SAR amplitude filtering using TV prior and its application to building delineation
Abstract
This paper investigates the use of a popular regularization model, the Total Variation minimization (TV), to filter SAR images and reduce speckle noise. This model is extensively used for its property of preserving edges. Due to the many local minima, TV minimization is difficult to achieve for non-convex likelihood terms such as that of SAR amplitude. Such a minimization can be performed efficiently by computing minimum cuts on weighted graphs. Exact minimization, although theoretically possible, can not be implemented due to memory constraints on large images required by remote sensing applications. The computational burden of the state-of-the-art algorithm for approximate minimization is also heavy. In this paper, we propose a new fast approximate discrete algorithm. The filtering is applied in the framework of building delineation for 3D reconstruction. Results on real images are presented.