Fig. 1

Fig. 2

Fig. 3

A selection of current widely available spectral libraries (based on Xie et al_ 2020, modified)_
| Release year | Spectral library | Institution |
|---|---|---|
| 1978 | Infrared spectrogram database | Shanghai institute of organic chemistry, Chinese Academy of Sciences |
| 1981 | JPL spectral library | Jet propulsion laboratory JPL, California Institute of Technology |
| 1990 | ICGP-264 spectral library | United States Geological Survey USGS |
| 1990 | Ground object reflectance spectral characteristics database | Institute of optical machinery, Chinese Academy of Sciences |
| 1991 | JHU spectral library | Johns Hopkins University JHU |
| 1993 | USGS spectral library | United States Geological Survey USGS |
| 1998, 2008 | ASTER spectral library (version 1 and 2) | America's space agency, NASA |
| 2000 | ASU Thermal infrared spectrum library | Arizona State University ASU |
| 2002 | China typical feature spectrum library | Beijing Normal University |
| 2007 | National typical ground object spectrum database for e-government | Institute of Remote Sensing Earth, Chinese Academy of Sciences |