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Detecting and measuring individual trees using an airborne laser scanner / A. Persson in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 9 (September 2002)
[article]
Titre : Detecting and measuring individual trees using an airborne laser scanner Type de document : Article/Communication Auteurs : A. Persson, Auteur ; Johan Holmgren, Auteur Année de publication : 2002 Article en page(s) : pp 925 - 932 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] arbre (flore)
[Termes IGN] contour
[Termes IGN] données lidar
[Termes IGN] erreur moyenne quadratique
[Termes IGN] forêt
[Termes IGN] houppier
[Termes IGN] télémétrie laser aéroporté
[Termes IGN] troncRésumé : (Auteur) High-resolution airborne laser scanner data offer the possibility to detect and measure individual trees. In this study, an algorithm which estimated position, height, and crown diameter of individual trees was validated with field measurements. Because all the trees in this study were measured on the ground with high accuracy, their positions could be linked with laser measurements, making validation on an individual tree basis possible. In total, 71 percent of the trees were correctly detected using laser scanner data. Because a large portion of the undetected trees had a small stem diameter, 91 percent of the total stem volume was detected. Height and crown diameter of detected trees could be estimated with a root-mean-square error (RMSE) of 0,63 m and 0,61 m, respectively. Stem diameter was estimated, using laser measured tree height and crown diameter, with an RMSE of 3,8 cm. Different laser beam diameters (0,26 to 3,68 m) were also tested, the smallest beam size showing a better detection rate in dense forest. However, estimates of tree height and crown diameter were not affected much by different beam size. Copyright ASPRS Numéro de notice : A2002-323 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : sans En ligne : https://www.asprs.org/wp-content/uploads/pers/2002journal/september/2002_sep_925 [...] Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22234
in Photogrammetric Engineering & Remote Sensing, PERS > vol 68 n° 9 (September 2002) . - pp 925 - 932[article]Application of snakes and dynamic programming optimisation technique in modeling of buildings in informal settlement areas / H. Ruther in ISPRS Journal of photogrammetry and remote sensing, vol 56 n° 4 (July - August 2002)
[article]
Titre : Application of snakes and dynamic programming optimisation technique in modeling of buildings in informal settlement areas Type de document : Article/Communication Auteurs : H. Ruther, Auteur ; H.M. Martine, Auteur ; E.G. Mtalo, Auteur Année de publication : 2002 Article en page(s) : pp 269 - 282 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] contour
[Termes IGN] détection du bâti
[Termes IGN] modèle mathématique
[Termes IGN] modèle numérique de surface
[Termes IGN] orthophotographie
[Termes IGN] photographie aérienne
[Termes IGN] processeurRésumé : (Auteur) This paper presents a novel approach to semiautomatic building extraction in informal settlement areas from aerial photographs. The proposed approach uses a strategy of delineating buildings by optimising their approximate building contour position. Approximate building contours are derived automatically by locating elevation blobs in digital surface models. Building extraction is then effected by means of the snakes algorithm and the dynamic programming optimisation technique. With dynamic programming, the building contour optimisation problem is realized through a discrete multistage process and solved by the "timedelayed" algorithm, as developed in this work. The proposed building extraction approach is a semiautomatic process, with usercontrolled operations linking fully automated subprocesses. Inputs into the proposed building extraction system are orthoimages and digital surface models, the latter being generated through image matching techniques. Buildings are modeled as "lumps" or elevation blobs in digital surface models, which are derived by altimetric thresholding of digital surface models. Initial windows for building extraction are provided by projecting the elevation blobs centre points onto an orthoimage. In the next step, approximate building contours are extracted from the orthoimage by region growing constrained by edges. Approximate building contours thus derived are inputs into the dynamic programming optimisation process in which final building contours are established. The proposed system is tested on two study areas: Marconi Beam in Cape Town, South Africa, and Manzese in Dar es Salaam, Tanzania. Sixty percent of buildings in the study areas have been extracted and verified and it is concluded that the proposed approach contributes meaningfully to the extraction of buildings in moderately complex and crowded informal settlement areas. Copyright ISPRS Numéro de notice : A2002-169 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/S0924-2716(02)00062-X En ligne : https://doi.org/10.1016/S0924-2716(02)00062-X Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22084
in ISPRS Journal of photogrammetry and remote sensing > vol 56 n° 4 (July - August 2002) . - pp 269 - 282[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-02021 SL Revue Centre de documentation Revues en salle Disponible Preserving cartographic quality in DTM interpolation from contour lines / Gil Rito-Gonçalves in ISPRS Journal of photogrammetry and remote sensing, vol 56 n° 3 (April - June 2002)
[article]
Titre : Preserving cartographic quality in DTM interpolation from contour lines Type de document : Article/Communication Auteurs : Gil Rito-Gonçalves , Auteur ; Patrick Julien , Auteur ; S. Razanioff, Auteur ; Bernard Cervelle, Auteur Année de publication : 2002 Article en page(s) : pp 210 - 220 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] contour
[Termes IGN] courbe de niveau
[Termes IGN] diagramme de Voronoï
[Termes IGN] interpolation
[Termes IGN] modèle numérique de terrain
[Termes IGN] orographie
[Termes IGN] qualité cartographique
[Termes IGN] triangulation de DelaunayRésumé : (Auteur) Fitting an elastic grid to contour lines (CLs) produces a surface with tighter intermediate contours than the initial ones. This leads to intermediate contours that do not match the initial ones. In this paper, we propose a method for correcting this defect, by fitting the elastic grid to supplementary constraint lines that correspond approximately to the terrain morphologic lines (ridges and drainages). We extract these lines from a Delaunay triangulation consistent with the contour lines. We propose a coherent weighting system for the constraints imposed on the elastic grid. Finally, we show that a digital terrain model (DTM) artefact of the type mentioned above can be detected by a simple criterion such as the contour length. Copyright ISPRS Numéro de notice : A2002-095 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/S0924-2716(02)00044-8 En ligne : https://doi.org/10.1016/S0924-2716(02)00044-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22010
in ISPRS Journal of photogrammetry and remote sensing > vol 56 n° 3 (April - June 2002) . - pp 210 - 220[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-02011 SL Revue Centre de documentation Revues en salle Disponible Characterization of complex bends / Xavier Barillot (2002)
contenu dans Proceedings of the GIS Research UK, 10th Annual Conference, GISRUK 2002, 3rd - 5th April, University of Sheffield / Steve Wise (2002)
Titre : Characterization of complex bends Type de document : Article/Communication Auteurs : Xavier Barillot , Auteur Editeur : Saint-Mandé : Institut Géographique National - IGN (2008-2011) Année de publication : 2002 Conférence : GISRUK 2002, 10th GIS research UK annual conference 03/04/2002 05/04/2002 Sheffield Royaume-Uni Importance : pp 179 - 181 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] caractérisation
[Termes IGN] contour
[Termes IGN] objet géographique linéaire
[Termes IGN] polyligne
[Termes IGN] segmentation
[Termes IGN] virage
[Vedettes matières IGN] GénéralisationRésumé : (auteur) This communication deals with the characterization of linear features in a geographical database. The context is map generalization: many works have shown the necessity to characterize objects before generalizing — see for instance [McMaster 1983], [Buttenfield 1984], [Runs & Lagrange 1995: 76-79], [Plazanet 1996]. In this context, we also need to evaluate the result of the transformation: the simplified object must be similar to the original one, not only in location, but also in global and local shape. The aim of this paper is to give a method of automatic characterization of the local shapes of linear objects, i.e. a characterization of the bends. Numéro de notice : C2002-022 Affiliation des auteurs : COGIT (1988-2011) Thématique : GEOMATIQUE/INFORMATIQUE Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82961 Extracting 3D edgels hypotheses from multiple calibrated images : a step towards the reconstruction of curved and straight object boundary lines / Franck Jung (2002)
contenu dans Proceedings of the ISPRS commission 3 symposium, Photogrammetric computer vision, september 9 - 13, 2002, Graz Austria, Part B. Papers accepted on the basis of abstracts / R. Kalliany (2002)
Titre : Extracting 3D edgels hypotheses from multiple calibrated images : a step towards the reconstruction of curved and straight object boundary lines Type de document : Article/Communication Auteurs : Franck Jung , Auteur ; Vincent Tollu, Auteur ; Nicolas Paparoditis , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2002 Collection : International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, ISSN 1682-1750 num. 34-3B Conférence : PCV 2002, ISPRS commission 3 symposium, Photogrammetric computer vision 09/09/2002 13/09/2002 Graz Autriche OA ISPRS Archives Importance : pp 100 - 104 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] contour
[Termes IGN] image aérienne
[Termes IGN] reconstruction d'objet
[Termes IGN] Triangulated Irregular NetworkRésumé : (auteur) This paper describes a novel technique to extract 3D elementary linear elements from multiple views, often called edgels, that are 3D points with tangent direction. Techniques based on stereopair feature, edgel or contour, matching have been intensively developed in the 80s. The relatively poor quality of images used at the time and the ill-posed stereo context contributed to focus the research around segment matching, which provided fairly good results on objects with rectilinear boundaries. Here, we take advantage of the multiplication and of the high quality of images provided by a digital frame camera to revisit this feature matching technique and to enhance the accuracy, the detection and the robustness of a 3D elementary edgel feature estimator. 3D edgels introduce the lowest implicit modelisation as possible, thus allowing the characterisation and reconstruction of curved and straight linear structures which are widespread in our manmade world. The 3D points with tangent directions generated by our estimator can be directly injected in a surface reconstruction framework based on tensor voting (Tang and Medioni, 1998). In a more practical and photogrammetric context, e.g. HR aerial images of urban landscapes, these low-level features can be used to build 3D lines that can be injected as constraint lines in addition to other features, such as 3D points and 3D segments, in a triangulation process (Paparoditis et al., 2001) to improve the surface reconstruction of manmade objects (buildings, pavements, roads, etc.). These features can also be used to construct higher level features such as planar facets in aerial images of urban areas for building reconstruction. Numéro de notice : C2002-025 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE Nature : Communication nature-HAL : Poster-avec-CL DOI : sans En ligne : http://www.isprs.org/proceedings/XXXIV/part3/papers/paper144.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86135 Documents numériques
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Extracting 3D edgels hypotheses - pdf éditeurAdobe Acrobat PDF Réalisation d'un système d'information géographique dédié à l'étude des déformations de surface sur la ville de Paris / J.L. Kouame (2002)PermalinkModifications of Tanaka's illuminated contour method / Patrick Kennelly in Cartography and Geographic Information Science, vol 28 n° 2 (April 2001)PermalinkAn integrated technique for automated generalization of contour maps / Z. Li in Cartographic journal (the), vol 37 n° 1 (June 2000)PermalinkSemi-automatic contour line generation: advanced manuel editing tools for proper results / Alain Dupéret in GIM international, vol 14 n° 3 (March 2000)PermalinkPermalinkPermalinkReconstruction de courbes et de surfaces 3D en stéréo-acquisition / David Roussel (1999)PermalinkDetermination of terrain models in wooded areas with airborne laser scanner data / Karl Kraus in ISPRS Journal of photogrammetry and remote sensing, vol 53 n° 4 (August - september 1998)PermalinkPermalinkGenauigkeit geometrischer Größen aus Vektordaten / F. Bethge (1997)Permalink