IDL> file='TollhouseSuperCubeNNref.tif'

IDL> e=ENVI(/Headless)

ENVI> raster=e.OpenRaster(file)

ENVI> task=ENVITask('QuerySpectralIndices')

ENVI> task.Input_Raster=raster

ENVI> task.Execute

ENVI> help,task.Available_Indices
<Expression>    STRING    = Array[44]

ENVI> for i=0,n_elements(task.Available_Indices)-1 do print,' - '+task.Available_Indices[i]
 - Anthocyanin Reflectance Index 1
 - Anthocyanin Reflectance Index 2
 - Atmospherically Resistant Vegetation Index
 - Burn Area Index
 - Clay Minerals
 - Difference Vegetation Index
 - Enhanced Vegetation Index
 - Ferrous Minerals
 - Global Environmental Monitoring Index
 - Green Atmospherically Resistant Index
 - Green Difference Vegetation Index
 - Green Normalized Difference Vegetation Index
 - Green Ratio Vegetation Index
 - Green Vegetation Index
 - Infrared Percentage Vegetation Index
 - Iron Oxide
 - Leaf Area Index
 - Modified Chlorophyll Absorption Ratio Index
 - Modified Chlorophyll Absorption Ratio Index - Improved
 - Modified Non-Linear Index
 - Modified Simple Ratio
 - Modified Triangular Vegetation Index
 - Modified Triangular Vegetation Index - Improved
 - Non-Linear Index
 - Normalized Burn Ratio
 - Normalized Difference Built-Up Index
 - Normalized Difference Snow Index
 - Normalized Difference Vegetation Index
 - Optimized Soil Adjusted Vegetation Index
 - Red Edge Position Index
 - Red Green Ratio Index
 - Renormalized Difference Vegetation Index
 - Simple Ratio
 - Soil Adjusted Vegetation Index
 - Sum Green Index
 - Transformed Chlorophyll Absorption Reflectance Index
 - Transformed Difference Vegetation Index
 - Visible Atmospherically Resistant Index
 - WorldView Built-Up Index
 - WorldView Improved Vegetative Index
 - WorldView New Iron Index
 - WorldView Non-Homogeneous Feature Difference
 - WorldView Soil Index
 - WorldView Water Index

ENVI> e.close