SAR images are generally corrupted by speckle noise. To suppress speckle and improve the radar image analysis lots of filtering techniques have been proposed. The module implements to well-known despeckle methods: Frost, Lee, Gamma-MAP and Kuan.
Figure (?? shows an extract of a SLC Sentinel1 image, band VV, taken over Cape Verde and the result of the Gamma filter. The following commands were used to produce the despeckled extract :
First, the original image is converted into an intensity one (real part corresponds to band 1, and imaginary part to band 2):
Then the intensity image is despeckled with the Gamma-MAP filter :
The produced images were then rescaled to intensities ranging from 0 to 255 in order to be displayed.