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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)
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 descripteurs IGN] ajustement de paramètres
[Termes descripteurs IGN] appariement d'images
[Termes descripteurs IGN] autocorrélation spatiale
[Termes descripteurs IGN] distorsion d'image
[Termes descripteurs IGN] estimation bayesienne
[Termes descripteurs IGN] étalonnage de chambre métrique
[Termes descripteurs IGN] figuration de la densité
[Termes descripteurs IGN] fonction inverse
[Termes descripteurs IGN] image 2D
[Termes descripteurs IGN] image aérienne
[Termes descripteurs IGN] incertitude géométrique
[Termes descripteurs IGN] longueur focale
[Termes descripteurs IGN] méthode de Monte-Carlo par chaînes de Markov
[Termes descripteurs IGN] modèle numérique de surface
[Termes descripteurs IGN] orientation externe
[Termes descripteurs IGN] photographie numérique
[Termes descripteurs IGN] vue 3D
[Termes descripteurs 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 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 SL Revue Centre de documentation Revues en salle Disponible 081-2020013 DEP-RECP Revue MATIS Dépôt en unité Exclu du prêt 081-2020012 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt
Titre : Global iterative geometric calibration of a linear optical satellite based on sparse GCPs Type de document : Article/Communication Auteurs : Yingdong Pi, Auteur ; Xin Li, Auteur ; Bo Yang, Auteur Année de publication : 2020 Article en page(s) : pp 436 - 446 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes descripteurs IGN] élément d'orientation interne
[Termes descripteurs IGN] erreur systématique
[Termes descripteurs IGN] étalonnage géométrique
[Termes descripteurs IGN] image satellite
[Termes descripteurs IGN] image SPOT-HRV
[Termes descripteurs IGN] itération
[Termes descripteurs IGN] longueur focale
[Termes descripteurs IGN] modèle numérique de surface
[Termes descripteurs IGN] point d'appuiRésumé : (auteur) Independent methods for geometric calibration (GC) have become an important research direction in the field of optical satellite technology. The main purpose of this research is to eliminate dependence on ground calibration sites using relative constraints between images. Based on a systematic analysis of these relative constraints, we found that it was difficult, if not impossible, to completely eliminate ground constraints, although the number of ground control points (GCPs) required can be greatly reduced. To achieve practical GC with high accuracy and low cost, we proposed a new method to compensate for systematic errors in linear optical satellite data acquisition using only the relative constraints between two overlapped images, namely, the corresponding elevation constraints and sparse GCPs. We first demonstrated the feasibility of GC with relative constraints and established an optimized GC model suitable for these relative constraints. We then presented a global iterative method to eliminate inaccuracies in internal calibration caused by the different distributions of GCPs within two images. The nadir (NAD) linear camera on board the Zi-Yuan 3 (ZY-3) satellite was used to evaluate the feasibility of the presented GC method; the results indicated that the present method effectively compensated for systematic errors. Thus, this article demonstrated the feasibility of GC without calibration sites. Numéro de notice : A2020-075 Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2019.2936891 date de publication en ligne : 12/09/2019 En ligne : https://doi.org/10.1109/TGRS.2019.2936891 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94607
in IEEE Transactions on geoscience and remote sensing > vol 58 n° 1 (January 2020) . - pp 436 - 446[article]
Titre : Simulation and analysis of photogrammetric UAV image blocks: influence of camera calibration error Type de document : Article/Communication Auteurs : Yilin Zhou, Auteur ; Ewelina Rupnik Congrès : ISPRS Geospatial Week 2019 (10 - 14 juin 2019; Enschede, Pays-Bas), Commanditaire Année de publication : 2019 Article en page(s) : pp 195 - 200 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes descripteurs IGN] bloc d'images
[Termes descripteurs IGN] compensation par faisceaux
[Termes descripteurs IGN] effet thermique
[Termes descripteurs IGN] erreur systématique
[Termes descripteurs IGN] estimation de pose
[Termes descripteurs IGN] étalonnage de chambre métrique
[Termes descripteurs IGN] étalonnage en vol
[Termes descripteurs IGN] image aérienne oblique
[Termes descripteurs IGN] image de drone
[Termes descripteurs IGN] longueur focale
[Termes descripteurs IGN] photogrammétrie aérienne
[Termes descripteurs IGN] point d'appui
[Termes descripteurs IGN] point de liaison (imagerie)Résumé : (auteur) Unmanned aerial vehicles (UAV) are increasingly used for topographic mapping. The camera calibration for UAV image blocks can be performed a priori or during the bundle block adjustment (self-calibration). For an area of interest with flat, corridor configuration, the focal length of camera is highly correlated with the height of camera. Furthermore, systematic errors of camera calibration accumulate on the longer dimension and cause deformation. Therefore, special precautions must be taken when estimating camera calibration parameters. In this paper, a simulated, error-free aerial image block is generated. error is then added on camera calibration and given as initial solution to bundle block adjustment. Depending on the nature of the error and the investigation purpose, camera calibration parameters are either fixed or re-estimated during the bundle block adjustment. The objective is to investigate how certain errors in the camera calibration impact the accuracy of 3D measurement without the influence of other errors. All experiments are carried out with Fraser camera calibration model being employed. When adopting a proper flight configuration, an error on focal length for the initial camera calibration can be corrected almost entirely during bundle block adjustment. For the case where an erroneous focal length is given for pre-calibration and not re-estimated, the presence of oblique images limits the drift on camera height hence gives better camera pose estimation. Other than that, the error on focal length when neglecting its variation during the acquisition (e.g., due to camera temperature increase) is also investigated; a bowl effect is observed when one focal length is given in camera pre-calibration to the whole image block. At last, a local error is added in image space to simulate camera flaws; this type of error is more difficult to be corrected with the Fraser camera model and the accuracy of 3D measurement degrades substantially. Numéro de notice : A2019-591 Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/isprs-annals-IV-2-W5-195-2019 date de publication en ligne : 29/05/2019 En ligne : https://doi.org/10.5194/isprs-annals-IV-2-W5-195-2019 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94551
in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences > vol IV-2/W5 (may 2019) . - pp 195 - 200[article]
Titre : BIM-Tracker: A model-based visual tracking approach for indoor localisation using a 3D building model Type de document : Article/Communication Auteurs : Debaditya Acharya, Auteur ; Milad Ramezani, Auteur ; Kourosh Khoshelham, Auteur ; Stephan Winter, Auteur Année de publication : 2019 Article en page(s) : pp 157 - 171 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes descripteurs IGN] algorithme de Gauss-Newton
[Termes descripteurs IGN] appariement de données localisées
[Termes descripteurs IGN] corrélation à l'aide de traits caractéristiques
[Termes descripteurs IGN] estimation de pose
[Termes descripteurs IGN] filtre de Kalman
[Termes descripteurs IGN] longueur focale
[Termes descripteurs IGN] Matlab
[Termes descripteurs IGN] méthode des moindres carrés
[Termes descripteurs IGN] modèle 3D du site
[Termes descripteurs IGN] positionnement en intérieur
[Termes descripteurs IGN] trajectoireRésumé : (Auteur) This article presents an accurate and robust visual indoor localisation approach that not only is infrastructure-free, but also avoids accumulation error by taking advantage of (1) the widespread ubiquity of mobile devices with cameras and (2) the availability of 3D building models for most modern buildings. Localisation is performed by matching image sequences captured by a camera, with a 3D model of the building in a model-based visual tracking framework. Comprehensive evaluation of the approach with a photo-realistic synthetic dataset shows the robustness of the localisation approach under challenging conditions. Additionally, the approach is tested and evaluated on real data captured by a smartphone. The results of the experiments indicate that a localisation accuracy better than 10 cm can be achieved by using this approach. Since localisation errors do not accumulate the proposed approach is suitable for indoor localisation tasks for long periods of time and augmented reality applications, without requiring any local infrastructure. A MATLAB implementation can be found on https://github.com/debaditya-unimelb/BIM-Tracker. Numéro de notice : A2019-139 Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.02.014 date de publication en ligne : 27/02/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.02.014 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92473
in ISPRS Journal of photogrammetry and remote sensing > vol 150 (April 2019) . - pp 157 - 171[article]Réservation
Réserver ce documentExemplaires (3)
Code-barres Cote Support Localisation Section Disponibilité 081-2019041 SL Revue Centre de documentation Revues en salle Disponible 081-2019043 DEP-RECP Revue MATIS Dépôt en unité Exclu du prêt 081-2019042 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt
Titre : Efficiently annotating object images with absolute size information using mobile devices Type de document : Article/Communication Auteurs : Martin Hofmann, Auteur ; Marco Seeland, Auteur ; Patrick Mäder, Auteur Année de publication : 2019 Article en page(s) : pp 207 - 224 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes descripteurs IGN] appareil portable
[Termes descripteurs IGN] appariement automatique
[Termes descripteurs IGN] image numérique
[Termes descripteurs IGN] longueur focaleRésumé : (Auteur) The projection of a real world scenery to a planar image sensor inherits the loss of information about the 3D structure as well as the absolute dimensions of the scene. For image analysis and object classification tasks, however, absolute size information can make results more accurate. Today, the creation of size annotated image datasets is effort intensive and typically requires measurement equipment not available to public image contributors. In this paper, we propose an effective annotation method that utilizes the camera within smart mobile devices to capture the missing size information along with the image. The approach builds on the fact that with a camera, calibrated to a specific object distance, lengths can be measured in the object’s plane. We use the camera’s minimum focus distance as calibration distance and propose an adaptive feature matching process for precise computation of the scale change between two images facilitating measurements on larger object distances. Eventually, the measured object is segmented and its size information is annotated for later analysis. A user study showed that humans are able to retrieve the calibration distance with a low variance. The proposed approach facilitates a measurement accuracy comparable to manual measurement with a ruler and outperforms state-of-the-art methods in terms of accuracy and repeatability. Consequently, the proposed method allows in-situ size annotation of objects in images without the need for additional equipment or an artificial reference object in the scene. Numéro de notice : A2018-600 Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s11263-018-1093-3 date de publication en ligne : 24/05/2018 En ligne : https://doi.org/10.1007/s11263-018-1093-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92527
in International journal of computer vision > vol 127 n° 2 (February 2019) . - pp 207 - 224[article]PermalinkPermalinkPermalinkPermalinkCalibration du photothéodolite de l'IGN et traitements d'images pour la surveillance d'ouvrages au sein de l'unité des travaux spéciaux / S. Doz (2005)
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