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Titre : Diffusion anisotrope et inpainting d’orthophotographies LiDAR mobile Type de document : Article/Communication Auteurs : Pierre Biasutti , Auteur ; Jean-François Aujol, Auteur ; Mathieu Brédif
, Auteur ; Aurélie Bugeau, Auteur
Editeur : Association française pour la reconnaissance et l'interprétation des formes AFRIF Année de publication : 2016 Conférence : RFIA 2016, 20e conférence Reconnaissance des Formes et Intelligence Artificielle 27/06/2016 01/07/2016 Clermond-Ferrand France OA Proceedings Importance : 2 p. Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] anisotropie
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] inpainting
[Termes IGN] occultation du signal
[Termes IGN] orthoimage
[Termes IGN] réflectance
[Termes IGN] route
[Termes IGN] semis de pointsMots-clés libres : ANR-10-IDEX-03-02 Résumé : (auteur) Cet article présente un processus pour la production jointe d’orthophotographie de réflectance et de hauteur à très grande résolution (1cm) à partir d’un levé laser mobile. La projection verticale du nuage de points LiDAR sur une grille de pixels 2D, après filtrage des points du sol, génère deux images éparses et bruitées (réflectance et de hauteur). Nous proposons d’en dériver une image dense par diffusion anisotrope couplée à un débruitage par régularisation TVL 1. De plus, nous adaptons une méthode d’inpainting afin de combler les zones d’occultation en tirant parti de la reconstruction couplée réflectance/hauteur et d’un a priori d’alignement entre les structures à inpainter. Numéro de notice : C2016-017 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84606 Documents numériques
en open access
Diffusion anisotrope et inpainting - pdf auteurAdobe Acrobat PDFDigital surface model generation over urban areas using high resolution satellite SAR imagery : tomographic techniques and their application to 3-Dchange monitoring / Martina Porfiri (2016)
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Titre : Digital surface model generation over urban areas using high resolution satellite SAR imagery : tomographic techniques and their application to 3-Dchange monitoring Type de document : Thèse/HDR Auteurs : Martina Porfiri, Auteur ; Mattia Crespi, Auteur ; Laurent Ferro-Famil, Auteur Editeur : Rennes : Université de Rennes 1 Année de publication : 2016 Autre Editeur : Rennes : Université Bretagne Loire Importance : 137 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse de l'Université de Rennes 1 sous le sceau de l’Université Bretagne Loire, En Cotutelle Internationale avec l'Université de Rome 1 « La Sapienza », Traitement du signal et télécommunications.Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] détection de changement
[Termes IGN] distorsion d'image
[Termes IGN] image à haute résolution
[Termes IGN] image radar moirée
[Termes IGN] milieu urbain
[Termes IGN] modèle numérique de surface
[Termes IGN] Paris (75)
[Termes IGN] polarisation
[Termes IGN] reconstruction 3D du bâti
[Termes IGN] réflectivité
[Termes IGN] semis de points
[Termes IGN] tomographie radarIndex. décimale : THESE Thèses et HDR Résumé : (auteur) The urbanization and the management of urban environment and its periphery become one of the most crucial issues in developed and developing countries. In these circumstances, remote sensing data are an important source of information that reflects interactions between human beings and their environment. Given their complete independence from logistic constraints on the ground, illumination (daylight), and weather (clouds) conditions, Synthetic Aperture Radar (SAR) satellite systems may provide important contributions in complex environments 3-D reconstruction. The new generation of high resolution SAR sensors as COSMO-SkyMed, TerraSAR-X and RADARSAT-2 allowed to acquire high resolution SAR imagery. Here the attention is put on the 3-D imaging technique called SAR Tomography: starting from a stack of images collected using multibaseline data performed in interferometric configuration, such a technique allows to retrieve height information forming a synthetic aperture in the elevation direction in order to achieve a substantially improved resolution. The present PhD thesis is focused on the high potentialities of tomographic techniques in 3-D change monitoring and characterization for complex and dense built-up areas using basic mono-dimensional estimators as Beamforming, Capon and MUSIC combined to very high satellite SAR resolution imagery. 2-D and 3-D analysis have been presented over the urban area of Paris using TerraSAR-X data at high resolution and single polarisation. Being mainly focused on the 3-D tomographic techniques, in the presented work 4-D methods, such as compressive sensing (CS), have not been taken into account. At first, the analysis of the interferometric quality of the processed data set has been performed and results showed good mean coherence values within the entire stack. The extraction of 2-D tomograms over different azimuth-profile has showed the capabilities to distinguish more than one scatterer within the same resolution cell and to reconstruct the vertical building profiles. Successively, a global 3-D characterization both in term of buildings heights and vertical reflectivity has been performed in order to develop a monitoring tool for the changes of single structures. Moreover, the possibility to correct the geometric distortions due to the layover (that strongly affects such kind of scenarios) and to determine the information about the number of scatterers (up to three) and the corresponding reflectivity within one resolution cell have been evaluated. Moreover an innovative time stability analysis of the observed scene have been carried out in order to detect the stable and unstable scatterers. Globally, the investigations showed noisier and sparser point clouds for the Capon method, whereas better capabilities for the Beamforming and MUSIC ones. Indeed, it was possible to detect different scatterers located within the same resolution cell and to resolve pixels affected by the layover. This has lead to perform a good reconstruction of building shape and location and a good estimation of their elevation. The 3-D time stability analysis demonstrated the possibility to monitor the 3-D change depending on the time. Eventually, it is possible to assert that processing high resolution SAR data allows to achieve a strong improvement in 3-D imaging capabilities. It has been demonstrated the potentialities of TomoSAR technique in distortions correction and in 3-D change monitoring using basic mono-dimensional estimators. Note de contenu : 1- Introduction
2- SAR: Synthetic Aperture Radar
3- 3-D SAR imaging
4- SAR Tomography
5- 2-D analysis and results
6- 3-D analysis and results
7- Conclusions and outlookNuméro de notice : 25879 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Traitement du signal et télécommunications : Université Bretagne Loire : 2016 Organisme de stage : Institut d’Electronique et de Télécommunications de Rennes nature-HAL : Thèse DOI : sans En ligne : http://www.theses.fr/2016REN1S035 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95690 Effectiveness of observation-domain sidereal filtering for GPS precise point positioning / Christopher Atkins in GPS solutions, vol 20 n° 1 (January 2016)
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Titre : Effectiveness of observation-domain sidereal filtering for GPS precise point positioning Type de document : Article/Communication Auteurs : Christopher Atkins, Auteur ; Marek Ziebart, Auteur Année de publication : 2016 Article en page(s) : pp 111 - 122 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] correction du trajet multiple
[Termes IGN] phase
[Termes IGN] positionnement ponctuel précis
[Termes IGN] propagation ionosphérique
[Termes IGN] séisme
[Termes IGN] variance d'Allan
[Vedettes matières IGN] Traitement de données GNSSRésumé : (Auteur) Sidereal filtering is a technique used to reduce errors caused by multipath in the positioning of static receivers via the Global Positioning System (GPS). It relies upon the receiver and its surrounding environment remaining static from one day to the next and takes advantage of the approximately sidereal repeat time of the GPS constellation geometry. The repeating multipath error can thus be identified, usually in the position domain, and largely removed from the following day. We describe an observation-domain sidereal filter algorithm that operates on undifferenced ionospheric-free GPS carrier phase measurements to reduce errors caused by multipath. It is applied in the context of high-rate (1 Hz) precise point positioning of a static receiver. An observation-domain sidereal filter (ODSF) is able to account for the slightly different repeat times of each GPS satellite, unlike a position-domain sidereal filter (PDSF), and can hence be more effective at reducing high-frequency multipath error. Using 8-h long datasets of GPS measurements from two different receivers with different antenna types and contrasting environments, the ODSF algorithm is shown overall to yield a position time series 5–10 % more stable, in terms of Allan deviation, than a PDSF over nearly all time intervals below about 200 s in length. This may be particularly useful for earthquake and tsunami early warning systems where the accurate measurement of small displacements of the ground over the period of just a few minutes is crucial. However, the sidereal filters are also applied to a third dataset during which two short episodes of particularly high-frequency multipath error were identified. These two periods are analyzed in detail and illustrate the limitations of using sidereal filters with important implications for other methods of correcting for multipath at the observation level. Numéro de notice : A2016-605 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0473-1 En ligne : http://dx.doi.org/10.1007/s10291-015-0473-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81806
in GPS solutions > vol 20 n° 1 (January 2016) . - pp 111 - 122[article]Entwicklung einer direkten Georeferenzierungseinheit zur Positions- und Orientierungbestimmung leichter UAVs in Eichzeit / Christian Eling (2016)
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Titre : Entwicklung einer direkten Georeferenzierungseinheit zur Positions- und Orientierungbestimmung leichter UAVs in Eichzeit Type de document : Thèse/HDR Auteurs : Christian Eling, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2016 Collection : DGK - C, ISSN 0065-5325 num. 788 Importance : 107 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-5200-0 Note générale : bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] drone
[Termes IGN] géoréférencement direct
[Termes IGN] GPS-INS
[Termes IGN] magnétomètre
[Termes IGN] onde porteuse
[Termes IGN] photogrammétrie aérienne
[Termes IGN] semis de points
[Termes IGN] système de numérisation mobileRésumé : (auteur) In recent years, Unmanned Aerial Vehicles (UAVs) have been used increasingly as mobile mapping platforms for kinematic applications in the field of geodesy. For this purpose a UAV is usually equipped with a mapping sensor, such as a camera or a laserscanner. A major step to make the collected data useful for surveying applications is the georeferencing, which associates the images or range measurements and the derived products (point clouds, orthofotos, 3D models) with a spatial reference. In this dissertation the development of a direct georeferencing system for real-time position and attitude determination of lightweight UAVs is presented. The term „direct" means that the georeferencing is based on an onboard multi-sensor system. Sensors, which are typically used in this context, are GPS (Global Positioning System) receivers, inertial sensors and magnetometers. For geodetic UAV-applications Micro-UAVs are usually applied, which have a weight limit of 5 kg. Therefore, weight, size and power supply constraints play an important role here. As a result of these limitations inertial sensors based on MEMS (Micro Electro Mechanical System) technology are mostly used. This technology enables the compliance with size and weight limits, but it also leads to significant drift effects in the position and attitude determination after a short period of time. To bound these drift effects and to be able to provide high accuracies (e.g. position: 5 cm, attitude: 0.5 deg) in the direct georeferencing of a Micro-UAV, a high availability of precise GPS carrier phase measurements is crucially important. As a consequence the following aspects will be addressed in this dissertation:
• GPS carrier phase measurements are ambiguous by an unknown number of integer cycles. These so called ambiguities have to be resolved after every loss of lock of the satellite signals to fully exploit the high accuracies of the carrier phase observables. Since the satellite signals are interrupted frequently during kinematic applications, procedures are developed, implemented and evaluated, which enable a fast ambiguity resolution and allow for a high availability of CPS carrier phase measurements under challenging GPS measurement conditions.
• With the aim to realize high accuracies and a high robustness, redundant information from several sensors is integrated in a sensible manner in sensorfusion algorithms In order to be able to deal with challenging GPS measurement conditions, the sensorfusion is realized at the level of GPS raw measurements in a tightly-coupled GPS/MEMS-IMU integration algorithm. In this way GPS carrier phase measurements can even be used, if less than four satellites are visible, which also increases the availability of a precise position estimation. The accuracy improvements of a tightly-coupled over a loosely-coupled integration during challenging GPS measurement conditions are investigated.
• The algorithms are implemented on a multi-sensor system, which has been developed for the direct georeferencing of lightweight UAVs in this dissertation. Results of flight tests and measurements with a portable test system demonstrate that the developed direct georeferencing system leads to position accuracies of less than 5 cm and attitude (roll, pitch, yaw) accuracies of less than 0.2 deg, if GPS carrier-phase measurements are available. Overall, this dissertation gives detailed insights into the development of algorithms and a multi-sensor system for the direct georeferencing of lightweight UAVs in real-time. The findings gained in this thesis are not only valid for the position and attitude determination of lightweight UAVs but also for other mobile platforms, such as cars, ships, airplanes or rail-borne vehicles. Therefore, this work makes an important contribution to a current trend in the field of engineering geodesy, where mapping, monitoring and also setting-out is more and more realized using mobile mapping systems.Numéro de notice : 17380 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère Note de thèse : Dissertation : : Rheinische Friedrich-Wilhelms-Universität Bonn : 2016 DOI : sans En ligne : https://dgk.badw.de/fileadmin/user_upload/Files/DGK/docs/c-788.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84793 External error modelling with combined model in terrestrial laser scanning / J. Wang in Survey review, vol 48 n° 346 (January 2016)
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Titre : External error modelling with combined model in terrestrial laser scanning Type de document : Article/Communication Auteurs : J. Wang, Auteur ; H. Kutterer, Auteur ; X. Fang, Auteur Année de publication : 2016 Article en page(s) : pp 40 - 50 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] itération
[Termes IGN] modèle de Gauss-Helmert
[Termes IGN] réfraction atmosphérique
[Termes IGN] télémétrie laser sur satellite
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) Terrestrial laser scanning (TLS) is a promising tool in geodetic applications. Data quality of outdoor TLS measurements is considerably limited by external errors caused by atmospheric variations and object related factors. In this study, external models related to atmospheric refraction, beam wander and incidence angle were introduced and integrated into a seven-parameter similarity transformation (7PST) model to compose a combined model. The combined model was rigorously adjusted by an iterative Gauss–Helmert (GH) model primarily to estimate external calibration parameters and transformation parameters simultaneously. In the application on a dam surface, a t-test showed that a significant external calibration parameter was the range scale, which mainly corresponded with the incidence angle model. The precision of estimated representative points was improved by approximately 50% with the proposed method. The presented models show a great potential for detecting external errors and registering multiple scans in outdoor applications. Numéro de notice : A2016-045 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/00396265.2015.1097589 En ligne : https://doi.org/10.1080/00396265.2015.1097589 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79638
in Survey review > vol 48 n° 346 (January 2016) . - pp 40 - 50[article]Forcing scale invariance in multipolarization SAR change detection / Vincenzo Carotenuto in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)
PermalinkPermalinkPermalinkPassive microwave remote sensing of soil moisture based on dynamic vegetation scattering properties for AMSR-E / Jinyang Du in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)
PermalinkPermalinkRadar based classification prior to biomass retrieval from P-Band SAR data / Pierre-Louis Frison (2016)
PermalinkRemote Sensing Observations of Continental Surfaces, ch. 6. Airborne lidar data processing / Clément Mallet (2016)
PermalinkStatic GNSS precise point positioning using free online services for Africa / Anis Abdallah in Survey review, vol 48 n° 346 (January 2016)
PermalinkPermalinkTraitement du signal marégraphique par analyse harmonique pour la détermination d'une référence altimétrique pour l'Algérie / A. Rami in Bulletin des sciences géographiques, n° 30 (2015 - 2016)
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