Overview of This Tutorial - Department of Geosciences

Tutorial: Hyperspectral Signatures and Spectral Resolution

18. See

Draw Conclusions

on page 19, and answer some of the questions pertaining to GER63 data.

19. When you are finished, close the display group, ENVI Plot Window, and Spectral Profile. Keep the

Spectral Library Plots window open for the remaining exercises.

View HyMap Image and Spectra

HyMap is a state-of-the-art, aircraft-mounted, hyperspectral sensor developed by Integrated Spectronics,

Sydney, Australia, and operated by HyVista Corporation. HyMap provides unprecedented spatial, spectral and

radiometric resolution (Cocks et al., 1998). The system has a whiskbroom scanner utilizing diffraction gratings

and four 32-element detector arrays to provide 126 spectral channels covering the 0.44 - 2.5 µm range over a

512-pixel swath. Spectral resolution varies from 10 - 20 nm with 3 – 10 m spatial resolution and a signal-to-

noise ratio over 1000:1. The HyMap data described here were acquired on September 11, 1999. Selected

analysis results were published in Kruse et al. (1999). The plot below shows ROI mean spectra for kaolinite,

alunite, and buddingtonite.

View HyMap Mean Kaolinite and Alunite Image Spectra

1. From the ENVI main menu bar, select Window → Start New Plot Window. A blank ENVI Plot

Window appears.

2. From the ENVI Plot Window menu bar, select File → Input Data → ASCII. A file selection dialog

appears.

ENVI Tutorial: Hyperspectral Signatures and Spectral Resolution