SAR Image Speckle Reduction Based On Direction Information

SAR(Synthetic Aperture Radar, SAR) is a high-resolution imaging radar, with all-weather, all-time imaging capabilities, and could carry out polarization measurement and interference measurement, to get infromation about the backward scattering properties of the back surface, high-precision Three-dimensional terrain and small deformation. Therefore, since the90s of the20th century SAR technology has been rapid developed and been widely used in various fields. However, because of the defects of the SAR imaging principle, the process will produce speckle noise. So in SAR image processing, it’s the first step to remove speckle noise of the image.In order to achieve the goal of removing the noise and maintaining the edges and details of the image, many algorithms have been proposed, one of the more common methods is to deal with the edge regions and homogeneous regions of the image respectively.Primal Sketch algorithm is a sparse representation of the image, and could get the singular information of the image, including the point targets and line targets. In this paper, SAR denosing work guided by Primal Sketch as follows:Before the SAR image denoising work, we firstly get the structure information of the SAR image by using the Primal Sketch algorithm, and do different filter processing with the structure regions and the homogeneous regions of the image respectively. This method can remove noise while keeping good image edge information. In this paper, experimental results were compared with other methods, confirmed the validity of the method.From the structural information of the images, combined with the aggregation of edge pixels and the idea of the anisotropy characteristics, to deal edge pixels, denoising while retaining the edge information better. In our experiment, this method is feasible; we improve the algorithm with the thoughts of the sliding window. The improved method could maintain the characteristics of detail better, and have a certain improvement in visual effect and edge preservation.