Title :
SAR image despeckling in directionlet domain based on edge detection
Author :
Sethunadh, R. ; Thomas, Tessamma
Author_Institution :
Indian Space Res. Organ. (ISRO), Trivandrum, India
Abstract :
Presented is a novel directionally adaptive despeckling algorithm for a SAR image using a multi-direction anisotropic wavelet transform, called a directionlet. It efficiently extracts edge information along dominant directions from the spatially segmented SAR image. Then an optimal scale dependent subband adaptive threshold, based on the generalised cross-validation technique, is applied to the edge removed image. The despeckled image is finally synthesised using the extracted edge information to preserve the sharpness of edges and the texture. The proposed scheme outperforms many of the traditional despeckling schemes such as the Lee filter and the wavelet and bandlet based edge detection methods in terms of numeric and perceptual quality.
Keywords :
edge detection; image segmentation; image texture; radar imaging; synthetic aperture radar; wavelet transforms; Lee filter; SAR image; bandlet base edge detection method; cross-validation technique; directionally adaptive despeckling algorithm; directionlet domain; edge sharpness; multidirection anisotropic wavelet transform; optimal scale dependent subband adaptive threshold; texture sharpness; wavelet base edge detection method;
Journal_Title :
Electronics Letters
DOI :
10.1049/el.2012.4533