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Auteur M. Liao |
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Satellite SAR geocoding with refined RPC model / L. Zhang in ISPRS Journal of photogrammetry and remote sensing, vol 69 (April 2012)
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Titre : Satellite SAR geocoding with refined RPC model Type de document : Article/Communication Auteurs : L. Zhang, Auteur ; Timo Balz, Auteur ; M. Liao, Auteur Année de publication : 2012 Article en page(s) : pp 37 - 49 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] appariement d'images
[Termes IGN] erreur corrélée au temps
[Termes IGN] géoréférencement indirect
[Termes IGN] image radar moirée
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle par fonctions rationnelles
[Termes IGN] propagation du signalRésumé : (Auteur) Recent studies have proved that the Rational Polynomial Camera (RPC) model is able to act as a reliable replacement of the rigorous Range-Doppler (RD) model for the geometric processing of satellite SAR datasets. But its capability in absolute geolocation of SAR images has not been evaluated quantitatively. Therefore, in this article the problems of error analysis and refinement of SAR RPC model are primarily investigated to improve the absolute accuracy of SAR geolocation. Range propagation delay and azimuth timing error are identified as two major error sources for SAR geolocation. An approach based on SAR image simulation and real-to-simulated image matching is developed to estimate and correct these two errors. Afterwards a refined RPC model can be built from the error-corrected RD model and then used in satellite SAR geocoding. Three experiments with different settings are designed and conducted to comprehensively evaluate the accuracies of SAR geolocation with both ordinary and refined RPC models. All the experimental results demonstrate that with RPC model refinement the absolute location accuracies of geocoded SAR images can be improved significantly, particularly in Easting direction. In another experiment the computation efficiencies of SAR geocoding with both RD and RPC models are compared quantitatively. The results show that by using the RPC model such efficiency can be remarkably improved by at least 16 times. In addition the problem of DEM data selection for SAR image simulation in RPC model refinement is studied by a comparative experiment. The results reveal that the best choice should be using the proper DEM datasets of spatial resolution comparable to that of the SAR images. Numéro de notice : A2012-193 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2012.02.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2012.02.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31640
in ISPRS Journal of photogrammetry and remote sensing > vol 69 (April 2012) . - pp 37 - 49[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-2012031 SL Revue Centre de documentation Revues en salle Disponible Urban change detection based on coherence and intensity characteristics of SAR imagery / M. Liao in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 8 (August 2008)
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Titre : Urban change detection based on coherence and intensity characteristics of SAR imagery Type de document : Article/Communication Auteurs : M. Liao, Auteur ; L. Jiang, Auteur ; H. Lin, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 999 - 1006 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] analyse diachronique
[Termes IGN] cohérence (physique)
[Termes IGN] croissance urbaine
[Termes IGN] détection de changement
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] image ERS-SAR
[Termes IGN] image multitemporelle
[Termes IGN] image radar moirée
[Termes IGN] intensité lumineuse
[Termes IGN] radargrammétrie
[Termes IGN] seuillage d'image
[Termes IGN] Shanghai (Chine)Résumé : (Auteur) In this paper, an unsupervised change-detection approach was proposed to detect new urban areas from multi-temporal SAR images. The novelty of the proposed approach is the joint use of coherence and intensity characteristics of SAR imagery. The approach involves two main steps: (a) the extraction of difference feature containing information on changed areas, and (b) the unsupervised two-dimensional (2D) thresholding. First, two difference features based on the concepts of long-term coherence and backscattering temporal variability are extracted from a series of multitemporal SAR images. Then, the resulting features that represent the INSAR signal temporal variability of changed areas are merged, and a 2D thresholding technique based on the maximum 2D Renyi’s entropy criterion is developed to obtain the change-detection results. The effectiveness of the proposed approach is confirmed with experimental results obtained from a set of six ERS-1/2 SLC SAR images acquired in Shanghai, China. Copyright ASPRS Numéro de notice : A2008-329 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.74.8.999 En ligne : https://doi.org/10.14358/PERS.74.8.999 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29322
in Photogrammetric Engineering & Remote Sensing, PERS > vol 74 n° 8 (August 2008) . - pp 999 - 1006[article]