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Speckle reduction in synthetic-aperture-radar imagery
Optics Letters
|September 22, 2009
Summary
Speckle noise in synthetic-aperture-radar (SAR) images obscures data. This study presents adapted local processing techniques to suppress speckle, improving image information content for better analysis.
Area of Science:
- Remote Sensing
- Image Processing
- Signal Processing
Background:
- Speckle noise in synthetic-aperture-radar (SAR) images degrades image quality and information content.
- Effective speckle suppression is crucial for accurate SAR image analysis.
Purpose of the Study:
- To investigate adapted local processing techniques for speckle noise suppression in SAR images.
- To evaluate two distinct processing algorithms for their effectiveness in reducing speckle.
Main Methods:
- Development of speckle noise suppression algorithms based on a statistical model accounting for multilook correlation.
- Application of two algorithms: one using image intensity, the other using a homomorphic transformation of intensity.
- Processing of Seasat-A SAR images to test the algorithms.
Main Results:
- Adapted local processing effectively suppresses speckle noise in SAR images.
- Both intensity-based and homomorphic transformation-based algorithms demonstrate speckle reduction capabilities.
- Processed images show improved definition of statistical parameters within local windows.
Conclusions:
- Local processing techniques offer a viable solution for mitigating speckle noise in SAR imagery.
- The developed algorithms enhance the utility of SAR data by improving image interpretability.
- Further experimental validation on Seasat-A data confirms the effectiveness of the proposed methods.
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