Speckle Reduction of Synthetic Aperture Radar Images using Median Filter and Savitzky-Golay Filter

International Journal of Computer Applications
© 2015 by IJCA Journal
Volume 113 - Number 11
Year of Publication: 2015
Ruchita Gir
Lalit Jain
Rajesh Rai

Ruchita Gir, Lalit Jain and Rajesh Rai. Article: Speckle Reduction of Synthetic Aperture Radar Images using Median Filter and Savitzky-Golay Filter. International Journal of Computer Applications 113(11):38-43, March 2015. Full text available. BibTeX

	author = {Ruchita Gir and Lalit Jain and Rajesh Rai},
	title = {Article: Speckle Reduction of Synthetic Aperture Radar Images using Median Filter and Savitzky-Golay Filter},
	journal = {International Journal of Computer Applications},
	year = {2015},
	volume = {113},
	number = {11},
	pages = {38-43},
	month = {March},
	note = {Full text available}


SAR images are corrupted by speckle noise which is based on multiplicative noise or Reyleigh noise. The speckle degrades the quality of image and makes interpretations, analysis and classifications of SAR images harder. Therefore some speckle mitigation is necessary prior to the processing of SAR images. In this paper a new method is proposed for despeckling of SAR images in which Savitzky-Golay filter and median filter are used for denoising of the synthetic aperature radar (SAR) image. After obtaining filtered image they are decomposed by the use of undecimated wavelet transform. The speckled input image is also decomposed using undecimated wavelet transform. Then image segmentation is done by the use of brute force thresholding wavelet based algorithm in which each pixel of the entire decomposed image is compared and the maximum value of threshold image pixel is replaced in every iteration of image processing. Lastly enhanced directional smoothing of the image is done to obtain a despeckled image


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