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Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.

NAME

i.oif - Calculates Optimum-Index-Factor table for spectral bands

KEYWORDS

imagery, multispectral, statistics

SYNOPSIS

i.oif
i.oif --help
i.oif [-gs] input=name[,name,...] [output=name] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-g
Print in shell script style
-s
Process bands serially (default: run in parallel)
--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:

input=name[,name,...] [required]
Name of input raster map(s)
output=name
Name for output file (if omitted or "-" output to stdout)

Table of contents

DESCRIPTION

i.oif calculates the Optimum Index Factor for multi-spectral satellite imagery.

The Optimum Index Factor (OIF) determines the three-band combination that maximizes the variability (information) in a multi-spectral scene. The index is a ratio of the total variance (standard deviation) within and the correlation between all possible band combinations. The bands that comprise the highest scoring combination from i.oif are used as the three color channels required for d.rgb or r.composite.

The analysis is saved to a file in the current directory called "i.oif.result".

NOTES

Landsat 1-7 TM: Colour Composites in BGR order as important Landsat TM band combinations (example: 234 in BGR order means: B=2, G=3, R=4):

By default the module will calculate standard deviations for all bands in parallel. To run serially use the -s flag. If the WORKERS environment variable is set, the number of concurrent processes will be limited to that number of jobs.

EXAMPLE

North Carolina sample dataset:
g.region raster=lsat7_2002_10 -p
i.oif input=lsat7_2002_10,lsat7_2002_20,lsat7_2002_30,lsat7_2002_40,lsat7_2002_50,lsat7_2002_70

REFERENCES

Jensen, 1996. Introductory digital image processing. Prentice Hall, p.98. ISBN 0-13-205840-5

SEE ALSO

d.rgb, r.composite, r.covar, r.univar

AUTHORS

Markus Neteler, ITC-Irst, Trento, Italy
Updated to GRASS 5.7 by Michael Barton, Arizona State University

SOURCE CODE

Available at: i.oif source code (history)

Latest change: Mon Nov 18 20:15:32 2019 in commit: 1a1d107e4f6e1b846f9841c2c6fabf015c5f720d


Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.

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