Centre de documentation
scientifique

Dépouillements

Integrating user needs on misclassification error sensitivity into image segmentation quality assessment / Hugo Costa in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 6 (June 2015)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 6 (June 2015) . - pp 451 - 459 Titre : Integrating user needs on misclassification error sensitivity into image segmentation quality assessment Type de document : Article/Communication Auteurs : Hugo Costa, Auteur ; Giles M. Foody, Auteur ; Doreen S. Boyd, Auteur Année de publication : 2015 Article en page(s) : pp 451 - 459 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] analyse des besoins [Termes IGN] classification dirigée [Termes IGN] connaissance thématique [Termes IGN] objet géographique [Termes IGN] occupation du sol [Termes IGN] segmentation d'image [Termes IGN] similitude [Termes IGN] utilisateur Résumé : (auteur) Commonly the assessment of the quality of image segmentations used in object-based land cover classification uses the geometric match between the derived segmentation and a reference dataset. This paper argues that a more appropriate assessment of a segmentation is to also consider the thematic content of the objects generated. This allows the assessment to be tailored to the needs of the specific user. A new method for image segmentation quality assessment is described, which combines a traditional geometric-only method with the thematic similarity index (TSI), a metric that expresses the degree of thematic quality of objects from a user’s perspective. The perspectives of two users (a wolf researcher and a general user of land cover information) were adopted in a case study to demonstrate the new method. The results show that the new method allowed the production of more accurate land cover classifications for the two users than the use of the geometric-only approach Numéro de notice : A2015-976 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.6.451 En ligne : https://doi.org/10.14358/PERS.81.6.451 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80059 [article]

Mangrove tree crown delineation from high-resolution imagery / Muditha K. Heenkenda in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 6 (June 2015)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 6 (June 2015) . - pp 471 - 479 Titre : Mangrove tree crown delineation from high-resolution imagery Type de document : Article/Communication Auteurs : Muditha K. Heenkenda, Auteur ; Karen E. Joyce, Auteur ; Stefan W. Maier, Auteur Année de publication : 2015 Article en page(s) : pp 471 - 479 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] analyse d'image orientée objet [Termes IGN] croissance des arbres [Termes IGN] houppier [Termes IGN] image à haute résolution [Termes IGN] image Worldview [Termes IGN] mangrove [Termes IGN] modèle numérique de surface [Termes IGN] objet géographique Résumé : (auteur) Mangroves are very dense, spatially heterogeneous, and have limited height variations between neighboring trees. Delineating individual tree crowns is thus very challenging. This study compared methods for isolating mangrove crowns using object based image analysis. A combination of WorldView-2 imagery, a digital surface model, a local maximum filtering technique, and a region growing approach achieved 92 percent overall accuracy in extracting tree crowns. The more traditionally used inverse watershed segmentation method showed low accuracy (35 percent), demonstrating that this method is better suited to homogeneous forests with reasonable height variations between trees. The main challenges with each of the methods tested were the limited height variation between surrounding trees and multiple upward pointing branches of trees. In summary, mangrove tree crowns can be delineated from appropriately parameterized objectbased algorithms with a combination of high-resolution satellite images and a digital surface model. We recommend partitioning the imagery into homogeneous species stands for best results. Numéro de notice : A2015-977 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.81.6.471 En ligne : https://doi.org/10.14358/PERS.81.6.471 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80060 [article]

Object-based building change detection from a single multispectral image and pre-existing geospatial information / Georgia Doxani in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 6 (June 2015)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 6 (June 2015) . - pp 481 - 489 Titre : Object-based building change detection from a single multispectral image and pre-existing geospatial information Type de document : Article/Communication Auteurs : Georgia Doxani, Auteur ; Konstantinos Karantzalos, Auteur ; Maria Tsakiri-Strati, Auteur Année de publication : 2015 Article en page(s) : pp 481 - 489 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] analyse d'image orientée objet [Termes IGN] analyse de l'existant [Termes IGN] analyse diachronique [Termes IGN] base de données localisées [Termes IGN] bâtiment [Termes IGN] classification à base de connaissances [Termes IGN] détection de changement [Termes IGN] Grèce [Termes IGN] image isolée [Termes IGN] image multibande [Termes IGN] milieu urbain Résumé : (auteur) Multispectral images of very high spatial resolution and vector data from geospatial databases, such as cadastral maps, are among the cost-effective and broadly available geodata in urban environments. Therefore, we aim to address building change detection based on pre-existing building footprint information and a single very high resolution multispectral image. An object-based classification methodology was developed that employs advanced scalespace filtering, unsupervised clustering, and knowledge-based classification. The developed framework effectively integrates prior vector data and multispectral observations, through incorporating the prior knowledge into the training process and defining the proper object-based classification rules. The methodology successfully identified important building changes, which were validated by employing the vector information of a building geodatabase and a QuickBird image acquired in 2003 and 2007, respectively, over urban regions in the city of Thessaloniki, Greece. The performed quantitative and qualitative evaluation indicated that the proposed analysis framework can detect the new buildings with high accuracy rates and, to a lesser degree, their exact shape and size. Numéro de notice : A2015-978 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.6.481 En ligne : https://doi.org/10.14358/PERS.81.6.481 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80061 [article]

A fuzzy spatial reasoner for multi-scale GEOBIA ontologies / Argyros Argyridis in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 6 (June 2015)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 6 (June 2015) . - pp 491 - 498 Titre : A fuzzy spatial reasoner for multi-scale GEOBIA ontologies Type de document : Article/Communication Auteurs : Argyros Argyridis, Auteur ; Demetre P. Argialas, Auteur Année de publication : 2015 Article en page(s) : pp 491 - 498 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] analyse d'image orientée objet [Termes IGN] classification à base de connaissances [Termes IGN] détection du bâti [Termes IGN] image Quickbird [Termes IGN] objet géographique [Termes IGN] ontologie [Termes IGN] OWL [Termes IGN] PostgreSQL [Termes IGN] segmentation d'image [Termes IGN] toit Résumé : (auteur) In Geographic Object-Based Image Analysis (GEOBIA), an image is partitioned into objects by a segmentation algorithm. These objects are then classified into semantic categories based on unsupervised/ supervised methods, or knowledge-based methods, such as an ontology. The aim of this paper was to develop a SPatial Ontology Reasoner (SPOR) to allow the development of GEOBIA ontologies by employing fuzzy, spatial, and multi-scale representations, with time efficiency. An enhanced version of the Web Ontology Language 2 (OWL 2) with fuzzy representations was adopted and expanded to represent fuzzy spatial relationships within the framework of GEOBIA. Segmentation results are stored within PostgreSQL. An ontology described the class/subclass hierarchy and class definitions. SPOR integrated PostgreSQL and the ontology, to classify the objects. To demonstrate the framework, a QuickBird image was employed for building extraction. Accuracy assessment indicated that 87 percent of building rooftops were detected. Numéro de notice : A2015-979 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.6.491 En ligne : https://doi.org/10.14358/PERS.81.6.491 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80062 [article]

Assessment of wildfire risk in Lebanon using geographic object-based image analysis / George Mitri in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 6 (June 2015)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 6 (June 2015) . - pp 499 - 506 Titre : Assessment of wildfire risk in Lebanon using geographic object-based image analysis Type de document : Article/Communication Auteurs : George Mitri, Auteur ; Mireille Jazi, Auteur ; David McWethy, Auteur Année de publication : 2015 Article en page(s) : pp 499 - 506 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] analyse d'image orientée objet [Termes IGN] biomasse (combustible) [Termes IGN] carte thématique [Termes IGN] incendie de forêt [Termes IGN] Liban [Termes IGN] objet géographique [Termes IGN] prévention des risques [Termes IGN] risque naturel [Termes IGN] vulnérabilité Résumé : (auteur) During the past decade, Lebanon has experienced a large number of severe wildfires that have had significant social and ecological consequences. In this context, the assessment of wildfire risk is important to support planning of fire prevention measures and risk mitigation. The purpose of this study was to assess the spatial distribution of wildfire risk in Lebanon. The objectives were to identify and map (a) wildfire hazard, (b)wildfire vulnerability, and (c) wildfire risk. We developed a model using geospatial biophysical and climatic data and Geographic Object-Based Image Analysis (GEOBIA). Development of the wildfire hazard map included classification of forest fuel type, combustibility, and fire spread whereas the vulnerability map included classification of demographic vulnerability (i.e., boundary, occupation and scatter indicators) and forest vulnerability (i.e., environmental and replacement values). The resulting geospatial map of wildfire risk provided important information for potential use in fire risk management. Numéro de notice : A2015-980 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.6.499 En ligne : https://doi.org/10.14358/PERS.81.6.499 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80063 [article]