NRS Tools: Pre-processing tools in ENVI/IDL

NRS Tools is a set of ENVI/IDL extensions that are developed over more than a decade for the Department of Natural Resources (NRS) of the Faculty of Geo-information Science and Earth Observation (ITC). The tools available include timeseries tools (e.g. harmonic analysis, harmonic composition, time aggregation and interpolation, upper-envelope filter), stack tools (e.g. compare stacks, reverse layers, remove bias, stack statistics, zonal operations), spectral tools (e.g. spectrum extraction), NDVI tools (e.g. relative phenological development, green wave index, growing degree days), and climate indices (e.g. precipitation indices, ETCCDI/CRD climate change indices). The tools are open-source and basic user documentation is available for most extensions.