Preprocess method for speckle interference image based on spin filtering

This paper introduces the filter effect after the image with speckle noise is processed by different spin filters window. Comparing the images processed by spin filters, it is proved that the spin filter window should be one-fourth of the fringe width, and must be larger than the speckle size to filter off noise for images with large speckle noise. The gray scale extension has been applied for the fringe image to increase the fringe contrast, which was reduced by the spin and median filter.