Nikos A wrote: > > The manual of i.oif refers to LANDSAT TM bands 1-5, & 7. Why not for > > newer Landsat products, e.g. ETM+?
Markus N: > Nobody picked it up so far... :) > > Can/should we update the manual? > > <http://grass.osgeo.org/grass70/manuals/i.oif.html> > Please go ahead, thanks. I wonder if (and how) we should alter the parameters descriptions as well. I mean, the OIF concept is (in theory) applicable to any three-band/image combination (let them be spectral bands or else, given they are in the same unit). Proposed changes for the manual: --%<--- svn diff i.oif.html Index: i.oif.html =================================================================== --- i.oif.html (revision 56333) +++ i.oif.html (working copy) @@ -1,16 +1,18 @@ <h2>DESCRIPTION</h2> -<em>i.oif</em> calculates the Optimum Index Factor for LANDSAT TM bands 1,2,3,4,5 and 7. -<p>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 <em>i.oif</em> are used as the -three color channels required for <em>d.rgb</em> or <em>r.composite</em>. +<em>i.oif</em> calculates the Optimum Index Factor for multi-spectral satellite imagery. +<p>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 <em>i.oif</em> are used as the three color channels +required for <em>d.rgb</em> or <em>r.composite</em>. <p>The analysis is saved to a file in the current directory called "i.oif.result". <h2>NOTES</h2> -Colour Composites in BGR order: important band combinations (example: +Colour Composites in BGR order: important Landsat TM band combinations (example: 234 in BGR order means: B=2, G=3, R=4): <ul> @@ -29,7 +31,7 @@ <li> 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. +vegetation stress and mortality. Roads are less evident as band 3 is blue. <li> 347: similar to 345 but depicts burned areas better. <li> 354: appears more like a colour infrared photo. --->%-- Thanks, Nikos _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
