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i.oif - Calculates Optimum-Index-Factor table for LANDSAT TM bands 1-5, & 7
raster, imagery, statistics
i.oif [-g] image1=string image2=string image3=string image4=string image5=string image7=string [--verbose] [--quiet]
- Print in shell script style
- Verbose module output
- Quiet module output
- LANDSAT TM band 1.
- LANDSAT TM band 2.
- LANDSAT TM band 3.
- LANDSAT TM band 4.
- LANDSAT TM band 5.
- LANDSAT TM band 7.
i.oif calculates the Optimum Index Factor for LANDSAT TM bands 1,2,3,4,5
The Optimum Index Factor is calculated to determine the band combination which
shows the maximum information when combined into a composite image. The bands
comprising 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".
Colour Composites in BGR order as important Landsat TM band combinations
(example: 234 in BGR order means: B=2, G=3, R=4):
- 123: near natural ("true") colour; however, because of
correlation of the 3 bands in visible spectrum, this combination
contains not much more info than is contained in single band.
- 234: sensitive to green vegetation (portrayed as red),
coniferous as distinctly darker red than deciduous forests. Roads
and water bodies are clear.
- 243: green vegetation is green but coniferous forests aren't as
clear as the 234 combination.
- 247: one of the best for info pertaining to forestry. Good for
operation scale mapping of recent harvest areas and road
- 345: contains one band from each of the main reflective units
(vis, nir, shortwave infra). Green vegetation is green and the
shortwave band shows vegetational stress and mortality. Roads are
less evident as band 3 is blue.
- 347: similar to 345 but depicts burned areas better.
- 354: appears more like a colour infrared photo.
- 374: similar to 354.
- 457: shows soil texture classes (clay, loam, sandy).
North Carolina sample dataset:
g.region rast=lsat7_2002_10 -p
i.oif image1=lsat7_2002_10 image2=lsat7_2002_20 image3=lsat7_2002_30 \
image4=lsat7_2002_40 image5=lsat7_2002_50 image7=lsat7_2002_70
Jensen, 1996. Introductory digital image processing. Prentice Hall,
p.98. ISBN 0-13-205840-5
Markus Neteler, ITC-Irst, Trento, Italy
Updated to GRASS 5.7 by Michael Barton, Arizona State University
Last changed: $Date: 2013-11-15 12:39:04 -0800 (Fri, 15 Nov 2013) $
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