A review of SAR speckle filters: texture restoration and preservation

Speckle filtering is probably one of the important steps in post SAR (synthetic aperture radar) image processing. Speckle appears in all SAR products including single-polarimetric, multipolarimetric and interferometric image data. Many speckle filtering algorithms have been proposed aimed at speckle reduction. Texture, revealing the spatial-dependent information in images, may be as important as other polarimetric measures. Such information is not expected being distorted and degraded during speckle suppression. This paper examines various speckle filters including the Lee, Frost, Kuan and other filters in terms of texture preservation. The first and second order texture measures are used in the assessment