A Non-Local Means Filters for Sar Speckle Reduction with Likelihood Ratio Test

SAR imagery is always accompanied by speckle because it is obtained with coherent illumination. Given the multiplica-tive property of speckle, ratio-based metrics are widely used in SAR image quality assessment. In this paper, using the hy-potheses testing principle, a likelihood ratio test (LRT) based metric was designed for similarity measure in intensity SAR imagery. Then, using non-local means (NLM) scheme, an LRT-based NLM filter was proposed for speckle reduction of SAR imagery. In the experiments, using simulated intensity speckled images, the performance of the designed method is analyzed.