large datasets that are composed of thousands of geographic objects. However, many geographical processes require the use of only a small sample of data. The method used to choose the geographical objects has to be considered. In this paper, we propose approach dedicated to the selection of a sample of geographic objects. Section 2 presents the context of this work. In section 3, the sampling method we propose is described. Section 4 is dedicated to the evaluation of our method. Numéro de notice : C2010-040 Affiliation des auteurs : COGIT+Ext (1988-2011) Autre URL associée : vers HAL Thématique : GEOMATIQUE/INFORMATIQUE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : https://hal.science/hal-00689137v1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95963 Documents numériques
peut être téléchargé
Automatic sampling of geographic objects - pdf éditeurAdobe Acrobat PDFContour line thinning and multigrid generation of raster-based digital elevation models / E. Katona in International journal of geographical information science IJGIS, vol 21 n° 1-2 (january 2007)
![]()
[article]
Titre : Contour line thinning and multigrid generation of raster-based digital elevation models Type de document : Article/Communication Auteurs : E. Katona, Auteur Année de publication : 2007 Article en page(s) : pp 71 - 82 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] contour
[Termes IGN] données matricielles
[Termes IGN] échantillonnage de données
[Termes IGN] fonction spline d'interpolation
[Termes IGN] modèle numérique de surfaceRésumé : (Auteur) Thin plate spline interpolation is a widely used approach to generate a digital elevation model (DEM) from contour lines and scattered data. In practice, contour maps are scanned and vectorized, and after resampling in the target grid resolution, interpolation is performed. In this paper we demonstrate the limited accuracy of this process, and propose a high-resolution processing method (without vectorization) that ensures maximum utilization of information in the source data. First, we discuss the mathematical background of thin plate spline interpolation, and explain the multigrid relaxation principle used to speed up convergence. After, we will show why fine tuning is necessary, especially when contour lines and elevation points are processed at the same time. Finally, our own contour thinning method that produces a significant reduction of elevation bias is described. Copyright Taylor & Francis Numéro de notice : A2007-026 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/13658810600816474 En ligne : https://doi.org/10.1080/13658810600816474 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28392
in International journal of geographical information science IJGIS > vol 21 n° 1-2 (january 2007) . - pp 71 - 82[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-07011 RAB Revue Centre de documentation En réserve L003 Disponible 079-07012 RAB Revue Centre de documentation En réserve L003 Disponible The 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)
![]()
[article]
Titre : The accuracy of grid digital elevation models linearly constructed from scattered sample data Type de document : Article/Communication Auteurs : F. Aguilar, Auteur ; M. Aguilar, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 169 - 192 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] couple stéréoscopique
[Termes IGN] écart type
[Termes IGN] échantillonnage de données
[Termes IGN] erreur d'échantillon
[Termes IGN] erreur moyenne quadratique
[Termes IGN] image aérienne
[Termes IGN] interpolation linéaire
[Termes IGN] maille carrée
[Termes IGN] modèle numérique de surface
[Termes IGN] modélisation 3D
[Termes IGN] pente
[Termes IGN] propagation d'erreur
[Termes IGN] rugosité du sol
[Termes IGN] système d'information géographiqueRésumé : (Auteur) In this paper, a theoretical-empirical model is developed for modelling the accuracy of a grid digital elevation model (DEM) linearly constructed from scattered sample data. The theoretical component integrates sample data accuracy in the model by means of the error-propagation theory. The empirical component seeks to model what is known as information loss, i.e. the sum of the error due purely to sampling the continuous terrain surface with a finite grid interval and the interpolation error. For this purpose, randomly spaced data points, supposed to be free of error, were converted into regularly gridded data points using triangulation with linear interpolation. Original sample data were collected with a 2 x 2 m sampling interval from eight different morphologies, from flat terrain to highly rugged terrain, applying digital photogrammetric methods to large-scale aerial stereo imagery (1 :5000). The DEM root mean square error was calculated by the true validation method over several sets of check points, obtaining the different sampling densities tested in this work. Several empirical models are calibrated and validated with the experimental data set by modelling the DEM accuracy by combining two variables such as sampling density and a descriptive attribute of terrain morphology. These empirical models presented a morphology based on the product of two potential functions, one related to the terrain roughness and another related to the sampling density. The terrain descriptors tested were average terrain slope, standard deviation of terrain slope, standard deviation of unitary vectors perpendicular to the topographic surface (SDUV), standard deviation of the difference in height between adjacent samples in the grid DEM (SDHD), and roughness estimation by first-, second-, or third-degree surface fitting error. The values obtained for those terrain descriptors were reasonably independent from the number and spatial distribution of the sample data. The models based on descriptors SDHD, SDUV, and standard deviation of slope provided a good fitting to the data observed (R 2> 0.94) in the calibration phase, model SDHD being the one that yielded the best results in validation. Therefore, it would be possible to establish a priori the optimum grid size required to generate or store a DEM of a particular accuracy, with the saving in computing time and file size that this would mean for the digital flow of the mapping information in GIS. Numéro de notice : A2006-066 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/13658810500399670 En ligne : https://doi.org/10.1080/13658810500399670 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27793
in International journal of geographical information science IJGIS > vol 20 n° 2 (february 2006) . - pp 169 - 192[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-06021 RAB Revue Centre de documentation En réserve L003 Disponible 079-06022 RAB Revue Centre de documentation En réserve L003 Disponible
[article]
Titre : Méthodes de suivi géométrique Type de document : Article/Communication Auteurs : Michel Kasser , Auteur
Année de publication : 2003 Article en page(s) : pp 44 - 47 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] échantillonnage de données
[Termes IGN] effondrement de terrain
[Termes IGN] grotte
[Termes IGN] image radar moirée
[Termes IGN] positionnement par GPS
[Termes IGN] précision centimétrique
[Termes IGN] risque majeur
[Termes IGN] télémétrie laser
[Termes IGN] topométrie de précisionRésumé : (Auteur) Le projet RESUM (Réseau de Suivi de Subsidence Urbaine et Minière) a pour but de développer un action sur la mesure des phénomènes de déformation du sol (affaissements miniers, cavités naturelles, ouvrages souterrains, exploitation des nappes phréatiques) par le biais de l'interférométrie radar (http://resum.brgm.fr). Il implique notamment des organismes publics (BRGM, IGN, LCPC, ECP, CNES) et des utilisateurs industriels (Gaz de France et Groupe Charbonnages de France). Numéro de notice : A2003-058 Affiliation des auteurs : IGN (1940-2011) Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78907
in Géomètre > vol 2003 n° 4 (avril 2003) . - pp 44 - 47[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 063-03042 RAB Revue Centre de documentation En réserve L003 Disponible Un générateur de données bathymétriques pour l'aide au prétraitement des cartes marines / R. Thibaudeau in Revue internationale de géomatique, vol 12 n° 3 (septembre - novembre 2002)
PermalinkTopologically consistent line simplification with the Douglas-Peucker algorithm / A. Saalfeld in Cartography and Geographic Information Science, vol 26 n° 1 (January 1999)
PermalinkInitiation aux pratiques statistiques en géographie, 4e édition entièrement refondue / Groupe Chadule (1997)
PermalinkModélisation, exploitation et visualisation de l'information qualité dans les bases de données géographiques / S.O. Faiz (1996)
PermalinkPermalinkPermalinkThe application of Radon transformation for improved analysis of sparsely sampled data / R.H. Hanssen (1993)
PermalinkEchantillonnage optimal pour modèle numérique de terrain, partie intégrante d'un système d'information géographique, Volume 1. Thèse / Massoud Charif (1991)
PermalinkEchantillonnage optimal pour modèle numérique de terrain, partie intégrante d'un système d'information géographique, Volume 2. Annexes / Massoud Charif (1991)
PermalinkPermalink