SAR Image Compression Based on Multiwavelet Combining with Speckle Noise Reduction
Yushi Chen · Jisuanji fangzhen · 2008
Synthetic aperture radar(SAR) images are corrupted by multiplicative speckle noise which decreases correlation between adjacent pixels,increases the information entropy and limits the performance of the classical coder/decoder algorithms in spatial domain.The relatively new transform of multiwavelet can possess desirable features simultaneously,such as short support,orthogonality and symmetry,while scalar wavelets cannot.Thus a compression scheme combining with speckle noise reduction within the multiwavelet framework was proposed.After multiwavelet transform,modified soft-thresholding denoising method was applied to reduce speckle noise which protected more edge information at the meantime.Then multiwavelet coefficients were rearranged to reconstruct spatial orientation tree and coded by set partitioning in hierarchical trees(SPIHT) algorithm.Experimental results show this coding method achieves favorable peak signal to noise ratio(PSNR) and superior speckle noise reduction performances.