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Camera orientation, calibration and inverse perspective with uncertainties: a Bayesian method applied to area estimation from diverse photographs / Grégoire Guillet in ISPRS Journal of photogrammetry and remote sensing, vol 159 (January 2020)
[article]
Titre : Camera orientation, calibration and inverse perspective with uncertainties: a Bayesian method applied to area estimation from diverse photographs Type de document : Article/Communication Auteurs : Grégoire Guillet, Auteur ; Thomas Guillet, Auteur ; Ludovic Ravanel, Auteur Année de publication : 2020 Article en page(s) : pp 237 - 255 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] ajustement de paramètres
[Termes IGN] appariement d'images
[Termes IGN] autocorrélation spatiale
[Termes IGN] distorsion d'image
[Termes IGN] estimation bayesienne
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] figuration de la densité
[Termes IGN] fonction inverse
[Termes IGN] image 2D
[Termes IGN] image aérienne
[Termes IGN] incertitude géométrique
[Termes IGN] longueur focale
[Termes IGN] méthode de Monte-Carlo par chaînes de Markov
[Termes IGN] modèle numérique de surface
[Termes IGN] orientation externe
[Termes IGN] photographie numérique
[Termes IGN] vue 3D
[Termes IGN] vue perspectiveRésumé : (Auteur) Large collections of images have become readily available through modern digital catalogs, from sources as diverse as historical photographs, aerial surveys, or user-contributed pictures. Exploiting the quantitative information present in such wide-ranging collections can greatly benefit studies that follow the evolution of landscape features over decades, such as measuring areas of glaciers to study their shrinking under climate change. However, many available images were taken with low-quality lenses and unknown camera parameters. Useful quantitative data may still be extracted, but it becomes important to both account for imperfect optics, and estimate the uncertainty of the derived quantities. In this paper, we present a method to address both these goals, and apply it to the estimation of the area of a landscape feature traced as a polygon on the image of interest. The technique is based on a Bayesian formulation of the camera calibration problem. First, the probability density function (PDF) of the unknown camera parameters is determined for the image, based on matches between 2D (image) and 3D (world) points together with any available prior information. In a second step, the posterior distribution of the feature area of interest is derived from the PDF of camera parameters. In this step, we also model systematic errors arising in the polygon tracing process, as well as uncertainties in the digital elevation model. The resulting area PDF therefore accounts for most sources of uncertainty. We present validation experiments, and show that the model produces accurate and consistent results. We also demonstrate that in some cases, accounting for optical lens distortions is crucial for accurate area determination with consumer-grade lenses. The technique can be applied to many other types of quantitative features to be extracted from photographs when careful error estimation is important. Numéro de notice : A2020-015 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.11.013 Date de publication en ligne : 02/12/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.11.013 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94404
in ISPRS Journal of photogrammetry and remote sensing > vol 159 (January 2020) . - pp 237 - 255[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2020011 RAB Revue Centre de documentation En réserve L003 Disponible 081-2020013 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2020012 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt Télédétection radar : de l'image d'intensité initiale au choix du mode de calibration des coefficients de diffusion / Jean-Paul Rudant in Revue Française de Photogrammétrie et de Télédétection, n° 219-220 (juin - octobre 2019)
[article]
Titre : Télédétection radar : de l'image d'intensité initiale au choix du mode de calibration des coefficients de diffusion Type de document : Article/Communication Auteurs : Jean-Paul Rudant , Auteur ; Pierre-Louis Frison , Auteur Année de publication : 2019 Projets : 1-Pas de projet / Article en page(s) : pp 19 - 28 Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] coefficient de rétrodiffusion
[Termes IGN] correction d'image
[Termes IGN] correction géométrique
[Termes IGN] correction radiométrique
[Termes IGN] couvert forestier
[Termes IGN] distorsion d'image
[Termes IGN] étalonnage des données
[Termes IGN] géoréférencement
[Termes IGN] télédétection en hyperfréquenceRésumé : (auteur) The current period is characterized by an abundance of free access radar data, the use of which is encouraged and facilitated by space agencies, the latter providing free software for image processing and analysis to users. At the same time, several academic or institutional sites offer explanatory resources (courses, software tutorials) on general or targeted topics intended to facilitate the use of images in most fields of application. In this paper, we wish to address and detail a particular point ; that of the physical concept of the radar measurement, through the various software processing proposed during a sequence of georeferencing-calibration of the images. This sequence, which combines geometrical and radiometric aspects, is found for applications relating to the characterization of the various media present on the surface of the ground or to facilitate the analysis of temporal sequences. After presenting the general aspects related to the power measured at the sensor and the various factors influencing this measurement, we will focus on the user practice, by discussing the different choices of coefficients )3 °, y°, offered during a calibration following a geo-referencing, as well as on the taking into account, or not, slope effects in geometric and radiometric corrections affecting the image. Particular attention is paid to the coefficient 7° whose variations as a function of local incidence are considered very low in the case of dense forests. Numéro de notice : A2019-344 Affiliation des auteurs : UPEM-LASTIG (2016-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : 10.52638/rfpt.2019.454 En ligne : https://doi.org/10.52638/rfpt.2019.454 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93381
in Revue Française de Photogrammétrie et de Télédétection > n° 219-220 (juin - octobre 2019) . - pp 19 - 28[article]Improved camera distortion correction and depth estimation for lenslet light field camera / Changkun Yang in Photogrammetric Engineering & Remote Sensing, PERS, vol 85 n° 3 (March 2019)
[article]
Titre : Improved camera distortion correction and depth estimation for lenslet light field camera Type de document : Article/Communication Auteurs : Changkun Yang, Auteur ; Zhaoqin Liu, Auteur ; Kaichang Di, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 197 - 208 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] caméra numérique
[Termes IGN] carte de profondeur
[Termes IGN] correction géométrique
[Termes IGN] distorsion d'image
[Termes IGN] modèle géométrique de prise de vueRésumé : (Auteur) A light field camera can capture both radiance and angular information, providing a novel solution for depth estimation. The paper proposes two improved methods including distortion model optimization and depth estimation refinement for a lenslet light field camera. For distortion model optimization, a novel 14-parameter distortion model that involves sub-aperture images generation is applied to correct the light field camera images. For depth estimation refinement, an algorithm reducing the high influence of outliers on depth estimation in weak texture regions is proposed based on multi-view stereo matching using the cost volume. Experimental results show the projection error has decreased by about 30% and the depth root-mean-squared error on real world images has decreased by about 42% with our distortion correction method and depth estimation method compared with state of art algorithms. It verifies the correctness and effectiveness of our proposed methods and show significant improvement on accuracy of depth map estimation. Numéro de notice : A2019-148 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.85.3.197 Date de publication en ligne : 01/03/2019 En ligne : https://doi.org/10.14358/PERS.85.3.197 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92477
in Photogrammetric Engineering & Remote Sensing, PERS > vol 85 n° 3 (March 2019) . - pp 197 - 208[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 105-2019031 SL Revue Centre de documentation Revues en salle Disponible
Titre : Image based rendering of large historical image collections Type de document : Article/Communication Auteurs : Evelyn Paiz-Reyes , Auteur Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2019 Projets : Alegoria / Gouet-Brunet, Valérie Conférence : Eurographics 2019, Doctoral consortium, 40th annual conference of the European association for computer graphics 06/05/2019 10/05/2019 Gênes Italie programme doctoral consortium Importance : 4 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse spatio-temporelle
[Termes IGN] base de données d'images
[Termes IGN] distorsion d'image
[Termes IGN] données anciennes
[Termes IGN] iconographie
[Termes IGN] image numérisée
[Termes IGN] information géographique
[Termes IGN] rendu (géovisualisation)
[Termes IGN] visualisation de données
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) This paper states an overview of my dissertation research centered on the continuous immersive visualization and navigation through time and space of large sets of historical photographs. The research aims for: (i) the treatment of scientific obstacles (e.g. data volume, heterogeneity, distortions, and uncertainties) that appear when old pictures are placed in today’s environment; (ii) the visualization (saliently and spatially) of these photos. The main model of the study is image-based rendering IBR, because of its capacity to use imprecise or non-existent geometry (i.e. since a modern 3D scene may differ from a historical one, due to environmental changes over time). The findings of this work may contribute significantly by extending the current IBR models and providing a new innovative way to examine these massive and heterogeneous datasets. Numéro de notice : C2019-073 Affiliation des auteurs : LASTIG MATIS (2012-2019) Thématique : IMAGERIE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans Date de publication en ligne : 05/11/2019 En ligne : https://hal.archives-ouvertes.fr/hal-02301561 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94167 Documents numériques
en open access
Image based rendering... - pdf preprintAdobe Acrobat PDF Comparing historical and contemporary maps : a methodological framework for a cartographic map comparison applied to Swiss maps / Christin Loran in International journal of geographical information science IJGIS, vol 32 n° 11-12 (November - December 2018)
[article]
Titre : Comparing historical and contemporary maps : a methodological framework for a cartographic map comparison applied to Swiss maps Type de document : Article/Communication Auteurs : Christin Loran, Auteur ; Suzette Haegi, Auteur ; Christian Ginzler, Auteur Année de publication : 2018 Article en page(s) : pp 2123 - 2139 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] carte ancienne
[Termes IGN] carte topographique
[Termes IGN] distorsion d'image
[Termes IGN] forêt
[Termes IGN] généralisation cartographique
[Termes IGN] occupation du sol
[Termes IGN] Suisse
[Termes IGN] Zurich (Suisse)
[Vedettes matières IGN] GénéralisationRésumé : (Auteur) Topographic maps are powerful tools for the purpose of identifying land use and cover change (LUCC) as they are among the most reliable representations of past landscapes for the time prior to the existence of aerial photography. In light of the increased availability of historical maps, we argue that there is a need for a standardized process to assess map comparability in a systematic way in order to avoid, or at least minimize, the detection of spurious landscape changes due to incompatible map series. A full understanding of map quality, background and error distributions is fundamental to attain reliable LUCC results. The conceptual framework presented in this study considers the context, distortion and cartographic generalization of topographic maps. Furthermore, it includes an approach to homogenize the level of generalization of landscape elements (e.g. forests) from maps with different scales. To demonstrate its application, we assessed the comparability of seven topographic maps from Canton Zurich covering a time span of 336 years (1664–2000). Overall, for the maps of Canton Zurich, a wall-to-wall comparison of forest cover based on the topographic maps presented here can be problematic for the oldest map from 1664. Based on the results, a wall-to-wall comparison with the later maps is not recommended, due to its substantial distortion. Yet, after re-generalization of natural landscape elements, such as forests, a comparison based on landscape indices is possible, even for the oldest map. Furthermore, our results demonstrate that maps from the mid-19th century onward possess an acceptable level of accuracy. This framework can be applied to a wide range of maps at regional, national, or global levels, providing the opportunity to look at land cover history over multiple centuries. Numéro de notice : A2018-521 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2018.1482553 Date de publication en ligne : 14/06/2018 En ligne : https://doi.org/10.1080/13658816.2018.1482553 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91346
in International journal of geographical information science IJGIS > vol 32 n° 11-12 (November - December 2018) . - pp 2123 - 2139[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2018061 RAB Revue Centre de documentation En réserve L003 Disponible PermalinkThe index array approach and the dual tiled similarity algorithm for UAS hyper-spatial image processing / Lihong Su in Geoinformatica, vol 20 n° 4 (October - December 2016)PermalinkCorrection of ZY-3 image distortion caused by satellite jitter via virtual steady reimaging using attitude data / Mi Wang in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)PermalinkComputation and visualisation of the accuracy of old maps using differential distortion analysis / Manuel Claeys Boùùaert in International journal of geographical information science IJGIS, vol 30 n° 7- 8 (July - August 2016)PermalinkSelf-calibration of digital aerial camera using combined orthogonal models / Hadi Babapour in ISPRS Journal of photogrammetry and remote sensing, vol 117 (July 2016)PermalinkPermalinkDigital surface model generation over urban areas using high resolution satellite SAR imagery : tomographic techniques and their application to 3-Dchange monitoring / Martina Porfiri (2016)PermalinkFusion of space-borne multi-baseline and multi-frequency interferometric results based on extended Kalman filter to generate high quality DEMs / Xiaojie Zhang in ISPRS Journal of photogrammetry and remote sensing, vol 111 (January 2016)PermalinkAnalysis on the dynamic deformations of the images from digital film sequences / Tomasz Markowski in Geodesy and cartography, vol 64 n° 1 (June 2015)PermalinkCorrection of distorsions in YG-12 high-resolution panchromatic images / Yonghua Jiang in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 1 (January 2015)Permalink