Title :
A Novel Sparse Method for Despeckling SAR Images
Author :
Amirmazlaghani, Maryam ; Amindavar, Hamidreza
Author_Institution :
Dept. of Comput. Eng. & Inf. Technol., Amirkabir Univ. of Technol., Tehran, Iran
Abstract :
This paper presents an algorithm for speckle reduction of synthetic aperture radar (SAR) images within a framework of multiscale curvelet analysis. First, we introduce a novel method to investigate the presence of 2-D heteroscedasticity based on Lagrange multiplier procedure. Employing this test confirms the heteroscedasticity of SAR image curvelet coefficients. Therefore, we employ a generalization of 2-D generalized autoregressive conditional heteroscedastic (2-D GARCH) model, called 2-D GARCH generalized Gaussian (2-D GARCH-GG), to these coefficients. This model preserves the appropriate properties of 2-D GARCH for modeling the curvelet coefficients while extending the dynamic formulation of 2-D GARCH model. Then, we design a novel Bayesian processor based on employing 2-D GARCH-GG model to estimate the noise-free curvelet coefficients. Experiments carried out on synthetic SAR images, as well as on true SAR images, verify the performance improvement in utilizing the new strategy compared with other established despeckle algorithms.
Keywords :
curvelet transforms; geophysical image processing; remote sensing by radar; speckle; synthetic aperture radar; 2D GARCH generalized Gaussian; 2D GARCH-GG; 2D generalized autoregressive conditional heteroscedastic; 2D heteroscedasticity model; Bayesian processor; Lagrange multiplier procedure; SAR image despeckling; multiscale curvelet analysis; sparse method; speckle reduction; synthetic aperture radar; Gaussian distribution; Lagrangian functions; Maximum a posteriori estimation; Noise measurement; Noise reduction; Speckle; Synthetic aperture radar; 2-D GARCH-GG model; Curvelet transform; Lagrange mutiplier; maximum a posteriori (MAP) estimation; synthetic aperture radar (SAR);
Journal_Title :
Geoscience and Remote Sensing, IEEE Transactions on
DOI :
10.1109/TGRS.2012.2195321