NAME

i.spectral - Displays spectral response at user specified locations in group or images.

KEYWORDS

imagery, querying, raster, multispectral

SYNOPSIS

i.spectral
i.spectral --help
i.spectral [-cgt] [group=name] [subgroup=name] [raster=name[,name,...]] coordinates=east,north[,east,north,...] [output=name] [format=string] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-c: Show sampling coordinates instead of numbering in the legend
-g: Use gnuplot for display
-t: output to text file
--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

group=name: Name of input imagery group
subgroup=name: Name of input imagery subgroup
raster=name[,name,...]: Name of input raster map(s)
coordinates=east,north[,east,north,...] [required]: Coordinates
output=name: Name for output image (or text file for -t)
format=string: Graphics format for output file
Options: png, eps, svg
Default: png

DESCRIPTION

i.spectral displays spectral response at user specified locations in images.

NOTES

This script needs gnuplot to be installed.

EXAMPLE

Analysis of LANDSAT TM7 channels (North Carolina dataset):


g.region raster=lsat7_2002_10 -p
i.spectral -g input=lsat7_2002_10,lsat7_2002_20,lsat7_2002_30,lsat7_2002_40,lsat7_2002_50,lsat7_2002_70 \
           coordinates=636069,215440,637958,223393,633277,223605

Spectral plot of 3 different land cover types: (1) water, (2) green vegetation, and (3) highway

North Carolina sample dataset:


g.region raster=lsat7_2002_10 -p
LIST=`g.list type=raster pattern="lsat7_2002_[1-5,7]0" separator=","`
i.spectral input=$LIST coordinates=637502.25,221744.25

This will search all LANDSAT map for 2002 but select only the B, G, R, NIR, and MIR channels.

AUTHOR

Markus Neteler
Francesco Pirotti

SOURCE CODE

Available at: i.spectral source code (history)