Speckle Noise Filtering for Sea SAR Image

The aliasing of the speckle noise and echo information of sea SAR blurs the structure character of sea SAR image. It is difficult that to enhance structure character of sea SAR image. Aiming at this difficulty, we propose a amalgamation frame based on EMD and exponent. The frame can effectively filter the speckle noise and enhance the structure character which finally can be seen by people’s eyes. Using the different frequency character of each level, the content of each level noise and non-noise are analyzed and exponent of each level is adjusted. And the speckle noise of simple SAR image in different scale is filtered. At last, we obtain the new denoised SAR image. The experiment result indicates that speckle noise of our result is substantially decreased and the structure character and texture of the result is clearer. And ours eyes can distinguish the character of sea SAR image. So that it proves that our filtering algorithm is effective to filter the speckle noise of sea SAR image.

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