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Titre : Uncertainty propagation for terrestrial mobile laser scanner Type de document : Article/Communication Auteurs : Miloud Mezian , Auteur ; Bruno Vallet , Auteur ; Bahman Soheilian , Auteur ; Nicolas Paparoditis , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2016 Collection : International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, ISSN 1682-1750 num. 41-B3 Projets : 1-Pas de projet / Conférence : ISPRS 2016, Commission 3, 23th international congress 12/07/2016 19/07/2016 Prague République tchèque ISPRS OA Archives Commission 3 Importance : pp 331 - 335 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] géoréférencement direct
[Termes IGN] matrice de covariance
[Termes IGN] propagation d'incertitude
[Termes IGN] semis de pointsRésumé : (auteur) Laser scanners are used more and more in mobile mapping systems. They provide 3D point clouds that are used for object reconstruction and registration of the system. For both of those applications, uncertainty analysis of 3D points is of great interest but rarely investigated in the literature. In this paper we present a complete pipeline that takes into account all the sources of uncertainties and allows to compute a covariance matrix per 3D point. The sources of uncertainties are laser scanner, calibration of the scanner in relation to the vehicle and direct georeferencing system. We suppose that all the uncertainties follow the Gaussian law. The variances of the laser scanner measurements (two angles and one distance) are usually evaluated by the constructors. This is also the case for integrated direct georeferencing devices. Residuals of the calibration process were used to estimate the covariance matrix of the 6D transformation between scanner laser and the vehicle system. Knowing the variances of all sources of uncertainties, we applied uncertainty propagation technique to compute the variance-covariance matrix of every obtained 3D point. Such an uncertainty analysis enables to estimate the impact of different laser scanners and georeferencing devices on the quality of obtained 3D points. The obtained uncertainty values were illustrated using error ellipsoids on different datasets. Numéro de notice : C2016-033 Affiliation des auteurs : LASTIG MATIS (2012-2019) Autre URL associée : vers HAL Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/isprs-archives-XLI-B3-331-2016 Date de publication en ligne : 09/06/2016 En ligne : http://dx.doi.org/10.5194/isprs-archives-XLI-B3-331-2016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91781 3D leaf water content mapping using terrestrial laser scanner backscatter intensity with radiometric correction / Xi Zhu in ISPRS Journal of photogrammetry and remote sensing, vol 110 (December 2015)
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Titre : 3D leaf water content mapping using terrestrial laser scanner backscatter intensity with radiometric correction Type de document : Article/Communication Auteurs : Xi Zhu, Auteur ; Tiejun Wang, Auteur ; Roshanak Darvishzadeh, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 14 – 23 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] correction radiométrique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] intensité lumineuse
[Termes IGN] réflecteur
[Termes IGN] télémétrie laser terrestre
[Termes IGN] teneur en eau de la végétationRésumé : (auteur) Leaf water content (LWC) plays an important role in agriculture and forestry management. It can be used to assess drought conditions and wildfire susceptibility. Terrestrial laser scanner (TLS) data have been widely used in forested environments for retrieving geometrically-based biophysical parameters. Recent studies have also shown the potential of using radiometric information (backscatter intensity) for estimating LWC. However, the usefulness of backscatter intensity data has been limited by leaf surface characteristics, and incidence angle effects. To explore the idea of using LiDAR intensity data to assess LWC we normalized (for both angular effects and leaf surface properties) shortwave infrared TLS data (1550 nm). A reflectance model describing both diffuse and specular reflectance was applied to remove strong specular backscatter intensity at a perpendicular angle. Leaves with different surface properties were collected from eight broadleaf plant species for modeling the relationship between LWC and backscatter intensity. Reference reflectors (Spectralon from Labsphere, Inc.) were used to build a look-up table to compensate for incidence angle effects. Results showed that before removing the specular influences, there was no significant correlation (R2 = 0.01, P > 0.05) between the backscatter intensity at a perpendicular angle and LWC. After the removal of the specular influences, a significant correlation emerged (R2 = 0.74, P Numéro de notice : A2015-890 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.10.001 En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2015.10.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79440
in ISPRS Journal of photogrammetry and remote sensing > vol 110 (December 2015) . - pp 14 – 23[article]Development, calibration and evaluation of a portable and direct georeferenced laser scanning system for kinematic 3D mapping / Erik Heinz in Journal of applied geodesy, vol 9 n° 4 (December 2015)
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Titre : Development, calibration and evaluation of a portable and direct georeferenced laser scanning system for kinematic 3D mapping Type de document : Article/Communication Auteurs : Erik Heinz, Auteur ; Christian Eling, Auteur ; Markus Wieland, Auteur ; Lasse Klingbeil, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2015 Article en page(s) : pp 227 - 243 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] étalonnage d'instrument
[Termes IGN] géoréférencement direct
[Termes IGN] semis de points
[Termes IGN] système de numérisation mobile
[Termes IGN] télémètre laser
[Termes IGN] varianceRésumé : (auteur) In recent years, kinematic laser scanning has become increasingly popular because it offers many benefits compared to static laser scanning. The advantages include both saving of time in the georeferencing and a more favorable scanning geometry. Often mobile laser scanning systems are installed on wheeled platforms, which may not reach all parts of the object. Hence, there is an interest in the development of portable systems, which remain operational even in inaccessible areas. The development of such a portable laser scanning system is presented in this paper. It consists of a lightweight direct georeferencing unit for the position and attitude determination and a small low-cost 2D laser scanner. This setup provides advantages over existing portable systems that employ heavy and expensive 3D laser scanners in a profiling mode. A special emphasis is placed on the system calibration, i. e. the determination of the transformation between the coordinate frames of the direct georeferencing unit and the 2D laser scanner. To this end, a calibration field is used, which consists of differently orientated georeferenced planar surfaces, leading to estimates for the lever arms and boresight angles with an accuracy of mm and one-tenth of a degree. Finally, point clouds of the mobile laser scanning system are compared with georeferenced point clouds of a high-precision 3D laser scanner. Accordingly, the accuracy of the system is in the order of cm to dm. This is in good agreement with the expected accuracy, which has been derived from the error propagation of previously estimated variance components. Numéro de notice : A2015--011 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0011 En ligne : http://dx.doi.org/ 10.1515/jag-2015-0011 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80763
in Journal of applied geodesy > vol 9 n° 4 (December 2015) . - pp 227 - 243[article]Mapping with small UAS: A point cloud accuracy assessment / Charles K. Toth in Journal of applied geodesy, vol 9 n° 4 (December 2015)
[article]
Titre : Mapping with small UAS: A point cloud accuracy assessment Type de document : Article/Communication Auteurs : Charles K. Toth, Auteur ; Grzegorz Jóźków, Auteur ; Dorota A. Grejner-Brzezinska, Auteur Année de publication : 2015 Article en page(s) : pp 213 - 226 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse comparative
[Termes IGN] caractérisation
[Termes IGN] drone
[Termes IGN] géoréférencement direct
[Termes IGN] image optique
[Termes IGN] qualité des données
[Termes IGN] semis de pointsRésumé : (auteur) Interest in using inexpensive Unmanned Aerial System (UAS) technology for topographic mapping has recently significantly increased. Small UAS platforms equipped with consumer grade cameras can easily acquire high-resolution aerial imagery allowing for dense point cloud generation, followed by surface model creation and orthophoto production. In contrast to conventional airborne mapping systems, UAS has limited ground coverage due to low flying height and limited flying time, yet it offers an attractive alternative to high performance airborne systems, as the cost of the sensors and platform, and the flight logistics, is relatively low. In addition, UAS is better suited for small area data acquisitions and to acquire data in difficult to access areas, such as urban canyons or densely built-up environments. The main question with respect to the use of UAS is whether the inexpensive consumer sensors installed in UAS platforms can provide the geospatial data quality comparable to that provided by conventional systems.
This study aims at the performance evaluation of the current practice of UAS-based topographic mapping by reviewing the practical aspects of sensor configuration, georeferencing and point cloud generation, including comparisons between sensor types and processing tools. The main objective is to provide accuracy characterization and practical information for selecting and using UAS solutions in general mapping applications. The analysis is based on statistical evaluation as well as visual examination of experimental data acquired by a Bergen octocopter with three different image sensor configurations, including a GoPro HERO3+ Black Edition, a Nikon D800 DSLR and a Velodyne HDL-32. In addition, georeferencing data of varying quality were acquired and evaluated. The optical imagery was processed by using three commercial point cloud generation tools. Comparing point clouds created by active and passive sensors by using different quality sensors, and finally, by different commercial software tools, provides essential information for the performance validation of UAS technology.Numéro de notice : A2015--010 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0017 En ligne : http://dx.doi.org/10.1515/jag-2015-0017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80762
in Journal of applied geodesy > vol 9 n° 4 (December 2015) . - pp 213 - 226[article]UAV real-time: Data use in a lightweight direct georeferencing system / Christian Eling in GPS world, vol 26 n° 11 (November 2015)
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Titre : UAV real-time: Data use in a lightweight direct georeferencing system Type de document : Article/Communication Auteurs : Christian Eling, Auteur ; Lasse Klingbeil, Auteur ; Markus Wieland, Auteur ; Erik Heinz, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2015 Article en page(s) : pp 44 - 55 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] drone
[Termes IGN] géoréférencement direct
[Termes IGN] GPS en mode cinématique
[Termes IGN] GPS-INS
[Termes IGN] magnétomètre
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] trajectographie par GPSRésumé : (auteur) Direct georeferencing with onboard sensors is less time-consuming for data processing than indirect georeferencing using ground control points, and can supply real-time navigation capability to a UAV. This is very useful for surveying, precision farming or infrastructure inspection. An onboard system for position and attitude determination of lightweight UAVs weighs 240 grams and produces position accuracies better than 5 centimeters and attitude accuracies better than 1 degree. Numéro de notice : A2015--087 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans En ligne : http://gpsworld.com/uav-real-time-data-use-in-a-lightweight-direct-georeferencin [...] Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84804
in GPS world > vol 26 n° 11 (November 2015) . - pp 44 - 55[article]In-orbit geometric calibration and validation of ZY-3 three-line cameras based on CCD-detector look angles / Jinshan Cao in Photogrammetric record, vol 30 n° 150 (June - August 2015)PermalinkInterferometric phase image estimation via sparse coding in the complex domain / Hao Hongxing in IEEE Transactions on geoscience and remote sensing, vol 53 n° 5 (mai 2015)PermalinkMultispectral sensor spectral resolution simulations for generation of hyperspectral vegetation indices from Hyperion data / Prabir Das in Geocarto international, vol 30 n° 5 - 6 (May - July 2015)PermalinkEmploying ground and satellite-based QuickBird data and Random forest to discriminate five tree species in a Southern African Woodland / Samuel Adelabu in Geocarto international, vol 30 n° 3 - 4 (March - April 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)PermalinkExtraction de fragments forestiers et caractérisation de leurs évolutions spatio-temporelles pour évaluer l'effet de l'histoire sur la biodiversité : une approche multi-sources / Pierre-Alexis Herrault (2015)PermalinkImpact of vertical deflection on direct georeferencing of airborne images / M. Pepe in Survey review, vol 47 n° 340 (January 2015)PermalinkPléiades satellites image quality commissioning / Laurent Lebègue in Revue Française de Photogrammétrie et de Télédétection, n° 209 (Janvier 2015)PermalinkTopographic correction of ALOS-PALSAR images using InSAR-derived DEM / Anup Das in Geocarto international, vol 30 n° 1 - 2 (January - February 2015)PermalinkPermalinkRevue des méthodes de prétraitement des données d'imagerie hyperspectrale acquises depuis un drone / Hachem Agili in Geomatica, vol 68 n° 4 (December 2014)PermalinkMethod for orthorectification of terrestrial radar maps / Marion Jaud in ISPRS Journal of photogrammetry and remote sensing, vol 97 (November 2014)PermalinkDirect georeferencing of oblique and vertical imagery in different coordinate systems / H. Zhao in ISPRS Journal of photogrammetry and remote sensing, vol 95 (September 2014)PermalinkCloud removal for remotely sensed images by similar pixel replacement guided with a spatio-temporal MRF model / Qing Cheng in ISPRS Journal of photogrammetry and remote sensing, vol 92 (June 2014)PermalinkEgalisation radiométrique de nuages de points 3D issus de corrélation dense / Luc Girod in Revue Française de Photogrammétrie et de Télédétection, n° 206 (Avril 2014)PermalinkModélisation de la canopée forestière par photogrammétrie depuis des images acquises par drone / Jonathan Lisein in Revue Française de Photogrammétrie et de Télédétection, n° 206 (Avril 2014)PermalinkSegmentation d'images aériennes par coopération LPE-régions et LPE-contours, application à la caractérisation de toitures / Youssef El Merabet in Revue Française de Photogrammétrie et de Télédétection, n° 206 (Avril 2014)PermalinkAutomated geometric correction of multispectral images from high resolution CCD Camera (HRCC) on-board CBERS-2 and CBERS-2B / Chabitha Devarj in ISPRS Journal of photogrammetry and remote sensing, vol 89 (March 2014)PermalinkGeneration of true ortho-images based on virtual worlds: Learning aspects / Eduardo J. Piatti in Photogrammetric record, vol 29 n° 145 (March - May 2014)PermalinkRestoration of information obscured by mountainous shadows through Landsat TM/ETM+ images without the use of DEM data : A new method / Yuan Zhou in IEEE Transactions on geoscience and remote sensing, vol 52 n° 1 tome 1 (January 2014)Permalink