The manual of i.oif refers to LANDSAT TM bands 1-5, & 7. Why not for newer
Landsat products, e.g. ETM+?
Can/should we update the manual?
<http://grass.osgeo.org/grass70/manuals/i.oif.html>
Thanks, Nikos
On Fri, May 24, 2013 at 2:39 AM, Nikos Alexandris
<nik@nikosalexandris.net> wrote:
The manual of i.oif refers to LANDSAT TM bands 1-5, & 7. Why not for newer
Landsat products, e.g. ETM+?
Nobody picked it up so far... 
Can/should we update the manual?
Please go ahead, thanks.
Markus
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