Digital Geography

Freeware SAR processing, Part II: PolSARPro

In this post I’ll take you through some simple functions in the freeware polarimetric SAR processing package, PolSARPro. The software is distributed by the European Space Agency (ESA) and supports a wide range of dual- and quadpol datasets, including Radarsat-2, Envisat ASAR, SIR-C, EMISAR, and AIRSAR. I’ll be processing ALOS PALSAR in this example. The steps I will show are: Importing and Extracting data, calibration, speckle filtering and multilooking. We will finish by producing an Entropy-Alpha-Anisotropy dataset. Getting Started We start by identifying the directory in which our data lies. To do this we click on the first icon (highlighted…

Free Sources of Geospatial Raster Data

I’m always looking for good sources of free data, so I thought I would post a few here in case they were useful to others. The sources listed below tend to be larger providers of regional to global level data, however, please post suggestions in the comments if there are other sources you like and think should be added. I had initially planned to include vector data here, but I think that will be another post as this one got quite long. SAR Data Free Synthetic Aperture Radar data can be some of the hardest to find, but it is…