For all ArcGIS extractors - Install ArcGIS Desktop Edition 10.3 with spatial analyst extension enabled. Also install arcpy and python that comes with ArcGIS. Set the PythonPath for the python under ArcGIS so that you can call arcpy anywhere in your system.
Extractors are in this repository:
https://opensource.ncsa.illinois.edu/bitbucket/projects/CATS/repos/extractors-bd-cz/browse
NDVI Extractor
Mosaics several scenes of Landsat 7 images, clips it based on a study region and computes Normalized Difference Vegetation Index (NDVI), and uploads the results to Clowder.
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