Abstract:

A new filtering algorithm smoothing function based on gradient was proposed. Based on gradient, noise points are identified. This algorithm is based on the spatial curved surface fitting, and then the surface is processed through smoothing function. The good pixels are unsmooth. The results of experiment, using the data which come from ALOS data of Beijing, show that the smoothing function filer has effectiveness and feasibility. The RMS (Root mean square error), PSNR (Peak signal-to-noise ratio), EPI(Edge preserve index) and PSD (Phase standard deviation) suggest that the algorithm can reduce the speckle noise and keep the edge information.

Key words: InSAR, adaptive, smoothing function, filter, speckle