[GRASSLIST:2208] Re: How to display satellite data correctly?

[Wolfgang von Hansen]

Kris Nackaerts <knackaerts at gmx.net> schrieb am 13.01.04 22:09:11:
> 
> I had the same problem when trying to visualize hyperspectral images. I 
> created a script in R (www.r-project.org) to analyze the histogram 
> output files and create a GRASS script automatically to correctly 
> rescale the values for visualisation. I could then say like remove the 
> 5% tails.

I just wrote a small shell script myself which basically uses r.stats, awk and r.colors. Now everything is looking fine!

> If you are interested in this script, let me know. Otherwise, I also 
> used just a PCA transform to get a first impression of what was in the 
> images.

For the visualization of multispectral data it normally is sufficient to choose some interesting bands by their wavelength, but I agree with you that PCA is a good preprocessing step for visual inspection of a large number of bands.


Wolfgang
______________________________________________________________________________
Erdbeben im Iran: Zehntausende Kinder brauchen Hilfe. UNICEF hilft den
Kindern - helfen Sie mit! https://www.unicef.de/spe/spe_03.php