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contourSynonyme(s)Ligne de contour |
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[article]
Titre : Revealing images Type de document : Article/Communication Auteurs : Anonyme, Auteur Année de publication : 2005 Article en page(s) : pp 49 - 51 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] classification dirigée
[Termes IGN] contour
[Termes IGN] densité des points
[Termes IGN] modèle numérique de surface
[Termes IGN] modélisation 3D
[Termes IGN] réalité virtuelle
[Termes IGN] Suède
[Termes IGN] télémétrie laser aéroporté
[Termes IGN] vitesse de traitementRésumé : (Editeur) GEO:connexion takes the wraps off advanced techniques evolved at Sweden's Defence Research Agency for the rapid 3D modelling of the real-world environments. Numéro de notice : A2005-033 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27171
in GEO:connexion > vol 4 n° 1 (january 2005) . - pp 49 - 51[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 062-05011 RAB Revue Centre de documentation En réserve L003 Disponible L'extraction du bâti à partir d'images satellitaires THRS / Serge Lhomme in Revue internationale de géomatique, vol 14 n° 3 - 4 (septembre 2004 – février 2005)
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[article]
Titre : L'extraction du bâti à partir d'images satellitaires THRS Type de document : Article/Communication Auteurs : Serge Lhomme, Auteur ; Christiane Weber, Auteur ; Dong-Chen He, Auteur Année de publication : 2004 Article en page(s) : pp 465 - 484 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] analyse de variance
[Termes IGN] contour
[Termes IGN] détection du bâti
[Termes IGN] extraction automatique
[Termes IGN] image à résolution métrique
[Termes IGN] image Ikonos
[Termes IGN] qualité géométrique (image)
[Termes IGN] qualité radiométrique (image)Résumé : (Auteur) La disponibilité récente des images satellitales à très haute résolution spatiale offre un potentiel cartographique théorique pour les échelles allant du 1:50 000 au 1:100 000e. Deux principales conditions sont cependant requises pour passer de ce potentiel à une cartographie automatique opérationnelle. La première est liée aux images qui en plus de la résolution spatiale doivent répondre à des critères de qualité radiométrique et géométrique. La seconde est liée aux méthodes de traitements qui doivent être adaptées à ces nouvelles images. Cet article se focalise sur les méthodes d'extraction automatique du bâti. Une revue des méthodes récemment développées montre que le principal problème est la délimitation précise des contours des bâtiments. Face à ce constat nous considérons une hypothèse de discrimination des bâtiments basée sur le rapport de variance entre le bâtiment et son contour. Numéro de notice : A2004-593 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.3166/rig.14.465-484 En ligne : https://doi.org/10.3166/rig.14.465-484 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27109
in Revue internationale de géomatique > vol 14 n° 3 - 4 (septembre 2004 – février 2005) . - pp 465 - 484[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 047-04031 RAB Revue Centre de documentation En réserve L003 Disponible Using Landsat 7 TM data acquired days after a flood event to delineate the maximum flood extent on a coastal floodplain / Y. Wang in International Journal of Remote Sensing IJRS, vol 25 n° 5 (March 2004)
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[article]
Titre : Using Landsat 7 TM data acquired days after a flood event to delineate the maximum flood extent on a coastal floodplain Type de document : Article/Communication Auteurs : Y. Wang, Auteur Année de publication : 2004 Article en page(s) : pp 959 - 974 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse diachronique
[Termes IGN] contour
[Termes IGN] détection de contours
[Termes IGN] image Landsat-TM
[Termes IGN] inondation
[Termes IGN] zone inondableRésumé : (Auteur) In response to Hurricane Floyd, the Tar River crested at a record height of 4.30m above the flood stage at the river gauge station of Greenville (North Carolina, USA) on 21 September 1999. This resulted in a massive flooding in the area. To delineate the maximum flood extent, an area of 238.4 km2 along the Tar/Pamlico River, North Carolina, and within the overlapped area of Landsat 7 Thematic Mapper (TM) path 14/row 35 and path 15/row 35 scenes was studied. Three TM datasets of 28 July 1999 (path 15/row 35), 23 September 1999 (path 14/row 35) and 30 September 1999 (path 15/row 35) were analysed as preflood data, near peak data, and nine days after the peak data, respectively. The 23 and 30 September flood extent maps were derived by change detection and then verified by 85 nonflooded and flooded sites within the study area. The overall accuracies at the sites were between 82.599.3% on both inundation extent maps. Although the recorded river surface level fell 2.62 m from 23 to 30 September at the river gauge station of Greenville, comparison of the two flood extent maps on a pixel-by-pixel basis showed an agreement of 90.7% in terms of regular river channels and waterbodies, flooded areas and nonflooded areas. The 30 September map captured over 90% of the flood extent as identified on the 23 September map. These results suggest that it is possible to use remotely sensed data acquired days after a river's crest to capture most of the maximum extent of a flood occurring on a coastal floodplain. and should somewhat reduce the requirement to have concurrently remotely sensed data in mapping a flood extent on a coastal floodplain. Numéro de notice : A2004-078 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000150022 En ligne : https://doi.org/10.1080/0143116031000150022 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26606
in International Journal of Remote Sensing IJRS > vol 25 n° 5 (March 2004) . - pp 959 - 974[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-04051 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Application of wavelet transform for extracting edges of paddy fields from remotely sensed images / T. Ishida in International Journal of Remote Sensing IJRS, vol 25 n° 2 (January 2004)
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[article]
Titre : Application of wavelet transform for extracting edges of paddy fields from remotely sensed images Type de document : Article/Communication Auteurs : T. Ishida, Auteur ; S. Itagaki, Auteur ; Y. Sasaki, Auteur ; H. Ando, Auteur Année de publication : 2004 Article en page(s) : pp 347 - 357 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] contour
[Termes IGN] détection de contours
[Termes IGN] filtrage numérique d'image
[Termes IGN] image SPOT
[Termes IGN] polygone
[Termes IGN] transformation en ondelettesRésumé : (Auteur) For geographical information systems (GIS) to be useful in the management of Japanese paddy fields, it is vital to be able to prepare base maps that define sections of field. We attempted to prepare a base map by detecting the edges of submerged paddy fields from a SPOT image with the use of multiresolution wavelet transform. The raw image of SPOT band 3 was decomposed into a low frequency approximation image and a set of high frequency detailed images to five levels, and then reconstructed. The reconstructed image at the fifth level was obtained from all of the high frequency images except for the low frequency approximation image. The image reconstructed up to full scale was then applied to a zero-crossing scheme and three post-processings-line thinning, removal of isolated pixels, and connection of pixels with their neighbours in order to obtain clear edges. The spatial features of the image indicating the edges obtained by multi-resolution wavelet transform were compared quantitatively with those obtained by using a difference of Gaussian (DOG) filter. The multi-resolution wavelet transform was better than the DOG filter in that the base map obtained by the wavelet transform method represented a 'field block', which is typically composed of 10 holdings of paddy field, more precisely than with the DOG filter, and in that the number of open polygons on this map was smaller, indicating that the wavelet transform method is more suitable for producing the base map in GIS for the management of paddy fields. Numéro de notice : A2004-054 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000115120 En ligne : https://doi.org/10.1080/0143116031000115120 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26582
in International Journal of Remote Sensing IJRS > vol 25 n° 2 (January 2004) . - pp 347 - 357[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-04021 RAB Revue Centre de documentation En réserve L003 Exclu du prêt
Titre : Modellierung von Oberflächen mit Diskontinuitäten Titre original : [Modélisation des superficies avec des discontinuités] Type de document : Thèse/HDR Auteurs : Andrzej Borkowski, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2004 Collection : DGK - C Sous-collection : Dissertationen num. 575 Importance : 91 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-5014-3 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] contour
[Termes IGN] données laser
[Termes IGN] lasergrammétrie
[Termes IGN] lissage de données
[Termes IGN] modèle numérique de terrain
[Termes IGN] semis de points
[Termes IGN] vectorisationIndex. décimale : 35.20 Traitement d'image Résumé : (Auteur) The laser scanning provides very dense information about the surface to be modelled in the form of a irregularly distributed points cloud {x, y, z} c R3. Such dense information makes possible an efficient modelling of characteristic structures of the terrain surface like discontinuities, which are necessary for high-qualitative description of the surface. Simultaneously, the points not belonging to the modelled surface (for example: reflexes from buildings, trees etc.) stand a very important influence on the obtained data. During the modelling process, such data should be effectively filtered from the whole data set.
The laser scanning data can be efficiently elaborated by the use of deformable models of curves and surfaces. These models base on the physical principle of energy-minimizing and are presented as the solution of variational problem. The total energy consists both of internal and external energy. The external energy, depending on a context is generated by the data; in most cases it describes a deviation between the data and a model. The internal energy describes geometrical properties of curves and is characterized by elasticity and viscosity. Both terms are mutually weighted by the local control parameters a and 0. Varying the parameters makes it possible to stretch the curves to a geometrical shapes. The snake-approximation is used for a profiled modelling of surfaces. Due to that, a formulation of external energy was proposed making possible a robust modelling of profiles: during an iterative process, gross errors can be filtered, measuring errors can be smoothed and discontinuities can be preserved. Fitting the snakes-models to the data runs iteratively, however the control parameters depending on the data are being spread.
By generalizing the snakes, the model is introduced by sufficient smoothes, energy-charged pieces of a surface and furthermore described by flakes. The internal energy within the flakes model consists of a membrane and a thin-plate kernel which describes the inclination and curvature properties of the modelled terrain surface. The energy pieces will furthermore be weighted by the local control parameters a and fl. A minimizing of the total flakes energy leads again to the variational problem which had been differently solved. By formulate the Euler equations and their further diskretizing by finite differences, the flakes-model stands for regular data. The previous variational problem will also be solved by the use of so-called Ritz method. The improved flakes model was developed for regular data by using a linear base function. However, for the irregular data the flakes model was modified by the use of a Gaussian function. The modelling of the data by flakes runs iteratively. By using the flakes model for regular data it is possible to reject the gross errors, also to smooth the noise by simultaneous preserving the form of edges.
In many applications the information about spatial location of terrain edges is needed. To present such spatial location description of edges in a vector format based on irregular points cloud {x, y, z} obtained during laser scanning, it was proposed to describe a gross-errors-free data by surface functions and to average the edges as a intersection of two surfaces zi = fi(x, y) ; i = 1, 2. To this purpose, all the data should furthermore be ordered in separate pieces of the surface. This problem can be solved by using the standard methods of image processing. The projection {x(s), y(s)} of edges is found in the xy coordinate plane and the z-coordinates consist of fi (x(s), y(s)). To the intersection of two surfaces relates: f1 (x(s), y(s)) = f2 (x(s), y(s)) = 0. Based on this condition, two approaches of intersection curve identification were developed. The line-tracking algorithm relies on numerical integration of differential equations relative to the particular problem. For the numerical integration there is a starting point needed. Due to that, a seeking-approach was proposed. Opposite to the local algorithm it was presented a global approach using a snakes-method with a proper definition of external energy. Both algorithms make it possible a reliable, high-accurate identification of terrain edges basing on irregular points cloud.
The algorithms and approaches developed in this work have been tested on real data sets obtained by a laser scanning. Furthermore, a qualitative consideration of a modelling has been given. Finally, some hints for user according the steering and operating of the approaches have been presented.Numéro de notice : 13256 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54940 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 13256-01 35.20 Livre Centre de documentation Télédétection Disponible Automatic satellite image georeferencing using a contour-matching approach / Francisco Eugenio in IEEE Transactions on geoscience and remote sensing, vol 41 n° 12 (December 2003)
PermalinkRoad vectors update using SAR imagery: a snake-based method / L. Bentabet in IEEE Transactions on geoscience and remote sensing, vol 41 n° 8 (August 2003)
PermalinkThe representation of topographic information on maps: The depiction of relief / P. Collier in Cartographic journal (the), vol 40 n° 1 (June 2003)
PermalinkSpatial database updating using active contours for multispectral images: application with Landsat 7 / S. Jodouin in ISPRS Journal of photogrammetry and remote sensing, vol 57 n° 5-6 (April - May 2003)
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)
PermalinkRoof boundary extraction using multiple images / Ahmed F. Elaksher in Photogrammetric record, vol 18 n° 101 (March - May 2003)
PermalinkAutomatic matching and three-dimensional reconstruction of free-form linear features from stereo images / A.F. Habib in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 2 (February /2003)
PermalinkRobust reconstruction of building models from three-dimensional line segments / Jiann-Yeou Rau in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 2 (February /2003)
PermalinkPermalinkDEM generation method from contour lines based on the steepest slope segment chain and a monotone interpolation function / P.O. Adriansyah in ISPRS Journal of photogrammetry and remote sensing, vol 57 n° 1-2 (November - December 2002)
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