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Fusion of hyperspectral images and digital surface models for urban object extraction / Janja Avbelj (2016)
Titre : Fusion of hyperspectral images and digital surface models for urban object extraction Type de document : Thèse/HDR Auteurs : Janja Avbelj, Auteur ; Xiaoxiang Zhu, Directeur de thèse Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2016 Collection : DGK - C, ISSN 0065-5325 num. 771 Importance : 143 p. ISBN/ISSN/EAN : 978-3-7696-5183-6 Note générale : bibliographie
PhD DissertationLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] classification bayesienne
[Termes IGN] détection d'objet
[Termes IGN] extraction automatique
[Termes IGN] fusion de données
[Termes IGN] image hyperspectrale
[Termes IGN] modèle numérique de surface
[Termes IGN] optimisation (mathématiques)
[Termes IGN] polygone
[Termes IGN] rectangle englobant minimumRésumé : (auteur) Buildings are prominent objects of the constantly changing urban environment. Accurate and up to date Building Polygons (BP) are needed for a variety of applications, e.g. 3D city visualisation, micro climate forecast, and real estate databases. The increasing number of earth observation remote sensing images enables the development of methods for building extraction. For instance, Hyperspectral Images (HSI) are a source of information about the material of the objects in the scene, whereas the Digital Surface Models (DSM) carry information about height of the surface and of objects. Thus, complementary information from multi-modal images, such as HSI and DSM, is needed to provide better understanding of the observed objects. A variation in material and height is represented by an edge in HSI and DSM, respectively. Edges in an image carry large portions of information about the geometry of the objects, because they delineate the boundaries between them. Object extraction and delineation is more reliable if information content from HSI, DSM, and edge information is jointly accounted for. The focus in this thesis is on method development for BP extraction using complementary information from HSI and DSM by accounting for edge information. Furthermore, a new quality measure, which accounts for shape differences and geometric accuracy between extracted and reference polygons, is proposed. Object and edge detection from an image is meaningful only for some range of scales. Edge detection in scale space is motivated by showing that in the same image different edges appear at different scales. Instead of deterministic edge detection, edge probabilities are computed in a linear scale space. Bayesian fusion of edge probabilities is proposed, which employs a Gaussian mixture model. The scale, at which an edge probability is computed, is defined by a confidence probability. The impact of selecting mixing coefficients in the Gaussian mixture model according to a prior knowledge or by a fully automatic data-driven approach is investigated. Main limitations of joining the edge probabilities from different datasets are the coregistration between the datasets and the inaccuracies in the datasets. The rectilinear BP are adjusted by means of weighted least squares, where the weights are defined on the basis of joint edge probabilities. Two mathematical models for rectilinear BP are proposed, one with a strict rectilinearity constraint and the second one, which introduces a relaxed rectilinearity constraint through weighting. The experiments on synthetic images show that the model with strict constraint gives better results, if the BP under consideration are all rectilinear. Otherwise, the relaxed rectilinearity constraint through weighting balances better between the rectilinearity assumption and fitness to the data. The approximate BP are created by a Minimum Bounding Rectangle (MBR) method. A main contribution of the proposed iterative MBR method is the automatic selection of a level of complexity of MBR through analysis of a cost function. A metric for comparison of polygons and line segments, named PoLiS metric, is defined. It compares polygons with different number of vertices, is insensitive to the number of vertices on polygon's edges, is monotonic, and has a nearly linear response to small changes in translation, rotation, and scale. Its characteristics are discussed and compared to the commonly used measures for BP evaluation. In all experiments the BP are evaluated by computing the newly proposed PoLiS metric and quality rate. The feasibility of joining all the proposed methods in one workflow is shown through the experiment, which is carried out on 17 HSI-DSM dataset pairs with four different ground sampling distances. The main finding of the experiment is that joining the information from multi-modal images, i.e. HSI and DSM, results in better quality of the adjusted BP. For instance, even for datasets with 4 m ground sampling distance, the completeness, correctness and quality rate values of extracted BP are better than 0.83, 0.68, and 0.60. Inaccuracies of the images, such as holes in DSM or imperfect DSM for 1151 orthorectification, are influencing the accuracy and localisation of edge probabilities and consequently also the accuracy of adjusted BP. Note de contenu : bibliographie Numéro de notice : 19792 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère Note de thèse : PhD Dissertation : Photogrammetry : Stuttgart : 2016 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85016 Documents numériques
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Fusion of Hyperspectral Images and Digital Surface Models for Urban Object ExtractionAdobe Acrobat PDF Polygonal clustering analysis using multilevel graph-partition / Wanyi Wang in Transactions in GIS, vol 19 n° 5 (October 2015)
[article]
Titre : Polygonal clustering analysis using multilevel graph-partition Type de document : Article/Communication Auteurs : Wanyi Wang, Auteur ; Shihong Du, Auteur ; Zhou Guo, Auteur ; Liqun Luo, Auteur Année de publication : 2015 Article en page(s) : pp 716 – 736 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse comparative
[Termes IGN] analyse de groupement
[Termes IGN] connexité (graphes)
[Termes IGN] distance
[Termes IGN] données spatiotemporelles
[Termes IGN] figure géométrique
[Termes IGN] groupe
[Termes IGN] partition des données
[Termes IGN] polygone
[Termes IGN] similitudeRésumé : (auteur) Existing methods of spatial data clustering have focused on point data, whose similarity can be easily defined. Due to the complex shapes and alignments of polygons, the similarity between non-overlapping polygons is important to cluster polygons. This study attempts to present an efficient method to discover clustering patterns of polygons by incorporating spatial cognition principles and multilevel graph partition. Based on spatial cognition on spatial similarity of polygons, four new similarity criteria (i.e. the distance, connectivity, size and shape) are developed to measure the similarity between polygons, and used to visually distinguish those polygons belonging to the same clusters from those to different clusters. The clustering method with multilevel graph-partition first coarsens the graph of polygons at multiple levels, using the four defined similarities to find clusters with maximum similarity among polygons in the same clusters, then refines the obtained clusters by keeping minimum similarity between different clusters. The presented method is a general algorithm for discovering clustering patterns of polygons and can satisfy various demands by changing the weights of distance, connectivity, size and shape in spatial similarity. The presented method is tested by clustering residential areas and buildings, and the results demonstrate its usefulness and universality. Numéro de notice : A2015-684 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12124 En ligne : http://dx.doi.org/10.1111/tgis.12124 Format de la ressource électronique : Url artticle Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78325
in Transactions in GIS > vol 19 n° 5 (October 2015) . - pp 716 – 736[article]Semi-automated building footprint extraction from orthophotos / Rheannon Brooks in Geomatica, vol 69 n° 2 (June 2015)
[article]
Titre : Semi-automated building footprint extraction from orthophotos Type de document : Article/Communication Auteurs : Rheannon Brooks, Auteur ; Trisalyn Nelson, Auteur ; Krista Amolins, Auteur ; Brent Hall, Auteur Année de publication : 2015 Article en page(s) : pp 231 - 244 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] empreinte
[Termes IGN] extraction semi-automatique
[Termes IGN] orthoimage
[Termes IGN] photogrammétrie aérienne
[Termes IGN] polygone
[Termes IGN] segmentation d'imageRésumé : (auteur) Ici, nous décrivons et mettons en application une méthode semi-automatisée basée sur les objets pour l'extraction des polygones d'empreintes d’édifices vectorielles à partir de photographies aériennes (orthophotos) en milieu urbain. L'approche combine l'utilisation d'orthophotos à haute résolution et d'un logiciel de segmentation des images. On la compare à des méthodes qui utilisent la technologie LiDAR comme source d'entrée de données. Les données LiDAR offrent les meilleurs résultats avec moins de traitement, mais ne sont pas grandement utilisées par les municipalités en raison du coût qu'elles engendrent. Les résultats de la segmentation semi-automatisée des orthophotos ont démontré une grande exactitude entre les segments d’édifices extraits et les empreintes d’édifices, exactitude comparable aux résultats atteints en utilisant les données de la technologie LiDAR. Nous recommandons les images recueillies pendant les mois d’été avec une résolution de 10 X 10 cm. Lorsque les budgets d'acquisition sont limités, la meilleure stratégie est d'avoir recours à une combinaison de données SIG auxiliaires sur les routes et de l'approche de segmentation semi-automatisée basée sur les objets pour l'extraction des éléments de la couverture terrestre et la quantification des changements. Numéro de notice : A2015-395 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.5623/cig2015-206 En ligne : https://doi.org/10.5623/cig2015-206 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76873
in Geomatica > vol 69 n° 2 (June 2015) . - pp 231 - 244[article]Quantitative morphometric analysis of lakes using GIS: rectangularity R, ellipticity E, orientation O, and the rectangularity vs. ellipticity index, REi / Umberto Lombardo in Cartography and Geographic Information Science, vol 41 n° 4 (September 2014)
[article]
Titre : Quantitative morphometric analysis of lakes using GIS: rectangularity R, ellipticity E, orientation O, and the rectangularity vs. ellipticity index, REi Type de document : Article/Communication Auteurs : Umberto Lombardo, Auteur Année de publication : 2014 Article en page(s) : pp 340 - 347 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] Bolivie
[Termes IGN] ellipticité (géométrie)
[Termes IGN] géomorphométrie
[Termes IGN] lac
[Termes IGN] orientation
[Termes IGN] rectangleRésumé : (auteur) Quantitative measures of polygon shapes and orientation are important elements of geospatial analysis. These kinds of measures are particularly valuable in the case of lakes, where shape and orientation patterns can help identifying the geomorphological agents behind lake formation and evolution. However, the lack of built-in tools in commercial geographic information system (GIS) software packages designed for this kind of analysis has meant that many researchers often must rely on tools and workarounds that are not always accurate. Here, an easy-to-use method to measure rectangularity R, ellipticity E, and orientation O is developed. In addition, a new rectangularity vs. ellipticity index, REi, is defined. Following a step-by-step process, it is shown how these measures and index can be easily calculated using a combination of GIS built-in functions. The identification of shapes and estimation of orientations performed by this method is applied to the case study of the geometric and oriented lakes of the Llanos de Moxos, in the Bolivian Amazon, where shape and orientation have been the two most important elements studied to infer possible formation mechanisms. It is shown that, thanks to these new indexes, shape and orientation patterns are unveiled, which would have been hard to identify otherwise. Numéro de notice : A2014-429 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/15230406.2014.919540 En ligne : https://doi.org/10.1080/15230406.2014.919540 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=73966
in Cartography and Geographic Information Science > vol 41 n° 4 (September 2014) . - pp 340 - 347[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-2014041 RAB Revue Centre de documentation En réserve L003 Disponible A polygon-based clustering and analysis framework for mining spatial datasets / Sujing Wang in Geoinformatica, vol 18 n° 3 (July 2014)
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Titre : A polygon-based clustering and analysis framework for mining spatial datasets Type de document : Article/Communication Auteurs : Sujing Wang, Auteur ; Christoph F. Eick, Auteur Année de publication : 2014 Article en page(s) : pp 569 - 594 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] exploration de données géographiques
[Termes IGN] polygone
[Termes IGN] regroupement de donnéesRésumé : (Auteur) Polygons provide natural representations for many types of geospatial objects, such as countries, buildings, and pollution hotspots. Thus, polygon-based data mining techniques are particularly useful for mining geospatial datasets. In this paper, we propose a polygon-based clustering and analysis framework for mining multiple geospatial datasets that have inherently hidden relations. In this framework, polygons are first generated from multiple geospatial point datasets by using a density-based contouring algorithm called DCONTOUR. Next, a density-based clustering algorithm called Poly-SNN with novel dissimilarity functions is employed to cluster polygons to create meta-clusters of polygons. Finally, post-processing analysis techniques are proposed to extract interesting patterns and user-guided summarized knowledge from meta-clusters. These techniques employ plug-in reward functions that capture a domain expert's notion of interestingness to guide the extraction of knowledge from meta-clusters. The effectiveness of our framework is tested in a real-world case study involving ozone pollution events in Texas. The experimental results show that our framework can reveal interesting relationships between different ozone hotspots represented by polygons; it can also identify interesting hidden relations between ozone hotspots and several meteorological variables, such as outdoor temperature, solar radiation, and wind speed. Numéro de notice : A2014-501 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-013-0190-2 Date de publication en ligne : 30/08/2013 En ligne : https://doi.org/10.1007/s10707-013-0190-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74093
in Geoinformatica > vol 18 n° 3 (July 2014) . - pp 569 - 594[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2014031 RAB Revue Centre de documentation En réserve L003 Disponible Conflation optimized by least squares to maintain geographic shapes / Guillaume Touya in ISPRS International journal of geo-information, vol 2 n° 3 (September 2013)PermalinkImproving representation of land-use maps derived from object-oriented image classification / Wenxiu Gao in Transactions in GIS, vol 17 n° 3 (June 2013)PermalinkPermalinkA symmetry detector for map generalization and urban-space analysis / Jan‐Henrik Haunert in ISPRS Journal of photogrammetry and remote sensing, vol 74 (Novembrer 2012)PermalinkDetecting geometric conflicts for generalisation of polygonal maps / Wenxiu Gao in Cartographic journal (the), vol 49 n° 1 (February 2012)PermalinkMeasuring historical coastal change using GIS and the change polygon approach / M. Smith in Transactions in GIS, vol 16 n° 1 (February 2012)PermalinkPermalinkAmélioration d'une base de données d'empreintes de bâtiments pour la reconstruction 3D : une approche par découpe et fusion / Bruno Vallet in Revue Française de Photogrammétrie et de Télédétection, n° 195 (Novembre 2011)PermalinkBuilding footprint database improvement for 3D reconstruction: A split and merge approach and its evaluation / Bruno Vallet in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 5 (September - October 2011)PermalinkCity model enrichment / P. Smart ; J. Quinn ; C. Jones in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 2 (March - April 2011)Permalink