An effective algorithm for suppressing speckle in synthetic aperture radar（SAR）images utilizing the empirical mode decomposition（EMD）method is presented in this paper.The EMD was proposed by Norden E Huang et al .

with which any complicated data set can be decomposed into a finite and often small number of intrinsic mode functions.Contrary to almost all previous methods

this new method is intuitive

direct

a posterior and adaptive

with the basis of the decomposition based on

and derived from

the data.So EMD is quite suitable for analyzing nonlinear and non

s

tationary data.A line of digital SAR images can be decomposed into a series of modes whose characteristic space scale defined by the space lapse between the extrema is different.The speckle noise is defined by the mode whose space scale is not more than 4.The SAR speckle suppression is implemented by smearing short space scale component in the spatial domain via the EMD.As the EMD is one

d

imensional method

we use EMD in the following way.First we process each horizontal row of pixels

then process each column pixel of image. EMD is based on and derived from the data

thus it is adaptive and can preserve the edge information.Application to SAR images has shown that the performance of the algorithm is satisfactory in both smoothing and edge preservation.