s1tbx Speckle Filter Lee Sigma

I want use snap to pre-processing sentinel-1 data about oil spill. And I find ‘Lee Sigma’ is more popular in SAR speckle filter. When I set the parameters, I don’t know what is ‘Window Size’ and ‘Target Window Size’. I want to know what they stand for. I would appreciate it even more if there were additional explanations for the other parameters.
This is my first time to use snap, so… Please HELP…
Thank you.

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the parameters are explained in the official articles which published these filters, they are listed here: Speckle filtering with Lee filters

More general, the window size determines how much of the surrounding pixels of a center pixel are taken into account when estimating the local statistics. Some filters have two window sizes and combine statistics (mean, standard deviation) of them to decide how strong to apply the filtering for each individual pixel.

In the Lee Sigma filter, not all pixels are filtered. Instead, point targets (i.e. point strong scatterers) are detected and preserved. The target window is used for point target detection. If the center pixel value is above a preset threshold and a certain percent of the other pixels in the same target window are also above the threshold, then these pixels are considered as point target pixels and their values are preserved directly without filtering. “Target Window Size” is the dimension of the target window.

The “window Size” is the dimension of the sliding window used in computing local statistics as @ABraun has explained above.

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Ok, I understand. Thank you for your reply and help.