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A K-Wishart Markov random field model for clustering of polarimetric SAR imagery
(Peer reviewed; Bokkapittel; Bok; Book; Chapter, 2011-10-20)
A clustering method that combines an advanced statistical distribution with spatial contextual information is proposed for multilook polarimetric synthetic aperture radar (PolSAR) data. It is based on a Markov random field (MRF) model that integrates a K-Wishart distribution for the PolSAR data statistics conditioned to each image cluster and a Potts model for the spatial context. Specifically, the ...
The Hotelling-Lawley trace statistic for change detection in polarimetric SAR data under the complex Wishart distribution
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014-01-27)
In this paper we propose a new test statistic for unsupervised changedetectioninpolarimetricsyntheticapertureradar(PolSAR) data. We work with multilook complex (MLC) covariance matrix data, whose underlying model is assumed to be the scaled complex Wishart distribution. We use the complex kind Hotelling-Lawley (HL) trace statistic for measuring the similarity of two covariance matrices. The sampling ...
Time Series Investigation of Land Subsidence Using a Weighted Least Squares Adjustment Based on Image Mode Interferometric Data
(Conference object; Konferansebidrag, 2010)
This study presents the weighted least squares method based on Interferometric Synthetic Aperture Radar (InSAR) images to retrieve spatial-temporal evolution of land subsidence in Mashhad Valley, northeast Iran. Using the analysis of a few interferograms covering the 2003-2005 period, Motagh et al (GJI 2006) presented a preliminary analysis of the subsidence in this area. Here we extend this study ...
A Textural–Contextual Model for Unsupervised Segmentation of Multipolarization Synthetic Aperture Radar Images
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
This paper proposes a novel unsupervised, non-Gaussian, and contextual segmentation method that combines an advanced statistical distribution with spatial contextual informa-tion for multilook polarimetric synthetic aperture radar (PolSAR)data. This extends on previous studies that have shown the added value of both non-Gaussian modeling and contextual smoothing individually or for intensity channels ...
Non-gaussian clustering of SAR images for glacier change detection
(Journal article; Tidsskriftartikkel, 2010-12)
Our aim is to use unsupervised, non-Gaussian clustering of Arctic glaciers for post-classification change detection. Firstly, we demonstrate the consistency of non-Gaussian clustering algorithms for Envisat ASAR images by characterizing the expected random error level for different SAR acquisition conditions (such as incidence angle). This allows us to determine whether an observed variation is ...
A change detector for polarimetric SAR data based on the relaxed Wishart distribution
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-12)
In this paper, we present an unsupervised change detection method for polarimetric synthetic aperture radar (PolSAR) images based on the relaxed Wishart distribution. Most polarimetric change detectors assume the Gaussian-based complex Wishart model for multilook covariance matrices, which is only satisfied for homogeneous areas with fully developed speckle and no texture. Liu et al. recently proposed ...
Estimation of atmospheric temperature and humidity profiles from MODIS data and radiosond data using artificial neural network
(Journal article; Tidsskriftartikkel; Peer reviewed, 2008)
The aim of this study is to test the quality of the neural network for retrieving the temperature and humidity by comparison with the radiosond values and a linear regression method. Remote sensed images give useful information about the atmosphere. In this article, MODIS data is used to retrieve temperature and humidity profiles of the atmosphere. Two methods of linear regression and artificial ...
Non-Gaussian Clustering of SAR images for Glacier Change Detection
(Conference object; Konferansebidrag, 2010)
Iceberg detection in open water and sea ice using C-band radar polarimetry
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-12-04)
Icebergs can cause a significant danger for shipping, offshore oil exploration, and undersea or subsea pipelines and production facilities. Synthetic aperture radar (SAR) is very valuable tool of detecting and monitoring icebergs in the often dark and cloud-covered polar regions. Detection of small icebergs floating in nonhomegeous sea clutter environments is a challenging task in remote sensing. ...
Polarimetric SAR Change Detection with the Complex Hotelling-Lawley Trace Statistic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-03-15)
In this paper, we propose a new test statistic for unsupervised change detection in polarimetric radar images. We work with multilook complex covariance matrix data, whose underlying model is assumed to be the scaled complex Wishart distribution. We use the complex-kind Hotelling-Lawley trace statistic for measuring the similarity of two covariance matrices. The distribution of the Hotelling-Lawley ...