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Metaheuristics for the positioning of 3D objects based on image analysis of complementary 2D photographs / Arnaud Flori in Machine Vision and Applications, vol 32 n° 5 (September 2021)
Titre : Metaheuristics for the positioning of 3D objects based on image analysis of complementary 2D photographs Type de document : Article/Communication Auteurs : Arnaud Flori, Auteur ; Hamouche Oulhadj, Auteur ; Patrick Siarry, Auteur Année de publication : 2021 Article en page(s) : n° 105 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme du recuit simulé
[Termes IGN] analyse d'image orientée objet
[Termes IGN] contour
[Termes IGN] image 2D
[Termes IGN] modélisation 3D
[Termes IGN] optimisation par essaim de particules
[Termes IGN] scène 3D
[Termes IGN] triangulationRésumé : (auteur) Today, advances in 3D modeling make it possible to identically reproduce objects, animals, humans and even entire scenes. The broad applications concern video games, virtual reality or augmented reality and cinema, for example. In this article, we propose a new method to build a 3D scene directly from several complementary photographs. The positions of the objects for which we already have a 3D model will be determined by triangulation, thanks to the information extracted from the photographs, such as the outline of the objects on the images. Each pixel of the images is converted into a value that gives its distance to the nearest outline. The 3D model of the objects is then projected on the converted images, and the triangulation is done using a cost function that gives the distance of each projection of the objects to their respective outlines. A projection is considered perfect when its distance to its outlines is null, which means that the cost function gives a score of zero as well. We propose to solve this optimization problem by means of two algorithms, namely Simulated Annealing (SA) and quantum particle swarm optimization (QUAPSO). Numéro de notice : A2021-868 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s00138-021-01229-y Date de publication en ligne : 03/08/2021 En ligne : https://doi.org/10.1007/s00138-021-01229-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99101
in Machine Vision and Applications > vol 32 n° 5 (September 2021) . - n° 105[article]
Titre : Robust detection of non-overlapping ellipses from points with applications to circular target extraction in images and cylinder detection in point clouds Type de document : Article/Communication Auteurs : Reza Maalek, Auteur ; Derek Litchi, Auteur Année de publication : 2021 Article en page(s) : pp 83 - 108 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] chevauchement
[Termes IGN] cylindre
[Termes IGN] détection de cible
[Termes IGN] données localisées 3D
[Termes IGN] ellipticité (géométrie)
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] image 2D
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] méthode robuste
[Termes IGN] Ransac (algorithme)
[Termes IGN] semis de pointsRésumé : (auteur) Detection of non-overlapping ellipses from 2-dimensional (2D) edge points is an essential step towards solving typical photogrammetry problems pertaining to feature detection, calibration, and registration of optical instruments. For instance, circular and spherical black and white calibration and registration targets are represented as ellipses in images. Furthermore, the intersection of a cut plane with cylindrical point clouds generates 2D points following elliptic patterns. To this end, this study proposes a collection of new methods for the automatic and robust detection of non-overlapping ellipses from 2D points. These methods will first be applied to detect circular and spherical targets in images and, second, to detect cylinders in 3D point clouds. The method utilizes the Euclidian ellipticity and a new systematic and generalizable threshold to decide if a set of connected points follow an elliptic pattern. When connected points include outliers, the newly proposed robust Monte Carlo-based ellipse fitting method will be deployed. This method includes three new developments: (i) selecting initial subsamples using a bucketing strategy based on the polar angle of the points; (ii) detecting inlier points by reducing the robust ellipse fitting to a robust circle fitting problem; and (iii) choosing the best inlier set amongst all subsamples using adaptive, systematic, and generalizable selection criteria. A new process is presented to extract cylinders from a point cloud by detecting non-overlapping ellipses from the points projected onto an intersecting cut plane. The proposed methods were compared to established state-of-the-art methods, using simulated and real-world datasets, through the design of four sets of original experiments. The experiments include (i) comparisons of robust ellipse fitting; (ii) sensitivity analysis of the ellipse validation criteria; (iii) comparison of non-overlapping ellipse detection; and (iv) detection of pipes from terrestrial laser scanner point clouds. It was found that the proposed robust ellipse detection was superior to four reliable robust methods, including the popular least median of squares, in both simulated and real-world datasets. The proposed process for detecting non-overlapping ellipses achieved F-measure of 99.3% on real images, compared to 42.4%, 65.6%, and 59.2%, obtained using the methods of Fornaciari, Patraucean, and Panagiotakis, respectively. The proposed cylinder extraction method identified all detectable mechanical pipes in two real-world point clouds collected in laboratory and industrial construction site conditions. The results of this investigation show promise for the application of the proposed methods for automatic extraction of circular targets from images and pipes from point clouds. Numéro de notice : A2021-413 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1016/j.isprsjprs.2021.04.010 Date de publication en ligne : 28/04/2021 En ligne : https://doi.org/10.1016/j.isprsjprs.2021.04.010 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97744
in ISPRS Journal of photogrammetry and remote sensing > vol 176 (June 2021) . - pp 83 - 108[article]
Titre : 3D object detection using lidar point clouds and 2D image object detection Type de document : Mémoire Auteurs : Topi Miekkala, Auteur Editeur : Tampere [Finlande] : Tampere University Année de publication : 2021 Importance : 67 p. Format : 21 x 30 cm Note générale : bibliographie
Master of Science Thesis, Automation EngineeringLangues : Français (fre) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] apprentissage profond
[Termes IGN] détection d'objet
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] fusion de données
[Termes IGN] image 2D
[Termes IGN] navigation autonome
[Termes IGN] objet 3D
[Termes IGN] piéton
[Termes IGN] point d'intérêt
[Termes IGN] segmentation
[Termes IGN] semis de points
[Termes IGN] temps réel
[Termes IGN] vision par ordinateurRésumé : (auteur) This master thesis is about the environmental sensing of an automated vehicle, and its ability to recognize objects of interest such as other road users including pedestrians and other vehicles. Automated driving is a popular and growing field of research, and the continuous increase in the demand of self-driving vehicles requires manufacturers to constantly improve the safety and environmental sensing capabilities of their vehicles. Deep learning neural networks and sensor data fusion are significant tools in the development of detection algorithms of automated vehicles. This thesis presents a method combining neural networks and sensor data fusion to implement 3D object detection into a self-driving car. The method uses an onboard camera sensor and a state of the art 2D image object detector YOLO v4, combining its detections with the data of a lidar sensor, which produces dense point clouds of its environment. These point clouds can be used to estimate distances and locations of surrounding targets. Using inter-sensor calibration between the camera and the lidar, the 3D points outputted by the lidar can be projected on a 2D image, therefore allowing the 3D location estimation of 2D objects detected in an image. The thesis first presents the research questions and the theoretical methods used to implement the algorithm. Some background on automated driving is also presented, followed by the specific research environment and vehicle used in this thesis. The thesis also presents the software implementations and vehicle system integration steps needed to implement everything into a self-driving car to achieve a real-time 3D object detection system. The results of this thesis show that using sensor data fusion, such a system can be integrated fully into a self-driving vehicle, and the processing times of the algorithm can be kept at a real-time rate. Note de contenu : 1- Introduction
2- Methods for sensor data and object detection
3- Autonomous driving and environmental sensing
4- Experiments
5- Evaluation
6- ConclusionNuméro de notice : 28594 Affiliation des auteurs : non IGN Thématique : IMAGERIE/INFORMATIQUE Nature : Mémoire masters divers En ligne : https://trepo.tuni.fi/handle/10024/132285 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99323
Titre : Camera orientation, calibration and inverse perspective with uncertainties: a Bayesian method applied to area estimation from diverse photographs Type de document : Article/Communication Auteurs : Grégoire Guillet, Auteur ; Thomas Guillet, Auteur ; Ludovic Ravanel, Auteur Année de publication : 2020 Article en page(s) : pp 237 - 255 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] ajustement de paramètres
[Termes IGN] appariement d'images
[Termes IGN] autocorrélation spatiale
[Termes IGN] distorsion d'image
[Termes IGN] estimation bayesienne
[Termes IGN] étalonnage de chambre métrique
[Termes IGN] figuration de la densité
[Termes IGN] fonction inverse
[Termes IGN] image 2D
[Termes IGN] image aérienne
[Termes IGN] incertitude géométrique
[Termes IGN] longueur focale
[Termes IGN] méthode de Monte-Carlo par chaînes de Markov
[Termes IGN] modèle numérique de surface
[Termes IGN] orientation externe
[Termes IGN] photographie numérique
[Termes IGN] vue 3D
[Termes IGN] vue perspectiveRésumé : (Auteur) Large collections of images have become readily available through modern digital catalogs, from sources as diverse as historical photographs, aerial surveys, or user-contributed pictures. Exploiting the quantitative information present in such wide-ranging collections can greatly benefit studies that follow the evolution of landscape features over decades, such as measuring areas of glaciers to study their shrinking under climate change. However, many available images were taken with low-quality lenses and unknown camera parameters. Useful quantitative data may still be extracted, but it becomes important to both account for imperfect optics, and estimate the uncertainty of the derived quantities. In this paper, we present a method to address both these goals, and apply it to the estimation of the area of a landscape feature traced as a polygon on the image of interest. The technique is based on a Bayesian formulation of the camera calibration problem. First, the probability density function (PDF) of the unknown camera parameters is determined for the image, based on matches between 2D (image) and 3D (world) points together with any available prior information. In a second step, the posterior distribution of the feature area of interest is derived from the PDF of camera parameters. In this step, we also model systematic errors arising in the polygon tracing process, as well as uncertainties in the digital elevation model. The resulting area PDF therefore accounts for most sources of uncertainty. We present validation experiments, and show that the model produces accurate and consistent results. We also demonstrate that in some cases, accounting for optical lens distortions is crucial for accurate area determination with consumer-grade lenses. The technique can be applied to many other types of quantitative features to be extracted from photographs when careful error estimation is important. Numéro de notice : A2020-015 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.11.013 Date de publication en ligne : 02/12/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.11.013 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94404
in ISPRS Journal of photogrammetry and remote sensing > vol 159 (January 2020) . - pp 237 - 255[article]Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 081-2020011 RAB Revue Centre de documentation En réserve L003 Disponible 081-2020013 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2020012 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt
Titre : 2D image processing applied to 3D LiDAR point clouds Titre original : Traitement d’image 2D appliqué à des nuages de points LiDAR 3D Type de document : Thèse/HDR Auteurs : Pierre Biasutti Editeur : Bordeaux : Université de Bordeaux Année de publication : 2019 Importance : 204 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse pour l'obtention du grade de Docteur en Informatique, Université de BordeauxLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] détection de partie cachée
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] image 2D
[Termes IGN] image RVB
[Termes IGN] orthoimage
[Termes IGN] recalage de données localisées
[Termes IGN] segmentation sémantique
[Termes IGN] semis de points
[Termes IGN] Stéréopolis
[Termes IGN] système de numérisation mobile
[Termes IGN] topologie capteur
[Termes IGN] visibilitéIndex. décimale : THESE Thèses et HDR Résumé : (auteur) L'intérêt toujours grandissant pour les données cartographiques fiables, notamment en milieu urbain, a motivé le développement de systèmes de cartographie mobiles terrestres. Ces systèmes sont conçus pour l'acquisition de données de très haute précision, telles que des nuages de points LiDAR 3D et des images optiques. La multitude de données, ainsi que leur diversité, rendent complexe le traitement des données issues de ce type de systèmes. Cette thèse se place dans le contexte du traitement de l'image appliqué au nuages de points LiDAR 3D issus de ce type de système. Premièrement, nous nous intéressons à des images issues de la projection de nuages de points LiDAR dans des grilles de pixels 2D régulières. Ces projections créent généralement des images éparses, dans lesquelles l'information de certains pixels n'est pas connue. Nous proposons alors différentes méthodes pour des applications telles que la génération d'orthoimages haute résolution, l'imagerie RGB-D et l'estimation de la visibilité des points d'un nuage. De plus, nous proposons d'exploiter la topologie d'acquisition des capteurs LiDAR pour produire des images de faible résolution : les range-images. Ces images offrent une représentation efficace et canonique du nuage de points, tout en étant directement accessibles à partir du nuage de points. Nous montrons comment ces images peuvent être utilisées pour simplifier, voire améliorer, des méthodes pour le recalage multi-modal, la segmentation, la désoccultation et la détection 3D. Note de contenu : Introduction
1- Image processing on sparse projection of 3D LiDAR point clouds
2- Image processing on 3D LiDAR point clouds in sensor topology
ConclusionNuméro de notice : 25458 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE/INFORMATIQUE Nature : Thèse française Note de thèse : Thèse de Doctorat : Informatique : Bordeaux : 2019 Organisme de stage : Laboratoire Bordelais de Recherche en Informatique LaBRI nature-HAL : Thèse DOI : sans En ligne : https://tel.hal.science/tel-02369991 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94227 
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