Accepted paper in IEEE-GRSL

The paper,"Performance of speckle filters for COSMO-SkyMed images from the Brazilian Amazon", by Tahisa Kuck (Instituto de Estudos Avançados,, Sao Paulo, Brazil), Luis Gomez (CTIM, Universidad de Las Palmas de Gran Canaria, Edson E. Sano (Embrapa Cerrados, Brasilia, Bazil), Polyanna da C. Bispo (Department of Geography, School of Environment, Education and Development, University of Manchester, Oxford, UK) and Douglas D. C. Honorio (Instituto de Estudos Avançados,, Sao Paulo, Brazil), has been accepted for publication in IEEE-GRSL (in press).

IEEE Geoscience and Remote Sensing Letters (GRSL), Impact Factor 3.833, is a monthly publication for short papers (maximum length 5 pages) addressing new ideas and formative concepts in remote sensing as well as important new and timely results and concepts.


Speckle filtering is an important step for target detection in SAR images, since this effect makes difficult or even impossible to extract information from these images. There are several filters available in the literature, although evaluating their performances is not a trivial task, since it requires comparing the filtered images with a speckle-free image, which is generally unknown. This evaluation is even more complex when the features in the images, for example, from tropical forests, are heterogeneous. The objective of this study is to evaluate the performance of the Lee, deGrandi, GammaMAP, Wiener filters to reduce the speckle present in the COSMO-SkyMed Stripmap, X-band images from the Brazilian Amazon forest region. The evaluation was conducted qualitatively through the visual inspection of the ratio image and the edge detection in the ratio images, and quantitatively through the αβ estimator and other statistical parameters of the filtered images. The GammaMAP filter showed the best performances, both qualitatively and quantitatively, and FANS filter only qualitative. Index Terms—speckle filtering, SAR images, tropical forest, X-band.