Title :
Parametric modeling of the fractional Fourier transform coefficients for complex-valued SAR image categorization
Author :
Singh, Jaskirat ; Datcu, Mihai
Author_Institution :
Remote Sensing Technol. Inst. (IMF), German Aerosp. Center (DLR), Oberpfaffenhofen, Germany
Abstract :
In high-resolution (HR) and very-high resolution (VHR) synthetic aperture radar (SAR) images, focus is now on the patch-oriented image categorization in contrast to the pixel-based classification in low-resolution SAR images. SAR image categorization requires the generation of a compact feature descriptor that accurately defines the content of the image patch under consideration. In this paper we propose a parametric feature descriptor generated on the complex-valued SAR image within a transformation space. The fractional Fourier transform (FrFT), has been considered to transform the image pixels of the single-look complex (SLC) SAR images in order to obtain a simpler statistical response. The real and imaginary components of the complex-valued FrFT coefficients have been modelled with generalized Gaussian distribution (GGD). The proposed feature descriptor is compared with a Wavelet-decomposition-based parametric feature descriptor; and with the FrFT-based and Gabor-filter-bank-based non-parametric feature descriptors. Categorization accuracy enhancement is demonstrated over several categories comprising of natural topologies. The experimental database consists of 2000 image patches (of size 200 × 200 pixels) extracted from SLC HR TerraSAR-X scenes.
Keywords :
Fourier transforms; Gabor filters; Gaussian distribution; channel bank filters; feature extraction; image classification; image resolution; radar imaging; radar resolution; synthetic aperture radar; wavelet transforms; FrFT-based nonparametric feature descriptors; GGD; Gabor-filter-bank-based nonparametric feature descriptors; SLC SAR images; VHR synthetic aperture radar images; categorization accuracy enhancement; compact feature descriptor; complex-valued FrFT coefficients; complex-valued SAR image categorization; fractional Fourier transform coefficients; generalized Gaussian distribution; image patch; image pixels; low-resolution SAR images; natural topologies; parametric modeling; patch-oriented image categorization; pixel-based classification; single-look complex SAR images; statistical response; transformation space; very-high resolution synthetic aperture radar images; wavelet-decomposition-based parametric feature descriptor; Feature descriptor; generalized Gaussian distribution (GGD); synthetic aperture radar (SAR); the fractional Fourier transform (FrFT);
Conference_Titel :
Image Processing (ICIP), 2013 20th IEEE International Conference on
Conference_Location :
Melbourne, VIC
DOI :
10.1109/ICIP.2013.6738593