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The Influence of camera calibration on nearshore bathymetry estimation from UAV Vvdeos / Gonzalo Simarro in Remote sensing, vol 13 n° 1 (January-1 2021)
[article]
Titre : The Influence of camera calibration on nearshore bathymetry estimation from UAV Vvdeos Type de document : Article/Communication Auteurs : Gonzalo Simarro, Auteur ; Daniel Calvete, Auteur ; Theocharis A. Plomaritis, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 150 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] aberration instrumentale
[Termes IGN] bathymétrie
[Termes IGN] distorsion d'image
[Termes IGN] eaux côtières
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] étalonnage en vol
[Termes IGN] image captée par drone
[Termes IGN] lentille
[Termes IGN] réalité de terrain
[Termes IGN] sondeur monofaisceauRésumé : (auteur) Measuring the nearshore bathymetry is critical in coastal management and morphodynamic studies. The recent advent of Unmanned Aerial Vehicles (UAVs), in combination with coastal video monitoring techniques, allows for an alternative and low cost evaluation of the nearshore bathymetry. Camera calibration and stabilization is a critical issue in bathymetry estimation from video systems. This work introduces a new methodology in order to obtain such bathymetries, and it compares the results to echo-sounder ground truth data. The goal is to gain a better understanding on the influence of the camera calibration and stabilization on the inferred bathymetry. The results show how the proposed methodology allows for accurate evaluations of the bathymetry, with overall root mean square errors in the order of 40 cm. It is shown that the intrinsic calibration of the camera, related to the lens distortion, is the most critical aspect. Here, the intrinsic calibration that was obtained directly during the flight yields the best results. Numéro de notice : A2021-076 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/rs13010150 Date de publication en ligne : 05/01/2021 En ligne : https://doi.org/10.3390/rs13010150 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96814
in Remote sensing > vol 13 n° 1 (January-1 2021) . - n° 150[article]Improved depth estimation for occlusion scenes using a light-field camera / Changkun Yang in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 7 (July 2020)
[article]
Titre : Improved depth estimation for occlusion scenes using a light-field camera Type de document : Article/Communication Auteurs : Changkun Yang, Auteur ; Zhaoqin Liu, Auteur ; Kaichang Di, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 443-456 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] caméra numérique
[Termes IGN] classification pixellaire
[Termes IGN] détection de partie cachée
[Termes IGN] disparité
[Termes IGN] effet de profondeur cinétique
[Termes IGN] lentille
[Termes IGN] méthode de centrage
[Termes IGN] rayonnement lumineux
[Termes IGN] reconstruction 3DRésumé : (Auteur) With the development of light-field imaging technology, depth estimation using light-field cameras has become a hot topic in recent years. Even through many algorithms have achieved good performance for depth estimation using light-field cameras, removing the influence of occlusion, especially multi-occlusion, is still a challenging task. The photo-consistency assumption does not hold in the presence of occlusions, which makes most depth estimation of light-field imaging unreliable. In this article, a novel method to handle complex occlusion in depth estimation of light-field imaging is proposed. The method can effectively identify occluded pixels using a refocusing algorithm, accurately select unoccluded views using the adaptive unoccluded-view identification algorithm, and then improve the depth estimation by computing the cost volumes in the unoccluded views. Experimental results demonstrate the advantages of our proposed algorithm compared with conventional state-of-the art algorithms on both synthetic and real light-field data sets. Numéro de notice : A2020-383 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.86.7.443 Date de publication en ligne : 01/07/2020 En ligne : https://doi.org/10.14358/PERS.86.7.443 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95430
in Photogrammetric Engineering & Remote Sensing, PERS > vol 86 n° 7 (July 2020) . - pp 443-456[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 105-2020071 SL Revue Centre de documentation Revues en salle Disponible Robust pose estimation and calibration of catadioptric cameras with spherical mirrors / Sagi Filin in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 1 (January 2020)
[article]
Titre : Robust pose estimation and calibration of catadioptric cameras with spherical mirrors Type de document : Article/Communication Auteurs : Sagi Filin, Auteur ; Grigory Ilizirov, Auteur ; Bashar Elnashef, Auteur Année de publication : 2020 Article en page(s) : pp 33 - 44 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] estimation de pose
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] flux lumineux
[Termes IGN] lentille
[Termes IGN] méthode robuste
[Termes IGN] miroir
[Termes IGN] reconstruction 3D
[Termes IGN] sphère
[Termes IGN] trilatérationRésumé : (Auteur) Catadioptric cameras broaden the field of view and reveal otherwise occluded object parts. They differ geometrically from central-perspective cameras because of light reflection from the mirror surface. To handle these effects, we present new pose-estimation and reconstruction models for imaging through spherical mirrors. We derive a closed-form equivalent to the collinearity principle via which three methods are established to estimate the system parameters: a resection-based one, a trilateration-based one that introduces novel constraints that enhance accuracy, and a direct and linear transform-based one. The estimated system parameters exhibit improved accuracy compared to the state of the art, and analysis shows intrinsic robustness to the presence of a high fraction of outliers. We then show that 3D point reconstruction can be performed at accurate levels. Thus, we provide an in-depth look into the geometrical modeling of spherical catadioptric systems and practical enhancements of accuracies and requirements to reach them. Numéro de notice : A2020-050 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.86.1.33 Date de publication en ligne : 01/01/2020 En ligne : https://doi.org/10.14358/PERS.86.1.33 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94535
in Photogrammetric Engineering & Remote Sensing, PERS > vol 86 n° 1 (January 2020) . - pp 33 - 44[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 105-2020011 SL Revue Centre de documentation Revues en salle Disponible Geometric model and assessment of a dual‐fisheye imaging system / Mariana Batista Campos in Photogrammetric record, vol 33 n° 162 (June 2018)
[article]
Titre : Geometric model and assessment of a dual‐fisheye imaging system Type de document : Article/Communication Auteurs : Mariana Batista Campos, Auteur ; Antonio Maria Garcia Tommaselli, Auteur ; José Marcato, Auteur ; Eija Honkavaara, Auteur Année de publication : 2018 Article en page(s) : pp 243 - 263 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] chambre panoramique
[Termes IGN] compensation par faisceaux
[Termes IGN] élément d'orientation interne
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] lentille
[Termes IGN] panorama sphériqueRésumé : (Auteur) This paper presents a technique for the calibration of a 360° dual imaging system (Ricoh Theta S) composed of two cameras with fisheye lenses specially mounted in a common structure. The experiments are based on calibration with a bundle adjustment using the equidistant fisheye lens model and relative orientation stability constraints, such as distance, base elements and rotation matrix between individual cameras’ coordinate systems. As a result, an equidistant mathematical model using the Conrady–Brown lens distortion model was shown to be suitable for estimating the interior and relative orientation parameters of the Ricoh Theta S. The main contribution presented in this work is a simultaneous bundle adjustment approach with stability constraints on base elements and rotation matrix angles, which achieved accuracies comparable with conventional photogrammetric calibration with perspective cameras. Numéro de notice : A2018-225 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/phor.12240 Date de publication en ligne : 15/05/2018 En ligne : https://doi.org/10.1111/phor.12240 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90046
in Photogrammetric record > vol 33 n° 162 (June 2018) . - pp 243 - 263[article]Baseline and triangulation geometry in a standard plenoptic camera / Christopher Hahne in International journal of computer vision, vol 126 n° 1 (January 2018)
[article]
Titre : Baseline and triangulation geometry in a standard plenoptic camera Type de document : Article/Communication Auteurs : Christopher Hahne, Auteur ; Amar Aggoun, Auteur ; Vladan Velisavljevic, Auteur ; Susanne Fiebig, Auteur ; Matthias Pesch, Auteur Année de publication : 2018 Article en page(s) : pp 21 - 35 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] capteur imageur
[Termes IGN] lentille
[Termes IGN] ligne de base
[Termes IGN] modèle géométrique de prise de vueRésumé : (Auteur) In this paper, we demonstrate light field triangulation to determine depth distances and baselines in a plenoptic camera. Advances in micro lenses and image sensors have enabled plenoptic cameras to capture a scene from different viewpoints with sufficient spatial resolution. While object distances can be inferred from disparities in a stereo viewpoint pair using triangulation, this concept remains ambiguous when applied in the case of plenoptic cameras. We present a geometrical light field model allowing the triangulation to be applied to a plenoptic camera in order to predict object distances or specify baselines as desired. It is shown that distance estimates from our novel method match those of real objects placed in front of the camera. Additional benchmark tests with an optical design software further validate the model’s accuracy with deviations of less than ±0.33% for several main lens types and focus settings. A variety of applications in the automotive and robotics field can benefit from this estimation model. Numéro de notice : A2018-038 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s11263-017-1036-4 En ligne : https://doi.org/10.1007/s11263-017-1036-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89260
in International journal of computer vision > vol 126 n° 1 (January 2018) . - pp 21 - 35[article]Zoom-dependent camera calibration in digital close-range photogrammetry / Clive Simpson Fraser in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 9 (September 2006)PermalinkManual of photogrammetry, fifth edition / J. Chris Mcglone (2004)PermalinkTraitements d'images provenant de télescopes / S. Reveille (1997)PermalinkOptique / J.P. Perez (1996)PermalinkTraité de photographie / J. Charpie (1989)PermalinkA comparison of methods to measure the modulation transfer function of aerial survey lens systems from the image structures / Leyuan Fang in Photogrammetric Engineering & Remote Sensing, PERS, vol 54 n° 1 (january 1988)PermalinkQuality testing of system cameras / Janne Raty (1988)PermalinkOptique / Daniel Preux (1979)PermalinkOptique, photo identification / Roger Serre (1979)PermalinkOptique à l'usage des étudiants de la classe de mathématiques supérieures et du premier cycle universitaire / R. Annequin (1973)Permalink