Risk based parameter selection for polarimetric SAR speckle reduction

In this paper, we introduce an automatic parameter selection technique for the polarimetric bilateral filter. The method is inspired by the theory of unbiased risk estimation that allows to compare different estimators with respect to a loss function. Moreover, a local risk estimation allows spatially varying parameters. We demonstrate our approach on experimental data and show how the method improves the smoothing capabilities of the filter in homogeneous areas while retaining its edge preserving properties.