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STHist-C: a highly accurate cluster-based histogram for two and three dimensional geographic data points / Hai Thanh Mai in Geoinformatica, vol 17 n° 2 (April 2013)
[article]
Titre : STHist-C: a highly accurate cluster-based histogram for two and three dimensional geographic data points Type de document : Article/Communication Auteurs : Hai Thanh Mai, Auteur ; Jaeho Kim, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 325 - 352 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] base de données localisées
[Termes IGN] données localisées 2D
[Termes IGN] données localisées 3D
[Termes IGN] histogramme
[Termes IGN] regroupement de données
[Termes IGN] système d'information géographique
[Termes IGN] traitement de données localiséesRésumé : (Auteur) Histograms have been widely used for estimating selectivity in query optimization. In this paper, we propose a new histogram construction method for geographic data objects that are used in many real-world applications. The proposed method is based on analyses and utilization of clusters of objects that exist in a given data set, to build histograms with significantly enhanced accuracy. Our philosophy in allocating the histogram buckets is to allocate them to the subspaces that properly capture object clusters. Therefore, we first propose a procedure to find the centers of object clusters. Then, we propose an algorithm to construct the histogram buckets from these centers. The buckets are initialized from the clusters’ centers, then expanded to cover the clusters. Best expansion plans are chosen based on a notion of skewness gain. Results from extensive experiments using real-life data sets demonstrate that the proposed method can really improve the accuracy of the histograms further, when compared with the current state of the art histogram construction method for geographic data objects. Numéro de notice : A2013-162 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-012-0154-y Date de publication en ligne : 10/02/2012 En ligne : https://doi.org/10.1007/s10707-012-0154-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32300
in Geoinformatica > vol 17 n° 2 (April 2013) . - pp 325 - 352[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2013021 RAB Revue Centre de documentation En réserve L003 Disponible An improved simple morphological filter for the terrain classification of airborne LIDAR data / Thomas J. Pingel in ISPRS Journal of photogrammetry and remote sensing, vol 77 (March 2013)
[article]
Titre : An improved simple morphological filter for the terrain classification of airborne LIDAR data Type de document : Article/Communication Auteurs : Thomas J. Pingel, Auteur ; Keith C. Clarke, Auteur ; William A. Mcbride, Auteur Année de publication : 2013 Article en page(s) : pp 21 - 30 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique de terrain
[Termes IGN] réalité virtuelle
[Termes IGN] semis de pointsRésumé : (Auteur) Terrain classification of LIDAR point clouds is a fundamental problem in the production of Digital Elevation Models (DEMs). The Simple Morphological Filter (SMRF) addresses this problem by applying image processing techniques to the data. This implementation uses a linearly increasing window and simple slope thresholding, along with a novel application of image inpainting techniques. When tested against the ISPRS LIDAR reference dataset, SMRF achieved a mean 85.4% Kappa score when using a single parameter set and 90.02% when optimized. SMRF is intended to serve as a stable base from which more advanced progressive filters can be designed. This approach is particularly effective at minimizing Type I error rates, while maintaining acceptable Type II error rates. As a result, the final surface preserves subtle surface variation in the form of tracks and trails that make this approach ideally suited for the production of DEMs used as ground surfaces in immersive virtual environments. Numéro de notice : A2013-112 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2012.12.002 En ligne : https://doi.org/10.1016/j.isprsjprs.2012.12.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32250
in ISPRS Journal of photogrammetry and remote sensing > vol 77 (March 2013) . - pp 21 - 30[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013031 RAB Revue Centre de documentation En réserve L003 Disponible The influence of scan mode and circle fitting on tree stem detection, stem diameter and volume extraction from terrestrial laser scans / Pyare Pueschel in ISPRS Journal of photogrammetry and remote sensing, vol 77 (March 2013)
[article]
Titre : The influence of scan mode and circle fitting on tree stem detection, stem diameter and volume extraction from terrestrial laser scans Type de document : Article/Communication Auteurs : Pyare Pueschel, Auteur ; Glenn J. Newnham, Auteur ; Gilles Rock, Auteur ; Thomas Udelhoven, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 44 - 56 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] détection automatique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Pseudotsuga menziesii
[Termes IGN] semis de points
[Termes IGN] tronc
[Termes IGN] volume (grandeur)Résumé : (Auteur) Terrestrial laser scanning (TLS) has been used to estimate a number of biophysical and structural vegetation parameters. Of these stem diameter is a primary input to traditional forest inventory. While many experimental studies have confirmed the potential for TLS to successfully extract stem diameter, the estimation accuracies differ strongly for these studies – due to differences in experimental design, data processing and test plot characteristics. In order to provide consistency and maximize estimation accuracy, a systematic study into the impact of these variables is required. To contribute to such an approach, 12 scans were acquired with a FARO photon 120 at two test plots (Beech, Douglas fir) to assess the effects of scan mode and circle fitting on the extraction of stem diameter and volume. An automated tree stem detection algorithm based on the range images of single scans was developed and applied to the data. Extraction of stem diameter was achieved by slicing the point cloud and fitting circles to the slices using three different algorithms (Lemen, Pratt and Taubin), resulting in diameter profiles for each detected tree. Diameter at breast height (DBH) was determined using both the single value for the diameter fitted at the nominal breast height and by a linear fit of the stem diameter vertical profile. The latter is intended to reduce the influence of outliers and errors in the ground level determination. TLS-extracted DBH was compared to tape-measured DBH. Results show that tree stems with an unobstructed view to the scanner can be successfully extracted automatically from range images of the TLS data with detection rates of 94% for Beech and 96% for Douglas fir. If occlusion of trees is accounted for stem detection rates decrease to 85% (Beech) and 84% (Douglas fir). As far as the DBH estimation is concerned, both DBH extraction methods yield estimates which agree with reference measurements, however, the linear fit based approach proved to be more robust for the single scan DBH extraction (RMSE range 1.39–1.74 cm compared to 1.47–2.43 cm). With regard to the different circle fit algorithms applied, the algorithm by Lemen showed the best overall performance (RMSE range 1.39–1.65 cm compared to 1.49–2.43 cm). The Lemen algorithm was also found to be more robust in case of noisy data. Compared to the single scans, the DBH extraction from the merged scan data proved to be superior with significant lower RMSE’s (0.66–1.21 cm). The influence of scan mode and circle fitting is reflected in the stem volume estimates, too. Stem volumes extracted from the single scans exhibit a large variability with deviations from the reference volumes ranging from -34% to 44%. By contrast volumes extracted from the merged scans only vary weakly (-2% to 6%) and show a marginal influence of circle fitting. Numéro de notice : A2013-114 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2012.12.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2012.12.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32252
in ISPRS Journal of photogrammetry and remote sensing > vol 77 (March 2013) . - pp 44 - 56[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013031 RAB Revue Centre de documentation En réserve L003 Disponible Virtual worlds for photogrammetric image-based simulation and learning / Eduardo J. Piatti in Photogrammetric record, vol 28 n° 141 (March - May 2013)
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Titre : Virtual worlds for photogrammetric image-based simulation and learning Type de document : Article/Communication Auteurs : Eduardo J. Piatti, Auteur ; José Luis Lerma, Auteur Année de publication : 2013 Article en page(s) : pp 27 - 42 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] données localisées 3D
[Termes IGN] image aérienne
[Termes IGN] image virtuelle
[Termes IGN] monde virtuel
[Termes IGN] restitution
[Termes IGN] simulation
[Termes IGN] visualisation 3DRésumé : (Auteur) Simulation is a common activity in many fields and pursuits, not only for teaching but also for learning, training, monitoring, research and entertainment, among others. This paper presents the criteria used to develop virtual scenarios for photogrammetric simulation based on both synthetic objects and synthetic images. The workflow used to generate three-dimensional (3D) virtual worlds is presented together with the subsequent reconstruction of the metric perspective images (synthetic scenes) emulating any type of frame camera in any kind of terrestrial or aerial set-up, the latter with an aeroplane, helicopter or unmanned aerial vehicle (UAV). A simulator can be used to create 3D virtual worlds in order to improve an understanding of mission planning, generate synthetic image sequences with suitable overlaps, as well as optimising image data acquisition before undertaking expensive photogrammetric surveys in the field. Numéro de notice : A2013-150 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/phor.12001 Date de publication en ligne : 29/01/2013 En ligne : https://doi.org/10.1111/phor.12001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32288
in Photogrammetric record > vol 28 n° 141 (March - May 2013) . - pp 27 - 42[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-2013011 RAB Revue Centre de documentation En réserve L003 Disponible A framework for the registration and segmentation of heterogeneous lidar data / M. Al-Durgham in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 2 (February 2013)
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Titre : A framework for the registration and segmentation of heterogeneous lidar data Type de document : Article/Communication Auteurs : M. Al-Durgham, Auteur ; A. Habib, Auteur Année de publication : 2013 Article en page(s) : pp 135 - 145 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] densité des points
[Termes IGN] données hétérogènes
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] intégration de données
[Termes IGN] segmentation
[Termes IGN] superposition de donnéesRésumé : (Auteur) Lidar has been established over the past few years as a mainstream tool for the acquisition of three dimensional point data. Besides the conventional mapping missions, lidar has proven to be very useful for a wide spectrum of applications such as forestry, urban planning, structural deformation analysis, and reverse engineering. In the context of a nation-wide dataset, it is safe to assume that multiple laser scanners are under different conditions to collect the data. Current registration and segmentation algorithms assume homogeneity in the local point density and accuracy which is an invalid assumption that cannot be tolerated. As a consequence of the wide range of lidar sensors currently available, it is becoming crucial to develop algorithms for the registration and segmentation of lidar data with significantly varying characteristics (i.e., varying point density and accuracy). In this paper, a methodology for the optimal registration and segmentation of heterogeneous lidar data is presented. An example of integrating airborne and terrestrial laser scans is presented and followed by a discussion of the pros of the integration process. Numéro de notice : A2013-075 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.79.2.135 En ligne : https://doi.org/10.14358/PERS.79.2.135 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32213
in Photogrammetric Engineering & Remote Sensing, PERS > vol 79 n° 2 (February 2013) . - pp 135 - 145[article]Generation and dissemination of a national virtual 3D city and landscape model for the Netherlands / Sander J. Elberink in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 2 (February 2013)PermalinkGround filtering and vegetation mapping using multi-return terrestrial laser scanning / Francesco Pirotti in ISPRS Journal of photogrammetry and remote sensing, vol 76 (February 2013)PermalinkMeet Dr Johannes Riegl / P. Ftizgibbon in GEO: Geoconnexion international, vol 12 n° 2 (february 2013)PermalinkOne billion points in the cloud – an octree for efficient processing of 3D laser scans / Jan Elseberg in ISPRS Journal of photogrammetry and remote sensing, vol 76 (February 2013)PermalinkRetrieval of effective leaf area index in heterogeneous forests with terrestrial laser scanning / G. Zheng in IEEE Transactions on geoscience and remote sensing, vol 51 n° 2 (February 2013)PermalinkSegmentation of terrestrial laser scanning data using geometry and image information / S. Barnea in ISPRS Journal of photogrammetry and remote sensing, vol 76 (February 2013)Permalinkvol 79 n° 2 - February 2013 - Special issue : Three-dimensional national landscape mapping (Bulletin de Photogrammetric Engineering & Remote Sensing, PERS) / American society for photogrammetry and remote sensingPermalinkA 3D geospatial registration service for street level co-visualization of 2D vector maps / Quoc-Dinh Nguyen (2013)PermalinkPermalinkPermalinkCalibration extrinsèque d'un scanner laser multi-fibre / Anthony Wiart (2013)PermalinkPermalinkPermalinkComputer-based synthetic data to assess the tree delineation algorithm from airborne LiDAR survey / L. Wang in Geoinformatica, vol 17 n° 1 (January 2013)PermalinkPermalinkPermalinkPermalinkEuroSDR project Commission 2, Mobile mapping - road environment mapping using mobile laser scanning / Harri Kaartinen (2013)PermalinkEvaluation absolue de méthodes de localisation et de reconstruction panoramique et photogrammétrique d'un tunnel à partir d'un nuage de points de référence appliquée au tunnel-canal de Niderviller / Paul Chavant (2013)PermalinkPermalink