Displacement Estimation by Maximum Likelihood Texture Tracking

International audienceThis paper presents a novel method to estimate displacement by maximum-likelihood (ML) texture tracking. The observed polarimetric synthetic aperture radar (PolSAR) data-set is composed by two terms: the scalar texture parameter and the speckle component. Based on the Spherically Invariant Random Vectors (SIRV) theory, the ML estimator of the texture is computed. A generalization of the ML texture tracking based on the Fisher probability density function (pdf) modeling is introduced. For random variables with Fisher distributions, the ratio distribution is established. The proposed method is tested with both simulated PolSAR data and spaceborne PolSAR images provided by the TerraSAR-X (TSX) and the RADARSAT-2 (RS-2) sensors

Maximum Likelihood Shift Estimation using High Resolution Polarimetric SAR Clutter Model

International audienceThis paper deals with a Maximum Likelihood (ML) shift estimation method in the context of High Resolution (HR) Polarimetric SAR (PolSAR) clutter. Texture modeling is exposed and the generalized ML texture tracking method is extended to the merging of various sensors. Some results on displacement estimation on the Argentiere glacier in the Mont Blanc massif using dual-pol TerraSAR-X (TSX) and quad-pol RADARSAT-2 (RS2) sensors are finally discussed

Segmentation and Classification of Polarimetric SAR Data based on the KummerU Distribution

International audienceThinner spatial features can be observed from the high resolution of newly available spaceborne and airborne SAR images. Heterogeneous clutter models should be used to model the covariance matrix because each resolution cell contains only a small number of scatterers. In this paper, we focus on the use of a Fisher probability density function (pdf) to model the SAR clutter. First, the benefit of using such a pdf is exposed. Covariance matrix statistics are then analyzed in details. For a Fisher distributed texture, the covariance matrix follows a KummerU pdf. Asymptotic cases of this pdf are presented. Finally, the KummerU pdf is implemented in both hierarchical segmentation and classification algorithms. Segmentation and classification results are shown on both synthetic and real data

Segmentation and Classification of Polarimetric SAR Data based on the KummerU Distribution

International audienceThinner spatial features can be observed from the high resolution of newly available spaceborne and airborne SAR images. Heterogeneous clutter models should be used to model the covariance matrix because each resolution cell contains only a small number of scatterers. In this paper, we focus on the use of a Fisher probability density function (pdf) to model the SAR clutter. First, the benefit of using such a pdf is exposed. Covariance matrix statistics are then analyzed in details. For a Fisher distributed texture, the covariance matrix follows a KummerU pdf. Asymptotic cases of this pdf are presented. Finally, the KummerU pdf is implemented in both hierarchical segmentation and classification algorithms. Segmentation and classification results are shown on both synthetic and real data

Using Quad‐Pol and Single‐Pol RADARSAT‐2 Data for Monitoring Cold Alpine and Outlet Antarctic Glaciers

International audienceThis paper presents some applications of the Maximum Likelihood (ML) texture tracking on displacement estimation of some alpine and antarctic glaciers surfaces. This method is adapted to the statistical characteristic of the new High Resolution (HR) Polarimetric SAR (Pol- SAR) data. The ML texture tracking method is firstly reminded and a statistical model of HR PolSAR data is explained. The main part of this paper is focused on the application of this method on glaciers monitoring. Three different glaciers have been chosen to test the algorithm: a cold alpine glacier, a temperate alpine glacier and an outlet antarctic glacier. The accuracy and limits of the method are highlighted in each case and results application is discussed

A first comparison of Cosmo-Skymed and TerraSAR-X data over Chamonix Mont-Blanc test-site

International audienceThis paper presents the first results obtained with satellite im- age time series (SITS) acquired by Cosmo-SkyMed (CSK) over the Chamonix Mont-Blanc test-site. A CSK SITS made of 39 images is merged with a TerraSAR-X SITS made of 26 images by using the orbital information and co-registration tools developed in the EFIDIR project. The results are illus- trated by the computation of speckle-free images by temporal averaging, by the generation and comparison of topographic interferograms and by the measure of glacier displacement fields by amplitude correlation

Monitoring temperate glaciers: combined use of multi-date TerraSAR-X images and continous GPS measurements

International audienceThis paper highlights the contribution of TerraSAR-X (TSX) High Resolution (HR) images for temperate glacier monitoring. A series of 14 images have been acquired since October 2007 on the Mont-Blanc test area. This area involves well-known temperate glaciers which have been monitored and instrumented ("stick" for annual displacement/ablation, GPS, cavitometer for basal displacement...) for more than 50 years. The combined use of in-situ measurements and multi-temporal images allows to improve the potential of HR SAR measurements. Interpretation of HR images, investigation of interferometric and correlation methods, and the first glacier displacement results are presented

Méthodes statistiques en télédétection RSO polarimétrique haute résolution pour la modélisation et le suivi temporel des glaciers.

This work introduces a general method for glaciers surface displacement estimation using High Resolution PolSAR images. With high resolution details, the texture tracking methods become useful and complementary to the classical differential interferometry methods which are difficult to implement in this context. The proposed method is based on the multivariate SAR images ratio likelihood. The use of the ratio and corresponding statistic distributions is well adapted to the multiplicative noise of such images. The extracted texture component from HR PolSAR data according to SIRV model is less sensitive to the variations of the snow surface than the classical intensity. The statistical modeling of such component is discussed and the benefit of Fisher modeling is highlighted. Some tests have been performed to analyze the behavior of various similarity criteria. The methodology is finally completed with advanced processing like hierarchical segmentation and the use of a flow model. Two test sites in French Alps with the Argentière glacier and in Antarctica with the Astrolabe glacier have been used to validate the proposed method. A preliminary study on sensor merging for displacement estimation is finally introduced.Ce travail de thèse propose une méthode générale d'estimation de déplacement de la surface des glaciers à partir d'images RSO polarimétriques à Haute Résolution spatiale. Les caractéristiques nouvelles de ces images offrent un niveau de détail propice au développement de nouvelles méthodes de suivi de texture complémentaires aux méthodes classiques d'interférométrie RADAR difficiles à mettre en oeuvre dans ce contexte. La méthode proposée est basée sur la vraisemblance du rapport d'images RSO multivariées. L'utilisation du rapport d'images RSO et des lois statistiques correspondantes offrent une souplesse adaptée aux caractéristiques des images RSO notamment au caractère multiplicatif du chatoiement. La texture extraite du jeu polarimétrique offre une bonne robustesse aux variations surfaciques de la neige. La question du modèle statistique sous-jacent des images HR est abordé et l'utilisation des lois de Fisher est justifié. Des protocoles de test permettent de souligner la sensibilité de ce type de méthode. Le schéma méthodologique est complété par un ensemble de traitements avancés tels que la segmentation hiérarchique et l'utilisation d'un modèle d'écoulement. Deux sites d'études dans les Alpes françaises et en Antarctique ont permis d'éprouver cette méthode sur l'estimation de déplacement des glaciers d'Argentière et de l'Astrolabe. Une étude préliminaire sur la généralisation multi-capteurs de cette chaîne de traitement est finalement introduite

Suivi de texture par le Maximum de Vraisemblance dans les images RSO Polarimétriques Haute Résolution

National audienceLa haute résolution spatiale (HR) offerte par les capteurs Radar a' Synthèse d'Ouverture (RSO) ouvre de nouvelles perspectives quant aux méthodes de mesures de déplacement. Ce papier présente et généralise une méthode d'estimation de déplacement basé sur un suivi de texture dans les images RSO polarimétriques HR. Après avoir souligne ́ la pertinence de la loi de Fisher pour la modélisation de ces données, un critère de similarité est utilise ́ pour montrer quelques résultats sur le déplacement de surface du glacier d'Argentière dans le massif du Mont Blan

Méthodes statistiques en télédétection RSO polarimétrique haute résolution pour la modélisation et le suivi temporel des glaciers

Ce travail de thèse propose une méthode générale d'estimation de déplacement de la surface des glaciers à partir d'images RSO polarimétriques à Haute Résolution spatiale. Les caractéristiques nouvelles de ces images offrent un niveau de détail propice au développement de nouvelles méthodes de suivi de texture complémentaires aux méthodes classiques d'interférométrie RADAR difficiles à mettre en œuvre dans ce contexte. La méthode proposée est basée sur la vraisemblance du rapport d'images RSO multivariées. L'utilisation du rapport d'images RSO et des lois statistiques correspondantes offrent une souplesse adaptée aux caractéristiques des images RSO notamment au caractère multiplicatif du chatoiement. La texture extraite du jeu polarimétrique offre une bonne robustesse aux variations surfaciques de la neige. La question du modèle statistique sous-jacent des images HR est abordé et l'utilisation des lois de Fisher est justifié. Des protocoles de test permettent de souligner la sensibilité de ce type de méthode. Le schéma méthodologique est complété par un ensemble de traitements avancés tels que la segmentation hiérarchique et l'utilisation d'un modèle d'écoulement. Deux sites d'études dans les Alpes françaises et en Antarctique ont permis d'éprouver cette méthode sur l'estimation de déplacement des glaciers d'Argentière et de l'Astrolabe. Une étude préliminaire sur la généralisation multi-capteurs de cette chaîne de traitement est finalement introduite.This work introduces a general method for glaciers surface displacement estimation using High Resolution PolSAR images. With high resolution details, the texture tracking methods become useful and complementary to the classical differential interferometry methods which are difficult to implement in this context. The proposed method is based on the multivariate SAR images ratio likelihood. The use of the ratio and corresponding statistic distributions is well adapted to the multiplicative noise of such images. The extracted texture component from HR PolSAR data according to SIRV model is less sensitive to the variations of the snow surface than the classical intensity. The statistical modeling of such component is discussed and the benet of Fisher modeling is highlighted. Some tests have been performed to analyze the behavior of various similarity criteria. The methodology is finally completed with advanced processing like hierarchical segmentation and the use of a flow model. Two test sites in French Alps with the Argentiere glacier and in Antarctica with the Astrolabe glacier have been used to validate the proposed method. A preliminary study on sensor merging for displacement estimation is finally introduced.RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF