Descripteur
Documents disponibles dans cette catégorie (729)
![](./images/expand_all.gif)
![](./images/collapse_all.gif)
Etendre la recherche sur niveau(x) vers le bas
Model based signal processing techniques for nonconventional optical imaging systems / Daniele Picone (2021)
![]()
Titre : Model based signal processing techniques for nonconventional optical imaging systems Type de document : Thèse/HDR Auteurs : Daniele Picone, Auteur ; Mauro Dalla Mura, Directeur de thèse Editeur : Grenoble [France] : Université Grenoble Alpes Année de publication : 2021 Importance : 364 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse pour obtenir le grade de Docteur de l'Université Grenoble Alpes, spécialité : Signal Image Parole TélécomsLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] acquisition comprimée
[Termes IGN] fusion d'images
[Termes IGN] image hyperspectrale
[Termes IGN] inférence statistique
[Termes IGN] interférométrie
[Termes IGN] méthode du maximum de vraisemblance (estimation)
[Termes IGN] mosaïque d'images
[Termes IGN] pouvoir de résolution géométrique
[Termes IGN] pouvoir de résolution spectrale
[Termes IGN] problème inverse
[Termes IGN] reconstruction d'image
[Termes IGN] régression non linéaire
[Termes IGN] spectromètre imageur
[Termes IGN] traitement du signalIndex. décimale : THESE Thèses et HDR Résumé : (auteur) There is an increasing demand for images with higher spectral and spatial resolution for applications in several domains such as health, environment, quality checking and natural disasters monitoring. Hyperspectral imagery provides the necessary spectral diversity to recover the composition of materials on site for applications such as the detection of fires, anomalies, chemical agents, targets and changes in the scene.The requirement for cheaper and more compact devices (e.g. to be embarked on low cost satellites and airborne platform) which are capable of capturing this information has led to the development of nonconventional innovative design concepts to overcome the technological limitations of traditional cameras. Data acquired by such novel imaging devices following the computational imaging paradigm are typically not readily exploitable for the final application. A computational phase is hence needed for extracting useful information from the raw acquisitions.This thesis addresses this issue by setting up an inversion problem. The general approach is to characterize the data fidelity term with a physical model, describing the underlying optical transformations performed by the device. The challenge is then shifted on the regularization step to properly characterizes the features of the quantities of interest and improve the accuracy of the estimation, which can be tackled with variational techniques.The analysis is applied to two novel concepts for nonconventional optical devices. The first one is a novel compressed acquisition imaging system based on color filter arrays, which embeds information from sensors with different spatial and spectral characteristics into a single mosaiced product. As opposed to existing compressed sensing based devices, the goal is not to recover the original uncompressed multiresolution sources, but instead to directly recover a synthetic fused image with both high spatial and spectral resolution.The proposed solution relies on the total variation regularization and is the subject of a detailed analysis, comparing its compressive power with straightforward software alternatives, evaluating its performances as the amount of channels changes, and validating its efficiency in comparison to state of the art methods when applied to classical fusion or mosaicing algorithms separately.The second class of devices is based on the ImSPOC patent, a design concept for a low finesse snapshot imaging spectrometer based on the interferometry of Fabry-Pérot. Its ideal behaviour follows the principle of the Fourier Transform Spectroscopy, as its acquisition can be interpreted as a sampled version of an interferogram, arranged across different sub-images distributed on the same focal plane.After defining a physical model based on optical geometry, its validity is evaluated over real acquisitions by setting up a Bayesian inference problem to determine its parameters, with approaches based on maximum likelihood estimators, regular-grid searches and nonlinear regression.A variety of preliminary tests are then carried out on the inversion method, with approaches based on singular value decomposition and sparse-inducing regularizers, accompanied by a analysis of their robustness to model mismatches. Note de contenu : 1- Introduction
2- Inverse problems theory
3- Signal processing of multimodal data
4- Joint fusion and demosaicing of compressed multiresolution acquisitions
5- Optics foundations for the ImSPOC acquisition system
6- Data processing pipeline of ImSPOC acquisitions
7- ConclusionsNuméro de notice : 28691 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Signal Image Parole Télécoms : Grenoble : 2021 Organisme de stage : GIPSA-lab DOI : sans En ligne : https://hal.science/tel-03596486v1 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100170
Titre : Multispectral object detection Type de document : Thèse/HDR Auteurs : Heng Zhang, Auteur ; Elisa Fromont, Directeur de thèse ; Sébastien Lefèvre, Directeur de thèse Editeur : Rennes : Université de Rennes 1 Année de publication : 2021 Importance : 114 p. Format : 21 x 30 cm Note générale : Bibliographie
Thèse présentée en vue de l’obtention du grade de docteur en Informatique de l'Université de Rennes 1Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] apprentissage profond
[Termes IGN] chambre de prise de vue thermique
[Termes IGN] détection d'objet
[Termes IGN] données d'entrainement sans étiquette
[Termes IGN] efficacité
[Termes IGN] fusion de données multisource
[Termes IGN] image multibande
[Termes IGN] précision de la classification
[Termes IGN] qualité du modèle
[Termes IGN] segmentation sémantiqueIndex. décimale : THESE Thèses et HDR Résumé : (Auteur) Only using RGB cameras for automatic outdoor scene analysis is challenging when, for example, facing insufficient illumination or adverse weather. To improve the recognition reliability, multispectral systems add additional cameras (e.g. infra-red) and perform object detection from multispectral data. Although multispectral scene analysis with deep learning has been shown to have a great potential, there are still many open research questions and it has not been widely deployed in industrial contexts. In this thesis, we investigated three main challenges about multispectral object detection: (1) the fast and accurate detection of objects of interest from images; (2) the dynamic and adaptive fusion of information from different modalities;(3) low-cost and low-energy multispectral object detection and the reduction of its manual annotation efforts. In terms of the first challenge, we first optimize the label assignment of the object detection training with a mutual guidance strategy between the classification and localization tasks; we then realize an efficient compression of object detection models including the teacher-student prediction disagreements in a feature-based knowledge distillation framework. With regard to the second challenge, three different multispectral feature fusion schemes are proposed to deal with the most difficult fusion cases where different cameras provide contradictory information. For the third challenge, a novel modality distillation framework is firstly presented to tackle the hardware and software constraints of current multispectral systems; then a multi-sensor-based active learning strategy is designed to reduce the labeling costs when constructing multispectral datasets. Note de contenu : 1. Introduction
1.1 Context and motivations
1.2 Thesis outline
2. Deep learning background
2.1 General object detection
2.2 Multispectral object detection
2.3 Knowledge distillation
2.4 Active learning
2.5 Datasets
3. Efficient object detection on embedded devices
3.1 Best practices for training object detection models
3.2 Mutual Guidance for Anchor Matching
3.3 Prediction Disagreement aware Feature Distillation
3.4 Experimental results
4. Information fusion from multispectral data
4.1 Multispectral Fusion with Cyclic Fuse-and-Refine
4.2 Progressive Spectral Fusion
4.3 Experimental results for CFR and PS-Fuse
4.4 Guided Attentive Feature Fusion
4.5 Experimental results for GAFF
5. Sensors and annotations: low cost multispectral data processing
5.1 Deep Active Learning from Multispectral Data
5.2 Low-cost Multispectral Scene Analysis with Modality Distillation
6. Conclusions and future works
6.1 Conclusions
6.2 Application to remote sensing data
6.3 PerspectivesNuméro de notice : 26765 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Informatique : Rennes 1 : 2021 Organisme de stage : (IRISA) INRIA nature-HAL : Thèse DOI : sans Date de publication en ligne : 17/01/2022 En ligne : https://hal.science/tel-03530257/ Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99855 Vers un protocole de calibration de caméras statiques à l'aide d'un drone / Jean-François Villeforceix (2021)
![]()
Titre : Vers un protocole de calibration de caméras statiques à l'aide d'un drone Type de document : Article/Communication Auteurs : Jean-François Villeforceix, Auteur ; Benjamin Bigot, Auteur Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2021 Conférence : ORASIS 2021, 18e journées francophones des jeunes chercheurs en vision par ordinateur 13/09/2021 17/09/2021 Lac de Saint-Ferréol France programme Note générale : J.F. Villeforceix relève à la fois de l'IGN et du Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile. Langues : Français (fre) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] caméra numérique
[Termes IGN] chaîne de traitement
[Termes IGN] drone
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] point d'appui
[Termes IGN] positionnement statiqueRésumé : (auteur) Nous présentons un protocole de calibration d’une caméra statique. Ce type de caméra est singulier en photogrammétrie car l’utilisateur ne peut pas modifier son point de vue. Lorsque ce dernier n’est pas orienté vers des références connues, il devient alors impossible de calculer les paramètres de la caméra. Le BEA est amené à travailler sur des données issues de caméras statiques pour lesquelles il ne dispose que d’informations basiques (modèle, focale). La difficulté réside à la fois dans l’imprévisibilité des configurations rencontrées et les contraintes opérationnelles liées à l’enquête. Un protocole de calibration adapté à ces caméras spécifiques a été défini afin de répondre à ces 2 problématiques propres au BEA. Numéro de notice : C2021-071 Affiliation des auteurs : IGN+Ext (2020- ) Thématique : IMAGERIE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans En ligne : https://tel.archives-ouvertes.fr/IGN-ENSG/hal-03339675v1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99544 Towards online UAS‐based photogrammetric measurements for 3D metrology inspection / Fabio Menna in Photogrammetric record, vol 35 n° 172 (December 2020)
![]()
[article]
Titre : Towards online UAS‐based photogrammetric measurements for 3D metrology inspection Type de document : Article/Communication Auteurs : Fabio Menna, Auteur ; Erica Nocerino, Auteur ; Fabio Remondino, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 467 - 486 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] antenne
[Termes IGN] caméra 3D temps-de-vol
[Termes IGN] caméra numérique
[Termes IGN] image captée par drone
[Termes IGN] métrologie
[Termes IGN] photogrammétrie aérienne
[Termes IGN] plan de vol
[Termes IGN] positionnement cinématique en temps réelRésumé : (auteur) This paper presents the development of a vision metrology system for high‐accuracy three‐dimensional measurements of large structures requiring dimensional tolerancing. The proposed system integrates a V‐STARS N platinum photogrammetric system from Geodetic Systems, a DJI M600 Pro UAS with Ronin‐MX gimbal and a dual antenna for real‐time kinematic positioning. The paper presents the system architecture and the developed software for camera network simulation and image acquisition. As an acquisition scenario, a large dish parabolic antenna is simulated. The benefits of the developed procedure include the ability to handle obstacle avoidance and self‐occlusions and, employing a rigorous camera network simulation approach, to overcome the limitations of currently available flight planning commercial tools that are mainly conceived for mapping applications. Future work will consider extensive testing of the platform in real‐case scenarios. Numéro de notice : A2020-799 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/phor.12338 Date de publication en ligne : 18/11/2020 En ligne : https://doi.org/10.1111/phor.12338 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96720
in Photogrammetric record > vol 35 n° 172 (December 2020) . - pp 467 - 486[article]Structure from motion for complex image sets / Mario Michelini in ISPRS Journal of photogrammetry and remote sensing, vol 166 (August 2020)
![]()
[article]
Titre : Structure from motion for complex image sets Type de document : Article/Communication Auteurs : Mario Michelini, Auteur ; Helmut Mayer, Auteur Année de publication : 2020 Article en page(s) : pp 140 - 152 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] appariement d'images
[Termes IGN] arbre aléatoire minimum
[Termes IGN] caméra numérique
[Termes IGN] distorsion d'image
[Termes IGN] étalonnage d'instrument
[Termes IGN] fusion de données multisource
[Termes IGN] itération
[Termes IGN] jeu de données
[Termes IGN] orientation
[Termes IGN] reconstruction 3D
[Termes IGN] SIFT (algorithme)
[Termes IGN] structure-from-motionRésumé : (auteur) This paper presents an approach for Structure from Motion (SfM) for unorganized complex image sets. To achieve high accuracy and robustness, image triplets are employed and an (approximate) internal camera calibration is assumed to be known. The complexity of an image set is determined by the camera configurations which may include wide as well as weak baselines. Wide baselines occur for instance when terrestrial images and images from small Unmanned Aerial Systems (UAS) are combined. The resulting large (geometric/radiometric) distortions between images make image matching difficult possibly leading to an incomplete result. Weak baselines mean an insufficient distance between cameras compared to the distance of the observed scene and give rise to critical camera configurations. Inappropriate handling of such configurations may lead to various problems in triangulation-based SfM up to total failure. The focus of our approach lies on a complete linking of images even in case of wide or weak baselines. We do not rely on any additional information such as camera configurations, Global Positioning System (GPS) or an Inertial Navigation System (INS). As basis for generating suitable triplets to link the images, an iterative graph-based method is employed formulating image linking as the search for a terminal Steiner minimum tree in the line graph. SIFT (Lowe, 2004) descriptors are embedded into Hamming space for fast image similarity ranking. This is employed to limit the number of pairs to be geometrically verified by a computationally and more complex wide baseline matching method (Mayer et al., 2012). Critical camera configurations which are not suitable for geometric verification are detected by means of classification (Michelini and Mayer, 2019). Additionally, we propose a graph-based approach for the optimization of the hierarchical merging of triplets to efficiently generate larger image subsets. By this means, a complete, 3D reconstruction of the scene is obtained. Experiments demonstrate that the approach is able to produce reliable orientation for large image sets comprising wide as well as weak baseline configurations. Numéro de notice : A2020-355 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2020.05.020 Date de publication en ligne : 12/06/2020 En ligne : https://doi.org/10.1016/j.isprsjprs.2020.05.020 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95242
in ISPRS Journal of photogrammetry and remote sensing > vol 166 (August 2020) . - pp 140 - 152[article]Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 081-2020081 RAB Revue Centre de documentation En réserve L003 Disponible 081-2020083 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2020082 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt A history of laser scanning, Part 1: space and defense applications / Adam P. Spring in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 7 (July 2020)
PermalinkImproved depth estimation for occlusion scenes using a light-field camera / Changkun Yang in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 7 (July 2020)
PermalinkGeometric modelling and calibration of a spherical camera imaging system / Derek D. Lichti in Photogrammetric record, vol 35 n° 170 (June 2020)
PermalinkMultiscale Intensity Propagation to Remove Multiplicative Stripe Noise From Remote Sensing Images / Hao Cui in IEEE Transactions on geoscience and remote sensing, vol 58 n° 4 (April 2020)
PermalinkGeneralized tensor regression for hyperspectral image classification / Jianjun Liu in IEEE Transactions on geoscience and remote sensing, vol 58 n° 2 (February 2020)
PermalinkLandslide susceptibility mapping using maximum entropy and support vector machine models along the highway corridor, Garhwal Himalaya / Vijendra Kumar Pandey in Geocarto international, vol 35 n° 2 ([01/02/2020])
PermalinkOptimising drone flight planning for measuring horticultural tree crop structure / Yu-Hsuan Tu in ISPRS Journal of photogrammetry and remote sensing, vol 160 (February 2020)
PermalinkA two-step approach for the correction of rolling shutter distortion in UAV photogrammetry / Yilin Zhou in ISPRS Journal of photogrammetry and remote sensing, vol 160 (February 2020)
PermalinkPermalinkPermalink