A NOVEL LOCAL DESPECKLING ALGORITHM FOR SAR IMAGE

A novel despeckling algorithm for synthetic aperture radar (SAR) image is presented. This algorithm focuses on despeckling a local region for each target pixel. Thus, the calculations of similarities and weights are located within a limited region rather than the entire image. Also, the similarity is measured by using the Euclidean distance of features between the target pixel and neighborhood pixel. In addition, a cosine integral image technique is applied to this scheme to improve the computation efficiency. The weight function is first decomposed into a linear combination of cosine functions, and each convolution with a cosine function requires a constant number of operations per pixel. Then, all the summation operations are carried out by the summed image method. A series of experiment results demonstrates the effectiveness of our method.