title: Rapid Urban Mapping Using SAR/Optical Imagery Synergy.
abstract: This paper highlights the potential of combining Synthetic Aperture Radar (SAR) and optical data for operational rapid urban mapping. An algorithm consisting of a completely unsupervised procedure for processing pairs of co-registered SAR/optical images is proposed. In a first stage, a texture analysis is conducted independently on the two images using eight different chain-based Gaussian models. In a second stage, the resulting texture images are partitioned by an unsupervised fuzzy K-means approach. Finally, a fuzzy decision rule is used to aggregate the results provided by the classification of texture images obtained from the pair of SAR and optical images. The method was tested and validated on images of Bucharest (Romania) and Cayenne (French Guiana). These two study areas are of different terrain relief, urban settlement structure and land cover complexity. The data set included Radarsat-1/ENVISAT and SPOT-4/5 images. The developed SAR/optical information fusion scheme improved the capabilities of urban areas extraction when compared with the separate use of SAR and optical sensors. It also proved to be suitable for monitoring urbanization development. The encouraging results thus confirm the potential of combining information from SAR and optical sensors for timely urban area analysis, as required in cases of disaster management and planning in urban sprawl areas.
authors.affiliation: ESPACE Unit, Institut de Recherche pour le Développement, Maison de la télédétection, 500 rue JF Breton, F34093 Montpellier cedex 5, France. christina.corbane@ird.fr.
authors.forename: Christina
authors.initials: C
authors.lastname: Corbane
authors.affiliation: ESPACE Unit, Institut de Recherche pour le Développement, Centre IRD de Cayenne, Route de Montabo, PO Box 165, F97323, Cayenne, French Guiana. jean-francois.faure@cayenne.ird.fr.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Faure
authors.affiliation: CEMAGREF, UMR TETIS, 500 rue François Breton, 34093 Montpellier cedex 5, France. baghdadi@teledetection.fr.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Baghdadi
authors.affiliation: ESPACE Unit, Institut de Recherche pour le Développement, Campus universitaire du Moufia, PO Box 172, 97492, Sainte-Clotilde, île de la Réunion. nicolas.villeneuve@ird.fr.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Villeneuve
authors.affiliation: ESPACE Unit, Institut de Recherche pour le Développement, Maison de la télédétection, 500 rue JF Breton, F34093 Montpellier cedex 5, France. michel.petit@ird.fr.
authors.forename: Michel
authors.initials: M
authors.lastname: Petit
keywords: SAR sensors; fuzzy K-means classification; information fusion; optical sensors; rapid urban mapping; texture analysis