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Simulation and analysis of photogrammetric UAV image blocks - Influence of camera calibration error / Yilin Zhou in Remote sensing, vol 12 n° 1 (January 2020)
[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 , Auteur ; Christophe Meynard , Auteur ; Christian Thom , Auteur ; Marc Pierrot-Deseilligny , Auteur Année de publication : 2020 Projets : 1-Pas de projet / Article en page(s) : n° 22 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] bloc d'images
[Termes IGN] compensation par faisceaux
[Termes IGN] effet thermique
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] image captée par drone
[Termes IGN] obturateur
[Termes IGN] prise de vue aérienneRésumé : (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 scene and corridor configuration, the focal length of camera is highly correlated with the height of the 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 order to better investigate the impact of camera calibration errors, a synthetic, error-free aerial image block is generated to simulate several issues of interest. Firstly, the erroneous focal length in the case of camera pre-calibration is studied. Nadir images are not able to prevent camera poses from drifting to compensate for the erroneous focal length, whereas the inclusion of oblique images brings significant improvement. Secondly, the case where the focal length varies gradually (e.g., when the camera subject to temperature changes) is investigated. The neglect of this phenomenon can substantially degrade the 3D measurement accuracy. Different flight configurations and flight orders are analyzed, the combination of oblique and nadir images shows better performance. At last, the rolling shutter effect is investigated. The influence of camera rotational motion on the final accuracy is negligible compared to that of the translational motion. The acquisition configurations investigated are not able to mitigate the degradation introduced by the rolling shutter effect. Other solutions such as correcting image measurements or including camera motion parameters in the bundle block adjustment should be exploited. Numéro de notice : A2020-415 Affiliation des auteurs : LASTIG MATIS (2012-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/rs12010022 Date de publication en ligne : 19/12/2019 En ligne : https://doi.org/10.3390/rs12010022 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95503
in Remote sensing > vol 12 n° 1 (January 2020) . - n° 22[article]Underwater calibration in near real time: Focus on detection optimized by AI and selection of calibration patterns / Loïca Avanthey (2020)
Titre : Underwater calibration in near real time: Focus on detection optimized by AI and selection of calibration patterns Type de document : Article/Communication Auteurs : Loïca Avanthey, Auteur ; Laurent Beaudoin, Auteur Editeur : New York : Institute of Electrical and Electronics Engineers IEEE Année de publication : 2020 Conférence : IGARSS 2020, 2020 IEEE International Geoscience and Remote Sensing Symposium 26/09/2020 02/10/2020 Waikoloa, Hawaï Etats-Unis proceedings IEEE Importance : n° 9324519 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie
[Termes IGN] capteur imageur
[Termes IGN] couple stéréoscopique
[Termes IGN] dioptre
[Termes IGN] étalonnage
[Termes IGN] reconstruction 3D
[Termes IGN] scène sous-marineRésumé : (auteur) The 3D reconstruction of underwater scenes from pairs of stereoscopic images requires to model the sensor. To take into account the refraction in the environment and to be compatible with the operational field constraints, we use the compensated pinhole model (the diopter is considered as an additional lens) whose parameters are estimated by an in situ calibration with a pattern. In this article, we propose an optimization by AI of the pattern detection to have real-time feedback and a process which selects on the fly the shots allowing to improve the estimation quality of the model so the manipulation can be stopped when sufficient number of relevant images has been reached. We present the results obtained on a database made up of 60,000 images taken in swimming pools and at sea. Numéro de notice : C2020-039 Affiliation des auteurs : IGN (2020- ) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1109/IGARSS39084.2020.9324519 Date de publication en ligne : 17/02/2021 En ligne : https://doi.org/10.1109/IGARSS39084.2020.9324519 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102625 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 Improvement of photogrammetric accuracy by modeling and correcting the thermal effect on camera calibration / Mehdi Daakir in ISPRS Journal of photogrammetry and remote sensing, vol 148 (February 2019)
[article]
Titre : Improvement of photogrammetric accuracy by modeling and correcting the thermal effect on camera calibration Type de document : Article/Communication Auteurs : Mehdi Daakir , Auteur ; Yilin Zhou , Auteur ; Marc Pierrot-Deseilligny , Auteur ; Christian Thom , Auteur ; Olivier Martin , Auteur ; Ewelina Rupnik , Auteur Année de publication : 2019 Projets : 1-Pas de projet / Article en page(s) : pp 142 - 156 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] CamLight
[Termes IGN] déformation d'image
[Termes IGN] détecteur CMOS
[Termes IGN] effet thermique
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] image captée par drone
[Termes IGN] modèle géométrique de prise de vue
[Termes IGN] photogrammétrie métrologiqueRésumé : (Auteur) This paper presents a new method for improving the geometric accuracy of photogrammetric reconstruction by modeling and correcting the thermal effect on camera image sensor. The objective is to verify that when the temperature of image sensor varies during the acquisition, image deformation induced by the temperature change is quantifiable, modelisable and correctable. A temperature sensor integrated in the camera enables the measurement of image sensor temperature at exposure. It is therefore natural and appropriate to take this effect into account and to finally model and correct it after a calibration step. Nowadays, in cartography applications performed with UAV, the frame rate of acquisitions is continuously increasing. A high frame rate over a long acquisition time can result in an important temperature increase of the image sensor and thus introduces image deformations. The correction of the above-mentioned effect can improve the measurement accuracy. We present three methods to calibrate the thermal effect and experiments on two datasets are carried out to verify the improvement in terms of the photogrammetric accuracy. Numéro de notice : A2019-072 Affiliation des auteurs : LASTIG LOEMI+Ext (2012-2019) Autre URL associée : vers HAL Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.12.012 Date de publication en ligne : 04/01/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.12.012 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92159
in ISPRS Journal of photogrammetry and remote sensing > vol 148 (February 2019) . - pp 142 - 156[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2019021 RAB Revue Centre de documentation En réserve L003 Disponible 081-2019023 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2019022 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt 100% automatic metrology with UAV photogrammetry and embedded GPS, and its application in dike monitoring / Yilin Zhou (2019)
Titre : 100% automatic metrology with UAV photogrammetry and embedded GPS, and its application in dike monitoring Titre original : Métrologie 100 % automatique par photogrammétrie aéroportée légère et GPS de précision permanent et embarqué : application au suivi de digues Type de document : Thèse/HDR Auteurs : Yilin Zhou , Auteur ; Marc Pierrot-Deseilligny , Directeur de thèse ; Christian Thom , Directeur de thèse Editeur : Champs/Marne : Université Paris-Est Marne-la-Vallée UPEM Année de publication : 2019 Importance : 181 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse de Doctorat de l'Université Paris-Est, Sciences et Technologies de l'Information GéographiqueLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] angle nadiral
[Termes IGN] digue
[Termes IGN] données GNSS
[Termes IGN] effet thermique
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] image aérienne
[Termes IGN] image aérienne oblique
[Termes IGN] image captée par drone
[Termes IGN] modélisation 3D
[Termes IGN] obturateur
[Termes IGN] photogrammétrie métrologique
[Termes IGN] point d'appui
[Termes IGN] réseau fluvialIndex. décimale : THESE Thèses et HDR Résumé : (auteur) The development of unmanned aerial vehicle (UAV) platform makes it nowadays a valuable source of data for inspection, surveillance, mapping and 3D modeling issues. UAV photogrammetry opens various new applications in close-range aerial domain and introduces a low-cost alternative to classical manned vehicle photogrammetry. Corridor mapping, one of the fields with substantial importance for UAV photo-grarnmetry, is largely demanded in the surveillance and management of infrastructure assets — highways, railways, waterways and pipelines. Due to the special geometry of the scene, corridor mapping is one case that needs taking precautions. Errors accumu-late easily on the longer dimension of the scene and a bowl effect is often observed; the flatness of the scene introduces strong correlations between parameters to be determi-ned, these two factors together, make it more difficult to obtain high accuracy results in corridor configuration than in classical ones. This thesis is a research project initiated by the CNR, a river concessionary, which has the responsibility of the maintenance and surveillance of its hydraulic facilities, more particularly the dikes. The objective is to apply UAV photogrammetry, which is faster, cheaper and offers a 3D dense reconstruction of the scene, to the monitoring of dikes. While maintaining a high surveying accuracy, a reduced field work, i.e. the number of ground control points (GCPs) is expected. In the first place, simulations are carried out to gain an insight of several problems of corridor mapping that impact the final accuracy. Then, thorough investigations are conducted on three aspects that interest us the most. The first study focuses on the aerial acquisition geometry, discussions are given on the influence of oblique images, nadir images of different flight heights as well as the possibility of an in-flight camera calibration and its application on unfavourable acquisition geometry. The second study aims to improve the acquisition performance for high-end metric cameras. The image deformation introduced by camera temperature variation is investigated and modelled. A method for the correction of this thermal effect is proposed, its performance is eva-luated on both terrestrial and aerial datasets of corridor configuration. The last study interests in the rolling shutter effect for consumer-grade cameras, which is commonly seen in UAV platforms on the market. Two methods are presented to calibrate the camera readout time, a property that is often not given by camera manufacturers. A two-step method is proposed for the correction of rolling shutter effect, its performance is evaluated in both block and corridor configurations. Note de contenu : 1- Introduction en français
2- Introduction
3- State of the art
4- Simulation and analysis
5- Study of aerial acquisition geometry
6- Study of thermal effect
7- Study of rolling shutter effect
8- Conclusion and perspectiveNuméro de notice : 25522 Affiliation des auteurs : LASTIG LOEMI (2012-2019) Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Géophysique : Paris-Est : 2019 Organisme de stage : LaSTIG (IGN) nature-HAL : Thèse DOI : sans Date de publication en ligne : 11/02/2020 En ligne : https://hal.science/tel-02474315v2/ Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94383 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 25522-01 THESE Livre Centre de documentation Thèses Disponible EMVS : Event-based Multi-View Stereo : 3D reconstruction with an event camera in real-time / Henri Rebecq in International journal of computer vision, vol 126 n° 12 (December 2018)PermalinkLa cartographie mobile et le géoréférencement précis de réseaux souterrains / Garance Weller in XYZ, n° 156 (septembre - novembre 2018)PermalinkDrones et SIG / Anonyme in Géomatique expert, n° 122 (mai-juin 2018)PermalinkAdvancement of close range photogrammetry with a portable panoramic image mapping system (PPIMS) / Yung-Chuan Chen in Photogrammetric record, vol 33 n° 162 (June 2018)PermalinkFinding timestamp offsets for a multi-sensor system using sensor observations / Raphael Voges in Photogrammetric Engineering & Remote Sensing, PERS, vol 84 n° 6 (juin 2018)PermalinkBaseline and triangulation geometry in a standard plenoptic camera / Christopher Hahne in International journal of computer vision, vol 126 n° 1 (January 2018)PermalinkCaméra SUSPECT (SUper-SPECTrale) du LOEMI : de la suspicion à la mise à l'épreuve / Olivier Martin (2018)PermalinkPermalinkPermalinkPermalink