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Le plug-in ACYOTB : l'orthorectification open source de précision / Valerio Baiocchi in Géomatique expert, n° 132-133 (janvier - septembre 2020)
[article]
Titre : Le plug-in ACYOTB : l'orthorectification open source de précision Type de document : Article/Communication Auteurs : Valerio Baiocchi, Auteur ; Francesca Giannone, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 50 - 63 Note générale : bibliographie
article original en anglais en libre accès : https://doi.org/10.3390/ijgi9010011Langues : Français (fre) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] image spatiale
[Termes IGN] Orfeo Tool Box
[Termes IGN] orthorectification
[Termes IGN] QGISRésumé : (auteur) [original abstract] High-resolution satellite images must undergo a geometric rectification process in order to be used for metrical purposes. This operation, called orthorectification, is necessary because of deformations mainly due to camera distortions and acquisition geometry. To correctly orthorectify an image, it is necessary to accurately reconstruct the photogrammetric-acquisition characteristics and the image position with respect to a reference system connected to the ground. This operation, called orientation, can be done using various mathematical models such as rigorous, rational polynomial function (RPF), and rational polynomial coefficient, or, according to some authors, rapid positioning coefficient (RPC) models. Orientation and orthorectification are usually performed within specific commercial software, but in QGIS, these complex operations can be performed using the open libraries of the Orfeo Tool Box (OTB). Unfortunately, instructions given by OTB developers lead to scarce results. In fact, the procedure proposed in OTB does not allow for the full exploitation of the potential of RPC models, on which OTB itself is based. As OTB is open-source software, a plugin was developed to overcome these limitations and exploit its full potential. In fact, OTB interfaces are unfortunately essential, and some necessary functions are missing. Therefore, a new QGIS plugin was developed in order to run the entire process in the most photogrammetrically and statistically correct way, and, at the same time, to simplify the relative procedures. Numéro de notice : A2020-863 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99185
in Géomatique expert > n° 132-133 (janvier - septembre 2020) . - pp 50 - 63[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 265-2020011 RAB Revue Centre de documentation En réserve L003 Disponible IFN-001-P002238 PER Revue Nogent-sur-Vernisson Salle périodiques Exclu du prêt 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]A low‐cost open‐source workflow to generate georeferenced 3D SfM photogrammetric models of rocky outcrops / Laurent Froideval in Photogrammetric record, vol 34 n° 168 (December 2019)
[article]
Titre : A low‐cost open‐source workflow to generate georeferenced 3D SfM photogrammetric models of rocky outcrops Type de document : Article/Communication Auteurs : Laurent Froideval, Auteur ; Kevin Pedoja, Auteur ; Franck Garestier, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 365 - 384 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] falaise
[Termes IGN] front rocheux
[Termes IGN] géoréférencement
[Termes IGN] GNSS en mode différentiel
[Termes IGN] image captée par drone
[Termes IGN] logiciel libre
[Termes IGN] modélisation 3D
[Termes IGN] Normandie (région 2016)
[Termes IGN] Open MVG
[Termes IGN] point d'appui
[Termes IGN] structure-from-motionRésumé : (auteur) Structure‐from‐Motion (SfM) software and unmanned aerial vehicles (UAVs) have been increasingly adopted in the geosciences. The current mainstream generation of 3D models is still expensive as it relies on UAVs, Differential Global Navigation Satellite System (DGNSS) ground control points and commercial software. This paper proposes an end‐to‐end reproducible SfM workflow with minimal legal, financial or field issues. The procedure avoids both UAVs and DGNSS and relies on open‐source software. Interlocked models of a rocky shore in Normandy, France were generated at different scales and point densities, being georeferenced using free spatial data. A spherical target was used for scaling and assessing the relative accuracy, which was better than 1 cm. Numéro de notice : A2019-576 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/phor.12297 Date de publication en ligne : 27/11/2019 En ligne : https://doi.org/10.1111/phor.12297 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94459
in Photogrammetric record > vol 34 n° 168 (December 2019) . - pp 365 - 384[article]The utility of terrestrial photogrammetry for assessment of tree volume and taper in boreal mixedwood forests / Christopher Mulverhill in Annals of Forest Science, Vol 76 n° 3 (September 2019)
[article]
Titre : The utility of terrestrial photogrammetry for assessment of tree volume and taper in boreal mixedwood forests Type de document : Article/Communication Auteurs : Christopher Mulverhill, Auteur ; Nicholas C. Coops, Auteur ; Piotr Tompalski, Auteur ; Christopher W. Bater, Auteur ; Adam R. Dick, Auteur Année de publication : 2019 Article en page(s) : pp 76 - 83 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] Abies balsamea
[Termes IGN] Alberta (Canada)
[Termes IGN] allométrie
[Termes IGN] betula papyrifera var. papyrifera
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] diamètre des arbres
[Termes IGN] données dendrométriques
[Termes IGN] forêt boréale
[Termes IGN] hauteur des arbres
[Termes IGN] image terrestre
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] peuplement mélangé
[Termes IGN] photogrammétrie terrestre
[Termes IGN] Picea glauca
[Termes IGN] Picea mariana
[Termes IGN] Pinus contorta
[Termes IGN] Populus tremuloides
[Termes IGN] semis de points
[Termes IGN] volume en boisRésumé : (auteur) Key Message: This study showed that digital terrestrial photogrammetry is able to produce accurate estimates of stem volume and diameter across a range of species and tree sizes that showed strong correspondence when compared with traditional inventory techniques. This paper demonstrates the utility of the technology for characterizing trees in complex habitats such as boreal mixedwood forests.
Context: Accurate knowledge of tree stem taper and volume are key components of forest inventories to manage and study forest resources. Recent developments have seen the increasing use of ground-based point clouds, including from digital terrestrial photogrammetry (DTP), to provide accurate estimates of these key forest attributes.
Aims: In this study, we evaluated the utility of DTP based on a small set of photos (12 per tree) for estimating stem volume and taper on a set of 15 trees from 6 different species (Populus tremuloides, Picea glauca, Pinus contorta latifolia, Betula papyrifera, Picea mariana, Abies balsamea) in a boreal mixedwood forest in Alberta, Canada.
Methods: We constructed accurate photogrammetric point clouds and derived taper and volume from three point cloud–based methods, which were then compared with estimates from conventional, field-based measurements. All methods were evaluated for their accuracy based on field-measured taper and volume of felled trees.
Results: Of the methods tested, we found that the point cloud–derived diameters in a taper curve matching approach performed the best at estimating diameters at the lowest parts of the stem ( 50% of total height). Using the field-measured DBH and height as inputs to calculate stem volume yielded the most accurate predictions; however, these were not significantly different from the best point cloud-based estimates.
Conclusion: The methodology confirmed that using a small set of photographs provided accurate estimates of individual tree DBH, taper, and volume across a range of species and size gradients (10.8–40.4 cm DBH).Numéro de notice : A2019-303 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-019-0852-9 Date de publication en ligne : 08/08/2019 En ligne : https://doi.org/10.1007/s13595-019-0852-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93226
in Annals of Forest Science > Vol 76 n° 3 (September 2019) . - pp 76 - 83[article]Time-lapse photogrammetry of distributed snow depth during snowmelt / Simon Filhol in Water resources research, vol 55 n° 9 (September 2019)
[article]
Titre : Time-lapse photogrammetry of distributed snow depth during snowmelt Type de document : Article/Communication Auteurs : Simon Filhol, Auteur ; Alexis Perret , Auteur ; Luc Girod , Auteur ; Guillaume Sutter, Auteur ; Thomas V. Schuler, Auteur ; John F. Burkhart, Auteur Année de publication : 2019 Projets : 3-projet - voir note / Note générale : bibliographie
This work was supported by the Norwegian Research Council—Enhancing Snow Competency of Models and Operators(ESCYMO) project (NFR 244024), the University of Oslo eInfrastructure Competence Hub Geohive, and the European Research Council under the European Union's Seventh FrameworkProgram (FP/2007-2013)/ERC GrantAgreement 320816. This work forms a contribution to LATICE, which is a strategic research initiative funded by the Faculty of Mathematics and Natural Sciences at the University of Oslo. The source code of the software is available at this site (https://github.com/ArcticSnow/photo4D). Data are freely available from Zenodo.org (Filhol et al., 2018).FILHOL ET AL.7925Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] chaîne de traitement
[Termes IGN] code source libre
[Termes IGN] eau de fonte
[Termes IGN] manteau neigeux
[Termes IGN] Norvège
[Termes IGN] profondeur
[Termes IGN] semis de pointsRésumé : (auteur) Characterizing snowmelt both spatially and temporally from in situ observation remains a challenge. Available sensors (i.e., sonic ranger, lidar, airborne photogrammetry) provide either time series of local point measurements or sporadic surveys covering larger areas. We propose a methodology to recover from a minimum of three synchronized time-lapse cameras changes in snow depth and snow cover extent over area smaller or equivalent to 0.12 km2. Our method uses photogrammetry to compute point clouds from a set of three or more images and automatically repeat this task for the entire time series. The challenges were (1) finding an optimal experimental setup deployable in the field, (2) estimating the error associated with this technique, and (3) being able to minimize the input of manual work in the data processing pipeline. Developed and tested in the field in Finse, Norway, over 1 month during the 2018 melt season, we estimated a median melt of 2.12 ± 0.48 m derived from three cameras 1.2 km away from the region of interest. The closest weather station recorded 1.94 m of melt. Other parameters like snow cover extent and duration could be estimated over a 300 × 400m region. The software is open source and applicable to a broader range of geomorphologic processes like glacier dynamic, snow accumulation, or any other processes of surface deformation, with the conditions of (1) having fixed visible points within the area of interest and (2) resolving sufficient surface textures in the photographs. Numéro de notice : A2019-663 Affiliation des auteurs : ENSG+Ext (2012-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2018WR024530 Date de publication en ligne : 19/08/2019 En ligne : https://doi.org/10.1029/2018WR024530 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99691
in Water resources research > vol 55 n° 9 (September 2019)[article]Digital surface model generation from high resolution multi-view stereo satellite imagery / Ke Gong in Photogrammetric Engineering & Remote Sensing, PERS, vol 85 n° 5 (May 2019)PermalinkFlexible photogrammetric computations using modular bundle adjustment : The chain rule and the collinearity equations / Niclas Börlin in Photogrammetric Engineering & Remote Sensing, PERS, vol 85 n° 5 (May 2019)PermalinkRobust structure from motion based on relative rotations and tie points / Xin Wang in Photogrammetric Engineering & Remote Sensing, PERS, vol 85 n° 5 (May 2019)PermalinkAutomatic sensor orientation using horizontal and vertical line feature constraints / Yanbiao Sun in ISPRS Journal of photogrammetry and remote sensing, vol 150 (April 2019)PermalinkPatch-based detection of dynamic objects in CrowdCam images / Gagan Kanojia in The Visual Computer, vol 35 n° 4 (April 2019)PermalinkNumérisation et modélisation 3D du Jardin d’Hiver du Musée de la Faïence de Sarreguemines / Valentin Girardet in XYZ, n° 158 (mars 2019)PermalinkPermalinkApports des techniques photogrammétriques à l'étude du dynamisme des structures volcaniques du piton de la Fournaise / Allan Derrien (2019)PermalinkPermalinkPermalink