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Orthophoto generation from unorganized point clouds / L. Tournas in Photogrammetric Engineering & Remote Sensing, PERS, vol 73 n° 11 (November 2007)
[article]
Titre : Orthophoto generation from unorganized point clouds Type de document : Article/Communication Auteurs : L. Tournas, Auteur ; M. Tsakiri, Auteur Année de publication : 2007 Article en page(s) : pp 1277 - 1283 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données laser
[Termes IGN] données localisées 3D
[Termes IGN] lasergrammétrie
[Termes IGN] ligne de visée
[Termes IGN] orthoimage
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestre
[Termes IGN] tessellation
[Termes IGN] triangulation de DelaunayRésumé : (Auteur) The reconstruction of realistic precise surfaces is required in many different applications. To date, terrestrial laser scanning offers 3D input data which are suitable for surface generation but are lacking in photo-realistic appearance. Texture for scanned surfaces can be provided by orthophotos generated from photographs that are acquired from almost the same viewpoint as the incident laser beam. However, the creation of an orthophoto using typical photogrammetric procedures requires the representation of the scanned surface with a triangulated mesh which cannot be created automatically in all cases. In this paper, a new method for automatic orthophoto generation from unorganized point clouds is presented. In the proposed methodology, the acquisition of accurate height information is directly derived from the point cloud without the prior requirement of a triangulated mesh. Analysis of experimental data with large height variations demonstrates the success of the algorithm which produces an orthophoto in near real-time. Issues on the performance of the method are also discussed. Copyright ASPRS Numéro de notice : A2007-518 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.73.11.1277 En ligne : http://dx.doi.org/10.14358/PERS.73.11.1277 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28881
in Photogrammetric Engineering & Remote Sensing, PERS > vol 73 n° 11 (November 2007) . - pp 1277 - 1283[article]Unified hybrid terrain representation based on local convexifications / M. Bóo in Geoinformatica, vol 11 n° 3 (September - November 2007)
[article]
Titre : Unified hybrid terrain representation based on local convexifications Type de document : Article/Communication Auteurs : M. Bóo, Auteur ; M. Amor, Auteur ; Jürgen Döllner, Auteur Année de publication : 2007 Article en page(s) : pp 331 - 357 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] imprécision géométrique
[Termes IGN] intégration de données
[Termes IGN] maillage par triangles
[Termes IGN] modèle numérique de terrain
[Termes IGN] relation topologique
[Termes IGN] résolution multiple
[Termes IGN] tessellation
[Termes IGN] Triangulated Irregular NetworkRésumé : (Auteur) Hybrid digital terrain models represent an effective framework to combine and integrate terrain data with different topology and resolution. Cartographic digital terrain models typically are constituted by regular grid data and can be refined by adding locally TINs that represent morphologically complex terrain parts. Direct rendering of both data sets to visualize the digital terrain model would generate geometric discontinuities as the meshes are disconnected. In this paper we present a new meshing scheme for hybrid terrain representations. High quality models without discontinuities are generated as the different representations are softly joined through an adaptive tessellation procedure. Due to the complexity of the algorithms involved in the tessellation procedure, we propose a mixed strategy where part of the information is pre-computed and efficiently encoded. This way, for rendering the model, the tessellation information has to be decoded and only additional simple operations have to be performed. Copyright Springer Numéro de notice : A2007-380 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s10707-006-0003-y En ligne : https://doi.org/10.1007/s10707-006-0003-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28743
in Geoinformatica > vol 11 n° 3 (September - November 2007) . - pp 331 - 357[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-07031 RAB Revue Centre de documentation En réserve L003 Disponible Accuracy of quantized Voronoi diagrams / Yukio Sadahiro in International journal of geographical information science IJGIS, vol 20 n° 10 (november 2006)
[article]
Titre : Accuracy of quantized Voronoi diagrams Type de document : Article/Communication Auteurs : Yukio Sadahiro, Auteur ; T. Tominaga, Auteur Année de publication : 2006 Article en page(s) : pp 1173 - 1189 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] approximation
[Termes IGN] diagramme de Voronoï
[Termes IGN] maille triangulaire
[Termes IGN] objet géographique
[Termes IGN] tessellationRésumé : (Auteur) Quantization of spatial objects, which usually means vector-to-raster conversion in GIS and remote sensing, is a basic operation used for handling spatial data from data creation to visualization. Since quantization is an approximation of spatial objects, it inevitably yields errors in measuring their properties such as area, perimeter, diameter, and so forth. This paper discusses the accuracy of a quantized Voronoi diagram, a spatial tessellation generated from a set of points. A measure is proposed to evaluate the accuracy of the area of Voronoi regions calculated after quantization. In one-dimensional space the measure is expressed as an explicit function of the expected number of generators in a cell. In two-dimensional space, on the other hand, the measure is defined by an implicit function, whose approximation is derived in an explicit form. These functions permit us to evaluate the accuracy of quantization in relation to the size of lattice cells and the density of Voronoi generators. This leads to an appropriate choice of a lattice to keep the quality of a quantized Voronoi diagram at a desirable level. Copyright Taylor & Francis Numéro de notice : A2006-455 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Article DOI : 10.1080/13658810600816748 En ligne : https://doi.org/10.1080/13658810600816748 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28179
in International journal of geographical information science IJGIS > vol 20 n° 10 (november 2006) . - pp 1173 - 1189[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-06101 RAB Revue Centre de documentation En réserve L003 Disponible 079-06102 RAB Revue Centre de documentation En réserve L003 Disponible Method for detecting apparent differences between spatial tessellations at different time points / A. Masuyama in International journal of geographical information science IJGIS, vol 20 n° 6 (july 2006)
[article]
Titre : Method for detecting apparent differences between spatial tessellations at different time points Type de document : Article/Communication Auteurs : A. Masuyama, Auteur Année de publication : 2006 Article en page(s) : pp 633 - 648 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] analyse diachronique
[Termes IGN] appariement de formes
[Termes IGN] appariement de graphes
[Termes IGN] détection de changement
[Termes IGN] fusion de données multisource
[Termes IGN] tessellationRésumé : (Auteur) This paper proposes methods for detecting apparent differences between spatial tessellations at two different points in time, with the objective of conflation of spatial tessellations at multiple time points. The methods comprise three steps. First, we eliminate systematic differences between tessellations using the affine transformation. Second, we match subregions between tessellations at two points in time and match boundaries based on matching relationships between the subregions. Third, we propose a distance metric for measuring differences between the matched boundaries and a method for determining whether the measured differences are apparent or not. We apply the proposed methods to a part of the US Census data for 1990 and 2000 and empirically demonstrate the effectiveness of these methods. Numéro de notice : A2006-238 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810600661300 En ligne : https://doi.org/10.1080/13658810600661300 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27965
in International journal of geographical information science IJGIS > vol 20 n° 6 (july 2006) . - pp 633 - 648[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-06061 RAB Revue Centre de documentation En réserve L003 Disponible 079-06062 RAB Revue Centre de documentation En réserve L003 Disponible
contenu dans Progress in Spatial Data Handling : 12th International Symposium on Spatial Data Handling / Andreas Riedl (2006)
Titre : A Voronoï-based map algebra Type de document : Article/Communication Auteurs : Hugo Ledoux, Auteur ; Christopher Gold, Auteur Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2006 Conférence : SDH 2006, 12th international symposium on Spatial Data Handling 12/07/2006 14/07/2006 Vienne Autriche Proceedings Springer Importance : pp 117 - 131 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] diagramme de Voronoï
[Termes IGN] données localisées 3D
[Termes IGN] Map Algebra
[Termes IGN] tessellationRésumé : (auteur) Although the map algebra framework is very popular within the GIS community for modelling fields, the fact that it is solely based on raster structures has been severely criticised. Instead of representing fields with a regular tessellation, we propose in this paper using the Voronoi diagram (VD), and argue that it has many advantages over other tessellations. We also present a variant of map algebra where all the operations are performed directly on VDs. Our solution is valid in two and three dimensions, and permits us to circumvent the gridding and resampling processes that must be performed with map algebra. Numéro de notice : C2006-005 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Communication DOI : 10.1007/3-540-35589-8_8 En ligne : http://dx.doi.org/10.1007/3-540-35589-8_8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76259 An integrated TIN and Grid method for constructing multi-resolution digital terrain models / B. Yang in International journal of geographical information science IJGIS, vol 19 n° 10 (november 2005)PermalinkTowards a 3D feature overlay through a tetrahedral mesh data structure / Edward Verbree in Cartography and Geographic Information Science, vol 32 n° 4 (October 2005)PermalinkA subdivision algorithm for smooth 3D terrain models / Norbert Pfeifer in ISPRS Journal of photogrammetry and remote sensing, vol 59 n° 3 (May 2005)PermalinkCubic map algebra functions for spatio-temporal analysis / J. Mennis in Cartography and Geographic Information Science, vol 32 n° 1 (January 2005)PermalinkLe procédé de navigation spatiale Transmap (R) : application à l'imagerie territoriale / Franck Perdrizet in Bulletin [Société Française de Photogrammétrie et Télédétection], n° 168 (Octobre 2002)PermalinkGeometric probability and GIS: some applications for the statistics of intersections / A.M. Shortridge in International journal of geographical information science IJGIS, vol 16 n° 3 (april 2002)PermalinkRepresentations of space and time / Donna J. Peuquet (2002)PermalinkGeographical Information Systems, 1. Principles and technical issues / Paul A. Longley (1999)PermalinkPrinciples of Geographical Information Systems / Peter A. Burrough (1998)PermalinkSIG et cartographie / Jean-Paul Cheylan in Bulletin du comité français de cartographie, n° 151 - 152 (mars - août 1997)PermalinkGIS / Michael F. Worboys (1995)PermalinkReprésentation des connaissances pour la mise à jour automatique des Systèmes d'Information Géographique par photos aériennes / Carlo Schenone (1994)PermalinkLes bases de données en géomatique / Robert Laurini (1993)PermalinkFundamentals of spatial information systems / Robert Laurini (1992)PermalinkDigital representations of topographic surfaces / J.R. Carter in Photogrammetric Engineering & Remote Sensing, PERS, vol 54 n° 11 (november 1988)PermalinkApplications cartographiques et numériques de la base de données altimétriques (BDZ) : modèles et produits dérivés [BD ALTI] / C. Pilkiewicz in Bulletin d'information de l'Institut géographique national, n° 54 (janvier 1987)PermalinkA modular system for interpreting binary pixel representations of line-structured data on maps / J.F. Harris in Cartographica, vol 19 n° 2 (June 1982)PermalinkTranscription cartographique des informations spatiales : les différentes modalités disponibles à l'IGN / Jean Denègre (1979)PermalinkRegular density network / L. Ratajski in Annuaire international de cartographie, n° 17 (1977)Permalink