Abstract
A case study of removing speckle noises by using a method proposed by Jong-Sen Lee et al. in 1999 which preserved the edges of polarimetric SAR images through a filter. This study took place in Tomakomai, Japan. Two JPL/AIRSAR L and C band polarimetric mode SAR images were used to evaluate the filter effect. In the image mainly consisted mountain area, even after averaged 45 pixels by 9 × 9 nonsquare window size of filter, the geographical features and edge sharpness were preserved without degrading image quality. In the other image mainly consisted forest area, the effect of suppressed speckle noise was recognized and the optimum size of filter was selected with the 7 × 7 window for forest classification. The result of this case study shows that the Lee's filter to preserve edge polarimetric SAR images is the best available method to suppress the speckle noise without crosstalk, and preserved edge sharpness and preserved polarimetric properties. This study indicates that the effect of the Lee's filter with 9 × 9 window is better than the moving average filter with 5 × 5 window. The filtered effect is excellent to suppress the speckle noise due to intensity, but is not sufficient to suppress the speckle noise due to phase differences.
