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Auteur Joachim Niemeyer |
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Contextual classification of lidar data and building object detection in urban areas / Joachim Niemeyer in ISPRS Journal of photogrammetry and remote sensing, vol 87 (January 2014)
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Titre : Contextual classification of lidar data and building object detection in urban areas Type de document : Article/Communication Auteurs : Joachim Niemeyer, Auteur ; Franz Rottensteiner, Auteur ; Uwe Soergel, Auteur Année de publication : 2014 Article en page(s) : pp 152 - 165 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes descripteurs IGN] champ aléatoire de Markov
[Termes descripteurs IGN] classification contextuelle
[Termes descripteurs IGN] classification par forêts aléatoires
[Termes descripteurs IGN] détection du bâti
[Termes descripteurs IGN] données lidar
[Termes descripteurs IGN] données localisées 3D
[Termes descripteurs IGN] milieu urbain
[Termes descripteurs IGN] reconstruction 3D du bâtiRésumé : (Auteur) In this work we address the task of the contextual classification of an airborne LiDAR point cloud. For that purpose, we integrate a Random Forest classifier into a Conditional Random Field (CRF) framework. It is a flexible approach for obtaining a reliable classification result even in complex urban scenes. In this way, we benefit from the consideration of context on the one hand and from the opportunity to use a large amount of features on the other hand. Considering the interactions in our experiments increases the overall accuracy by 2%, though a larger improvement becomes apparent in the completeness and correctness of some of the seven classes discerned in our experiments. We compare the Random Forest approach to linear models for the computation of unary and pairwise potentials of the CRF, and investigate the relevance of different features for the LiDAR points as well as for the interaction of neighbouring points. In a second step, building objects are detected based on the classified point cloud. For that purpose, the CRF probabilities for the classes are plugged into a Markov Random Field as unary potentials, in which the pairwise potentials are based on a Potts model. The 2D binary building object masks are extracted and evaluated by the benchmark ISPRS Test Project on Urban Classification and 3D Building Reconstruction. The evaluation shows that the main buildings (larger than 50 m2) can be detected very reliably with a correctness larger than 96% and a completeness of 100%. Numéro de notice : A2014-017 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32922
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Code-barres Cote Support Localisation Section Disponibilité 081-2014011 RAB Revue Centre de documentation En réserve 3L Disponible Conditional random fields for urban scene : Classification with full waveform LiDAR Data / Joachim Niemeyer (2011)
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Titre : Conditional random fields for urban scene : Classification with full waveform LiDAR Data Type de document : Article/Communication Auteurs : Joachim Niemeyer, Auteur ; Jan Dirk Wegner, Auteur ; Clément Mallet , Auteur ; Franz Rottensteiner, Auteur ; Uwe Soergel, Auteur
Congrès : PIA 2011, ISPRS Conference on Photogrammetric Image Analysis (5 - 7 octobre 2011; Munich, Allemagne) , Commanditaire
Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2011 Importance : pp 233 - 244 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes descripteurs IGN] champ aléatoire conditionnel
[Termes descripteurs IGN] densité des points
[Termes descripteurs IGN] données lidar
[Termes descripteurs IGN] données localisées 3D
[Termes descripteurs IGN] forme d'onde pleine
[Termes descripteurs IGN] prise en compte du contexte
[Termes descripteurs IGN] zone urbaine denseRésumé : (auteur) We propose a context-based classification method for point clouds acquired by full waveform airborne laser scanners. As these devices provide a higher point density and additional information like echo width or type of return, an accurate distinction of several object classes is possible. However, especially in dense urban areas correct labelling is a challenging task. Therefore, we incorporate context knowledge by using Conditional Random Fields. Typical object structures are learned in a training step and improve the results of the point-based classification process. We validate our approach with two real-world datasets and by a comparison to Support Vector Machines and Markov Random Fields. Numéro de notice : C2011-033 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : IMAGERIE Nature : Communication En ligne : https://doi.org/10.1007/978-3-642-24393-6_20 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85946 Documents numériques
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