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Summarizing large scale 3D mesh for urban navigation / Imeen Ben Salah in Robotics and autonomous systems, vol 152 (June 2022)
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Titre : Summarizing large scale 3D mesh for urban navigation Type de document : Article/Communication Auteurs : Imeen Ben Salah, Auteur ; Sébastien Kramm, Auteur ; Cédric Demonceaux, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 104037 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme ICP
[Termes IGN] carte en 3D
[Termes IGN] données lidar
[Termes IGN] entropie
[Termes IGN] image hémisphérique
[Termes IGN] image RVB
[Termes IGN] information sémantique
[Termes IGN] localisation basée vision
[Termes IGN] maillage
[Termes IGN] navigation autonome
[Termes IGN] précision géométrique (imagerie)
[Termes IGN] précision radiométrique
[Termes IGN] profondeur
[Termes IGN] Rouen
[Termes IGN] saillance
[Termes IGN] zone urbaineRésumé : (auteur) Cameras have become increasingly common in vehicles, smartphones, and advanced driver assistance systems. The areas of application of these cameras in the world of intelligent transportation systems are becoming more and more varied: pedestrian detection, line crossing detection, navigation, …A major area of research currently focuses on mapping that is essential for localization and navigation. However, this step generates an important problem of memory management. Indeed, the memory space required to accommodate the map of a small city is measured in tens gigabytes. In addition, several providers today are competing to produce High-Definition (HD) maps. These maps offer a rich and detailed representation of the environment for highly accurate localization. However, they require a large storage capacity and high transmission and update costs. To overcome these problems, we propose a solution to summarize this type of map by reducing the size while maintaining the relevance of the data for navigation based on vision only. The summary consists in a set of spherical images augmented by depth and semantic information and allowing to keep the same level of visibility in every directions. These spheres are used as landmarks to offer guidance information to a distant agent. They then have to guarantee, at a lower cost, a good level of precision and speed during navigation. Some experiments on real data demonstrate the feasibility for obtaining a summarized map while maintaining a localization with interesting performances. Numéro de notice : A2022-290 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1016/j.robot.2022.104037 Date de publication en ligne : 03/02/2022 En ligne : https://doi.org/10.1016/j.robot.2022.104037 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100335
in Robotics and autonomous systems > vol 152 (June 2022) . - n° 104037[article]Automatic extraction of building geometries based on centroid clustering and contour analysis on oblique images taken by unmanned aerial vehicles / Leilei Zhang in International journal of geographical information science IJGIS, vol 36 n° 3 (March 2022)
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Titre : Automatic extraction of building geometries based on centroid clustering and contour analysis on oblique images taken by unmanned aerial vehicles Type de document : Article/Communication Auteurs : Leilei Zhang, Auteur ; Guoxin Wang, Auteur ; Weijian Sun, Auteur Année de publication : 2022 Article en page(s) : pp 453 - 475 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse de groupement
[Termes IGN] classification barycentrique
[Termes IGN] classification non dirigée
[Termes IGN] détection de contours
[Termes IGN] détection du bâti
[Termes IGN] extraction automatique
[Termes IGN] image captée par drone
[Termes IGN] image oblique
[Termes IGN] modèle numérique de surface
[Termes IGN] orthophotocarte
[Termes IGN] précision géométrique (imagerie)Résumé : (auteur) This paper introduces a method based on centroid clustering and contour analysis to extract area and height measurements on buildings from the 3D model generated by oblique images. The method comprises three steps: (1) extract the contour plane from the fused data of the digital surface model (DSM) and digital orthophoto map (DOM); (2) identify building contour clusters based on the number of centroids contained in each category determined by mean-shift centroid clustering; (3) remove the mis-identified contours in a given building contour cluster by a contour analysis and obtain the geometric information of the building using map algebra. The proposed approach was tested against four datasets. Compared with other results, the detection has effective completeness, correctness, quality, and higher geometric accuracy. The maximum average relative error of building height and area extraction is less than 8%. The method is fast for a large-scale collection of building attributes and improves the applicability of oblique photography in GIS. Numéro de notice : A2022-205 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2021.1937632 Date de publication en ligne : 14/06/2021 En ligne : https://doi.org/10.1080/13658816.2021.1937632 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100020
in International journal of geographical information science IJGIS > vol 36 n° 3 (March 2022) . - pp 453 - 475[article]
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Titre : Nanosatellites, des Lego dans l’espace Type de document : Article/Communication Auteurs : Laurent Polidori, Auteur Année de publication : 2021 Article en page(s) : pp 19 - 19 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Satellites artificiels
[Termes IGN] nanosatellite
[Termes IGN] qualité d'image
[Termes IGN] satellite d'observation de la Terre
[Termes IGN] secteur spatial
[Termes IGN] télédétection spatialeRésumé : (Auteur) Observer la planète avec des constellations de satellites miniaturisés présente des avantages et des inconvénients. Numéro de notice : A2021-891 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtSansCL DOI : sans Date de publication en ligne : 01/12/2021 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99230
in Géomètre > n° 2197 (décembre 2021) . - pp 19 - 19[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 063-2021111 SL Revue Centre de documentation Revues en salle Disponible Influence of flight altitude and control points in the georeferencing of images obtained by unmanned aerial vehicle / Lucas Santos Santana in European journal of remote sensing, vol 54 n° 1 (2021)
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Titre : Influence of flight altitude and control points in the georeferencing of images obtained by unmanned aerial vehicle Type de document : Article/Communication Auteurs : Lucas Santos Santana, Auteur ; Gabriel Araújo E Silva Ferraz, Auteur ; Diego Bedin Marin, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 59 - 71 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] altitude
[Termes IGN] capteur aérien
[Termes IGN] géoréférencement
[Termes IGN] hauteur de vol
[Termes IGN] image captée par drone
[Termes IGN] Minas Gerais (Brésil)
[Termes IGN] modèle numérique de terrain
[Termes IGN] photogrammétrie aérienne
[Termes IGN] point d'appui
[Termes IGN] précision géométrique (imagerie)Résumé : (auteur) This study aimed to explore the influence of flight altitude, density, and distribution of ground control points (GCPs) on the digital terrain model (DTM) in surveys conducted by unmanned aerial vehicles (UAVs). A total of 144 photogrammetric projects consisting of 399 aerial photos were carried out in a 2 ha area. These photogrammetric projects involved six GCP distributions (edge, center, diagonal, parallel, stratified, and random), six GCP densities, and four flight altitudes (30, 60, 90, and 120 m). The response surface methodology was used to find interference factors and total root-mean-square error (RMSEt) as well. The 60 m flight altitude presented was the most efficient. Central GCP distribution was observed to have low precision. Using stratified and random edge distributions, 10 GCPs are recommended to achieve geometric precision below 0.07 m at any flight height. However, for studies requiring up to 0.07 m precision, the best distribution was parallel with 4 GCPs at any altitude. Diagonal positioning of the GCPs showed RMSEt values below 0.11 m with 4 GCPs at any altitude. A good distribution of GCPs was found to be important, but the density of GCPs per image was more relevant when obtaining a lower RMSEt. Numéro de notice : A2021-155 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/22797254.2020.1845104 Date de publication en ligne : 10/01/2021 En ligne : https://doi.org/10.1080/22797254.2020.1845104 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97018
in European journal of remote sensing > vol 54 n° 1 (2021) . - pp 59 - 71[article]
Titre : 3D point cloud compression Type de document : Thèse/HDR Auteurs : Chao Cao, Auteur ; Titus Zaharia, Directeur de thèse ; Marius Preda, Directeur de thèse Editeur : Paris : Institut Polytechnique de Paris Année de publication : 2021 Importance : 165 p. Format : 21 x 30 cm Note générale : Bibliographie
Thèse de doctorat de l’Institut polytechnique de Paris, Spécialité InformatiqueLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] compression d'image
[Termes IGN] corrélation automatique de points homologues
[Termes IGN] couleur (variable spectrale)
[Termes IGN] état de l'art
[Termes IGN] objet 3D
[Termes IGN] précision géométrique (imagerie)
[Termes IGN] scène 3D
[Termes IGN] segmentation d'image
[Termes IGN] semis de points
[Termes IGN] structure-from-motionIndex. décimale : THESE Thèses et HDR Résumé : (Auteur) With the rapid growth of multimedia content, 3D objects are becoming more and more popular. Most of the time, they are modeled as complex polygonal meshes or dense point clouds, providing immersive experiences in different industrial and consumer multimedia applications. The point cloud, which is easier to acquire than mesh and is widely applicable, has raised many interests in both the academic and commercial worlds.A point cloud is a set of points with different properties such as their geometrical locations and the associated attributes (e.g., color, material properties, etc.). The number of the points within a point cloud can range from a thousand, to constitute simple 3D objects, up to billions, to realistically represent complex 3D scenes. Such huge amounts of data bring great technological challenges in terms of transmission, processing, and storage of point clouds.In recent years, numerous research works focused their efforts on the compression of meshes, while less was addressed for point clouds. We have identified two main approaches in the literature: a purely geometric one based on octree decomposition, and a hybrid one based on both geometry and video coding. The first approach can provide accurate 3D geometry information but contains weak temporal consistency. The second one can efficiently remove the temporal redundancy yet a decrease of geometrical precision can be observed after the projection. Thus, the tradeoff between compression efficiency and accurate prediction needs to be optimized.We focused on exploring the temporal correlations between dynamic dense point clouds. We proposed different approaches to improve the compression performance of the MPEG (Moving Picture Experts Group) V-PCC (Video-based Point Cloud Compression) test model, which provides state-of-the-art compression on dynamic dense point clouds.First, an octree-based adaptive segmentation is proposed to cluster the points with different motion amplitudes into 3D cubes. Then, motion estimation is applied to these cubes using affine transformation. Gains in terms of rate-distortion (RD) performance have been observed in sequences with relatively low motion amplitudes. However, the cost of building an octree for the dense point cloud remains expensive while the resulting octree structures contain poor temporal consistency for the sequences with higher motion amplitudes.An anatomical structure is then proposed to model the motion of the point clouds representing humanoids more inherently. With the help of 2D pose estimation tools, the motion is estimated from 14 anatomical segments using affine transformation.Moreover, we propose a novel solution for color prediction and discuss the residual coding from prediction. It is shown that instead of encoding redundant texture information, it is more valuable to code the residuals, which leads to a better RD performance.Although our contributions have improved the performances of the V-PCC test models, the temporal compression of dynamic point clouds remains a highly challenging task. Due to the limitations of the current acquisition technology, the acquired point clouds can be noisy in both geometry and attribute domains, which makes it challenging to achieve accurate motion estimation. In future studies, the technologies used for 3D meshes may be exploited and adapted to provide temporal-consistent connectivity information between dynamic 3D point clouds. Note de contenu :
Chapter 1 - Introduction
1.1. Background and motivation
1.2. Outline of the thesis and contributions
Chapter 2 - 3D Point Cloud Compression: State of the art
2.1. The 3D PCC “Universe Map” for methods
2.2. 1D methods: geometry traversal
2.3. 2D methods: Projection and mapping onto 2D planar domains
2.4. 3D methods: Direct exploitation of 3D correlations
2.5. DL-based methods
2.6. 3D PCC: What is missing?
2.7. MPEG 3D PCC standards
Chapter 3 - Extended Study of MPEG V-PCC and G-PCC Approaches
3.1. V-PCC methodology
3.2. Experimental evaluation of V-PCC
3.3. G-PCC methodology
3.4. Experimental evaluation of G-PCC
3.5. Experiments on the V-PCC inter-coding mode
3.6. Conclusion
Chapter 4 - Octree-based RDO segmentation
4.1. Pipeline
4.2. RDO-based octree segmentation
4.3. Prediction modeS
4.4. Experimental results
4.5. Conclusion
Chapter 5 - Skeleton-based motion estimation and compensation
5.1. Introduction
5.2. 3D Skeleton Generation
5.3. Motion estimation and compression
5.4. Experimental results
5.5. Conclusion
Chapter 6 - Temporal prediction using anatomical segmentation
6.1. Introduction
6.2. A novel dynamic 3D point cloud dataset
6.3. Prediction structure
6.4. Improved anatomy segmentation
6.5. Experimental results
6.6. Conclusion
Chapter 7 - A novel color compression for point clouds using affine transformation
7.1. Introduction
7.2. The residuals from both geometry and color
7.3. The prediction structure
7.4. Compression of the color residuals
7.5. Experimental results
7.6. Conclusion
Chapter 8 - Conclusion and future work
8.1. Conclusion
8.2. Future workNuméro de notice : 26821 Affiliation des auteurs : non IGN Thématique : IMAGERIE/INFORMATIQUE Nature : Thèse française Note de thèse : Thèse de Doctorat : informatique : Paris : 2021 Organisme de stage : Telecom SudParis nature-HAL : Thèse DOI : sans Date de publication en ligne : 13/04/2022 En ligne : https://tel.archives-ouvertes.fr/tel-03524521/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100476 Programmation d’un système de scannage multiple pilotable et mise en place de tests de qualité pour l’optimisation d’une chaîne de traitement photogrammétrique / Augustin Cosson (2021)
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PermalinkA generic framework for improving the geopositioning accuracy of multi-source optical and SAR imagery / Niangang Jiao in ISPRS Journal of photogrammetry and remote sensing, vol 169 (November 2020)
PermalinkApplication of 30-meter global digital elevation models for compensating rational polynomial coefficients biases / Amin Alizadeh Naeini in Geocarto international, vol 35 n° 12 ([01/09/2020])
PermalinkA regression model of spatial accuracy prediction for Openstreetmap buildings / Ibrahim Maidaneh Abdi in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, V-4 (August 2020)
PermalinkALERT: adversarial learning with expert regularization using Tikhonov operator for missing band reconstruction / Litu Rout in IEEE Transactions on geoscience and remote sensing, vol 58 n° 6 (June 2020)
PermalinkComparison and analysis of results of 3D modelling of complex cultural and historical objects using different types of terrestrial laser scanner / Admir Mulahusic in Survey review, vol 52 n° 371 (March 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)
PermalinkStatistical assessment of cartographic product from photogrammetry and fixed-wing UAV acquisition / Ademir Marques Junior in European journal of remote sensing, vol 53 n° 1 (2020)
PermalinkContribution à la segmentation et à la modélisation 3D du milieu urbain à partir de nuages de points / Tania Landes (2020)
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