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<h2>DESCRIPTION</h2>
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-<em>i.oif</em> calculates the Optimum Index Factor for LANDSAT TM bands 1,2,3,4,5 and 7.
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-<p>The Optimum Index Factor is calculated to determine the band combination which
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-shows the maximum information when combined into a composite image. The bands
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-comprising the highest scoring combination from <em>i.oif</em> are used as the
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-three color channels required for <em>d.rgb</em> or <em>r.composite</em>.
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+<em>i.oif</em> calculates the Optimum Index Factor for
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+multi-spectral satellite imagery.
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+
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+<p>
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+The Optimum Index Factor (OIF) determines the three-band combination
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+that maximizes the variability (information) in a multi-spectral
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+scene. The index is a ratio of the total variance (standard
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+deviation) within and the correlation between all possible band
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+combinations. The bands that comprise the highest scoring
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+combination from <em>i.oif</em> are used as the three color channels
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+required for <em>d.rgb</em> or <em>r.composite</em>.
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+
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<p>The analysis is saved to a file in the current directory called "i.oif.result".
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<h2>NOTES</h2>
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-Colour Composites in BGR order: important band combinations (example:
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-234 in BGR order means: B=2, G=3, R=4):
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+Landsat TM:
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+Colour Composites in BGR order as important Landsat TM band combinations
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+(example: 234 in BGR order means: B=2, G=3, R=4):
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<ul>
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-<li> 123: near natural ("true") colour; however, because of correlation of
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-the 3 bands in visible spectrum, this combination contains not much more
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-info than is contained in single band.
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-
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-<li> 234: sensitive to green vegetation (portrayed as red), coniferous as
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-distinctly darker red than deciduous forests. Roads and water bodies are clear.
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-
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-<li> 243: green vegetation is green but coniferous forests aren't as clear as
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-the 234 combination.
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-
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-<li> 247: one of the best for info pertaining to forestry. Good for operation
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-scale mapping of recent harvest areas and road construction.
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-
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-<li> 345: contains one band from each of the main reflective units (vis, nir,
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-shortwave infra). Green vegetation is green and the shortwave band shows
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-vegetational stress and mortality. Roads are less evident as band 3 is blue.
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-
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-<li> 347: similar to 345 but depicts burned areas better.
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-<li> 354: appears more like a colour infrared photo.
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-<li> 374: similar to 354.
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-<li> 457: shows soil texture classes (clay, loam, sandy).
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+<li> 123: near natural ("true") colour; however, because of
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+correlation of the 3 bands in visible spectrum, this combination
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+contains not much more info than is contained in single band.</li>
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+<li> 234: sensitive to green vegetation (portrayed as red),
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+coniferous as distinctly darker red than deciduous forests. Roads
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+and water bodies are clear.</li>
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+<li> 243: green vegetation is green but coniferous forests aren't as
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+clear as the 234 combination.</li>
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+<li> 247: one of the best for info pertaining to forestry. Good for
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+operation scale mapping of recent harvest areas and road
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+construction.</li>
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+<li> 345: contains one band from each of the main reflective units
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+(vis, nir, shortwave infra). Green vegetation is green and the
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+shortwave band shows vegetational stress and mortality. Roads are
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+less evident as band 3 is blue.</li>
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+<li> 347: similar to 345 but depicts burned areas better.</li>
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+<li> 354: appears more like a colour infrared photo.</li>
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+<li> 374: similar to 354.</li>
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+<li> 457: shows soil texture classes (clay, loam, sandy).</li>
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</ul>
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<p>
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@@ -56,7 +62,8 @@ i.oif image1=lsat7_2002_10 image2=lsat7_2002_20 image3=lsat7_2002_30 \
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<h2>REFERENCE</h2>
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-Jensen, 1996. Introductory digital image processing. Prentice Hall, p.98. ISBN 0-13-205840-5
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+Jensen, 1996. Introductory digital image processing. Prentice Hall,
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+p.98. ISBN 0-13-205840-5
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<h2>SEE ALSO</h2>
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@@ -69,7 +76,7 @@ Jensen, 1996. Introductory digital image processing. Prentice Hall, p.98. ISBN 0
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</em>
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-<h2>AUTHOR</h2>
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+<h2>AUTHORS</h2>
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Markus Neteler, ITC-Irst, Trento, Italy<br>
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Updated to GRASS 5.7 by Michael Barton, Arizona State University
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Markus Neteler