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Satellite images analysis for shadow detection and building height estimation / Gregoris Liasis in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)
[article]
Titre : Satellite images analysis for shadow detection and building height estimation Type de document : Article/Communication Auteurs : Gregoris Liasis, Auteur ; Stavros Stavrou, Auteur Année de publication : 2016 Article en page(s) : pp 437 - 450 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] contour
[Termes IGN] délimitation
[Termes IGN] détection d'ombre
[Termes IGN] filtre spectral
[Termes IGN] hauteur du bâti
[Termes IGN] image satellite
[Termes IGN] intensité lumineuse
[Termes IGN] ombre
[Termes IGN] scène urbaine
[Termes IGN] valeur radiométriqueRésumé : (Auteur) Satellite images can provide valuable information about the presented urban landscape scenes to remote sensing and telecommunication applications. Obtaining information from satellite images is difficult since all the objects and their surroundings are presented with feature complexity. The shadows cast by buildings in urban scenes can be processed and used for estimating building heights. Thus, a robust and accurate building shadow detection process is important. Region-based active contour models can be used for satellite image segmentation. However, spectral heterogeneity that usually exists in satellite images and the feature similarity representing the shadow and several non-shadow regions makes building shadow detection challenging. In this work, a new automated method for delineating building shadows is proposed. Initially, spectral and spatial features of the satellite image are utilized for designing a custom filter to enhance shadows and reduce intensity heterogeneity. An effective iterative procedure using intensity differences is developed for tuning and subsequently selecting the most appropriate filter settings, able to highlight the building shadows. The response of the filter is then used for automatically estimating the radiometric property of the shadows. The customized filter and the radiometric feature are utilized to form an optimized active contour model where the contours are biased to delineate shadow regions. Post-processing morphological operations are also developed and applied for removing misleading artefacts. Finally, building heights are approximated using shadow length and the predefined or estimated solar elevation angle. Qualitative and quantitative measures are used for evaluating the performance of the proposed method for both shadow detection and building height estimation. Numéro de notice : A2016-792 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2016.07.006 En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2016.07.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82509
in ISPRS Journal of photogrammetry and remote sensing > vol 119 (September 2016) . - pp 437 - 450[article]An improved ANUDEM method combining topographic correction and DEM interpolation / Xianwei Zheng in Geocarto international, vol 31 n° 5 - 6 (May - June 2016)
[article]
Titre : An improved ANUDEM method combining topographic correction and DEM interpolation Type de document : Article/Communication Auteurs : Xianwei Zheng, Auteur ; H. Xiong, Auteur ; Jianya Gong, Auteur ; Linwei Yue, Auteur Année de publication : 2016 Article en page(s) : pp 492 - 505 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] contour
[Termes IGN] correction topographique
[Termes IGN] détail topographique
[Termes IGN] interpolation spatiale
[Termes IGN] modèle numérique de surface
[Termes IGN] reliefRésumé : (Auteur) Void filling and anomaly replacement in conjunction with auxiliary sources of data have been widely used to improve the quality of existing problematic high-resolution digital elevation models. However, the traditional interpolation methods used for this purpose have always failed to eliminate the discrepancies between different data-sets. In this paper, an improved ANUDEM method is presented for DEM interpolation, which incorporates the idea of topographic correction using high correlation of topological structure between contour lines (CLs) from multi-scale digital elevation models (DEM). Firstly, the terrain topological structure is extracted from the CLs of a low-resolution DEM. The topographic surface correction is then undertaken based on the extracted structure, which recovers the topographic information of the sharp depressions and eminences to fit the high-resolution representation. Finally, the breaklines of the terrain surface are distilled and integrated into the denser DEM generation. The experiments undertaken confirmed the superiority of the proposed method over the other DEM interpolation methods. It is shown that the proposed method can provide results with a higher accuracy, as well as a better visual quality. Numéro de notice : A2016-168 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2015.1059899 Date de publication en ligne : 11/07/2015 En ligne : http://www.tandfonline.com/doi/full/10.1080/10106049.2015.1059899 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80507
in Geocarto international > vol 31 n° 5 - 6 (May - June 2016) . - pp 492 - 505[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2016031 RAB Revue Centre de documentation En réserve L003 Disponible Evaluating tree detection and segmentation routines on very high resolution UAV LiDAR data / Luke Wallace in IEEE Transactions on geoscience and remote sensing, vol 52 n° 12 (December 2014)
[article]
Titre : Evaluating tree detection and segmentation routines on very high resolution UAV LiDAR data Type de document : Article/Communication Auteurs : Luke Wallace, Auteur ; Arko Lucieer, Auteur ; Christopher S. Watson, Auteur Année de publication : 2014 Article en page(s) : pp 7619 - 7628 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] arbre (flore)
[Termes IGN] canopée
[Termes IGN] contour
[Termes IGN] détection de cible
[Termes IGN] données lidar
[Termes IGN] drone
[Termes IGN] Eucalyptus globulus
[Termes IGN] hauteur des arbres
[Termes IGN] image à très haute résolution
[Termes IGN] implémentation (informatique)
[Termes IGN] prise de vue aérienne
[Termes IGN] semis de pointsRésumé : (Auteur) Light detection and Ranging (LiDAR) is becoming an increasingly used tool to support decision-making processes within forest operations. Area-based methods that derive information on the condition of a forest based on the distribution of points within the canopy have been proven to produce reliable and consistent results. Individual tree-based methods, however, are not yet used operationally in the industry. This is due to problems in detecting and delineating individual trees under varying forest conditions resulting in an underestimation of the stem count and biases toward larger trees. The aim of this paper is to use high-resolution LiDAR data captured from a small multirotor unmanned aerial vehicle platform to determine the influence of the detection algorithm and point density on the accuracy of tree detection and delineation. The study was conducted in a four-year-old Eucalyptus globulus stand representing an important stage of growth for forest management decision-making process. Five different tree detection routines were implemented, which delineate trees directly from the point cloud, voxel space, and the canopy height model (CHM). The results suggest that both algorithm and point density are important considerations in the accuracy of the detection and delineation of individual trees. The best performing method that utilized both the CHM and the original point cloud was able to correctly detect 98% of the trees in the study area. Increases in point density (from 5 to 50 points/m2) lead to significant improvements (of up to 8%) in the rate of omission for algorithms that made use of the high density of the data. Numéro de notice : A2014-640 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2014.2315649 En ligne : https://doi.org/10.1109/TGRS.2014.2315649 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75077
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 12 (December 2014) . - pp 7619 - 7628[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014121 RAB Revue Centre de documentation En réserve L003 Disponible Airborne LiDAR and terrestrial laser scanning derived vegetation obstruction factors for visibility models / Jayson Murgoitio in Transactions in GIS, vol 18 n° 1 (February 2014)
[article]
Titre : Airborne LiDAR and terrestrial laser scanning derived vegetation obstruction factors for visibility models Type de document : Article/Communication Auteurs : Jayson Murgoitio, Auteur ; Rupesh Shrestha, Auteur ; Nancy Glenn, Auteur ; Lucas Spaete, Auteur Année de publication : 2014 Article en page(s) : pp 125 - 146 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] arbre (flore)
[Termes IGN] base de données dérivée
[Termes IGN] contour
[Termes IGN] corrélation
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] écosystème forestier
[Termes IGN] intégration de données
[Termes IGN] Pinus contorta
[Termes IGN] régression
[Termes IGN] télémétrie laser aéroporté
[Termes IGN] télémétrie laser terrestre
[Termes IGN] visibilitéRésumé : (Auteur) Research presented here explores the feasibility of leveraging vegetation data derived from airborne light detection and ranging (LiDAR) and terrestrial laser scanning (TLS) for visibility modeling. Using LiDAR and TLS datasets of a lodgepole pine (Pinus contorta) dominant ecosystem, tree canopy and trunk obstructions were isolated relevant to a discrete visibility beam in a short-range line-of-sight model. Cumulative obstruction factors from vegetation were compared with reference visibility values from digital photographs along sightline paths. LiDAR-derived tree factors were augmented with single-scan TLS data for obstruction prediction. Good correlation between datasets was found up to 10 m from the terrestrial scanner, but fine scale visibility modeling was problematic at longer distances. Analysis of correlation and regression results reveal the influence of obstruction shadowing inherent to discrete LiDAR and TLS, potentially limiting the feasibility of modeling visibility over large areas with similar technology. However, the results support the potential for TLS-derived subcanopy metrics for augmenting large amounts of aerial LiDAR data to significantly improve models of forest structure. Subtle LiDAR processing improvements, including more accurate tree delineation through higher point density aerial data, combined with better vegetation quantification processes for TLS data, will advance the feasibility and accuracy of data integration. Numéro de notice : A2014-069 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12022 Date de publication en ligne : 17/05/2013 En ligne : https://doi.org/10.1111/tgis.12022 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32974
in Transactions in GIS > vol 18 n° 1 (February 2014) . - pp 125 - 146[article]Multi-level representation of terrain features on a contour map / Eric Guilbert in Geoinformatica, vol 17 n° 2 (April 2013)
[article]
Titre : Multi-level representation of terrain features on a contour map Type de document : Article/Communication Auteurs : Eric Guilbert, Auteur Année de publication : 2013 Article en page(s) : pp 301 - 324 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] adjacence
[Termes IGN] arbre (mathématique)
[Termes IGN] carte isoplèthe
[Termes IGN] contour
[Termes IGN] description multiniveau
[Termes IGN] détail topographique
[Termes IGN] généralisation automatique de données
[Termes IGN] représentation multipleRésumé : (Auteur) Contour lines are important for quantitatively displaying relief and identifying morphometric features on a map. Contour trees are often used to represent spatial relationships between contours and assist the user in analysing the terrain. However, automatic analysis from the contour tree is still limited as features identified on a map by sets of contours are not only characterised by local relationships between contours but also by relationships with other features at different levels of representation. In this paper, a new method based on adjacency and inclusion relationships between regions defined by sets of contours is presented. The method extracts terrain features and stores them in a feature tree providing a description of the landscape at multiple levels of detail. The method is applied to terrain analysis and generalisation of a contour map by selecting the most relevant features according to the purpose of the map. Experimental results are presented and discussed. Numéro de notice : A2013-161 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-012-0153-z Date de publication en ligne : 11/04/2012 En ligne : https://doi.org/10.1007/s10707-012-0153-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32299
in Geoinformatica > vol 17 n° 2 (April 2013) . - pp 301 - 324[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2013021 RAB Revue Centre de documentation En réserve L003 Disponible Automated planimetric quality control in high accuracy airborne laser scanning surveys / M. George Vosselman in ISPRS Journal of photogrammetry and remote sensing, vol 74 (Novembrer 2012)PermalinkEdge-guided multiscale segmentation of satellite multispectral imagery / J. Chen in IEEE Transactions on geoscience and remote sensing, vol 50 n° 11 Tome 1 (November 2012)PermalinkVerification of 2D building outlines using oblique airborne images / A. Nyaruhuma in ISPRS Journal of photogrammetry and remote sensing, vol 71 (July 2012)PermalinkAn edge-oriented approach to thematic map error assessment / S. Sweeney in Geocarto international, vol 27 n° 1 (February 2012)PermalinkCARTOLIS : Vers un outil géomatique pour identifier et caractériser les segments de lisières forestières / Audrey Alignier in Revue internationale de géomatique, vol 21 n° 4 (décembre 2011 – février 2012)PermalinkUsing snakes for the registration of topographic road database objects to ALS features / J. Göpfert in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 6 (November 2011)PermalinkUsing horizontal and vertical building structure to constrain indirect sensor orientation / Markus Gerke in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 3 (May - June 2011)Permalink3D building model reconstruction from multi-view aerial imagery and Lidar data / Liang Cheng in Photogrammetric Engineering & Remote Sensing, PERS, vol 77 n° 2 (February 2011)PermalinkPermalinkObtaining high fidelity triangular Regular Network from only DEM points / T. Gökgöz in Cartographic journal (the), vol 47 n° 2 (May 2010)Permalink