U.S. Geological Survey Open-File Report 2010-1332
Figure 12. The 6-hour-long GLORIA pass with the aspect-ratio distortion corrected and speckle noise removal applied. The applied speckle noise removal filter also helps reduce the blockiness introduced into the image by the aspect-ration distortion correct. This is the final processing of the 6-hour-long pass before digital mosaicking can proceed (Twichell, 1988).