Spectral Library Exchange Format (SLEF)

Question: 

What is the Spectral Library Exchange Format (SLEF) that some of ENVI's THOR tools can work with?

Answer:

The SLEF is a "format" that was developed by a number of intelligence agencies that were dealing with spectral signature data and wanted a common way to store not just signature data, but also metadata (classification, who collected it, details about material, where it was collected, when it was collected, etc.). 

The the SLEF consists of a simple comma separated value (CSV) text file.  The top section is:

   Metadata field name, metadata value

The bottom section is:

   Wavelength value, data value(, additional data values if more than one signature, all separated by commas)

THOR has the capability to ingest multiple SLEF files and combine them into a Metadata Rich Spectral Library (MRSL), or resample them all to common wavelengths (and strip all metadata) to form an ENVI spectral library file.

 

reviewed 8/28/14 PS & KK