Hello has anyone got experience running i.landsat.toar ?

The output files I get are empty, the command takes but a moment to complete. However when run in verbose mode all the calculations are done, it just does not complete the filling of the raster.

I am working on Win7 with GRASS7SVN. I am processing Landsat 5. I have taken care to reproject the images properly since there is incorrect metadata for Landsat in the southern hemisphere. The file paths are short and space free.

I note the following, but these don't appear to be directly related to my problem.



and the latest manual at


Any thoughts appreciated.

Some output;

BAND 5  (code 5)
   calibrated digital number (DN): 1.0 to 255.0
   calibration constants (L): -0.370 to 30.200
   at-surface radiance = 0.12035 * DN + 0.48667
   mean solar exoatmospheric irradiance (ESUN): 220.000
   at-surface reflectance = radiance / 60.70201
   the darkness DN with a least 100 pixels is 1
   the mode of DN is 0
 BAND 6 thermal  (code 6)
   calibrated digital number (DN): 1.0 to 255.0
   calibration constants (L): 1.238 to 15.303
   at-surface radiance = 0.05537 * DN + 1.18263
   at-sensor temperature = 1260.560 / log[(607.760 /
radiance) + 1.0]
 BAND 7  (code 7)
   calibrated digital number (DN): 1.0 to 255.0
   calibration constants (L): -0.150 to 16.500
   at-surface radiance = 0.06555 * DN + 0.16508
   mean solar exoatmospheric irradiance (ESUN): 83.440
   at-surface reflectance = radiance / 23.06338
   the darkness DN with a least 100 pixels is 1
   the mode of DN is 0
Writing reflectance of <5_9384_20101227_1> to <5_9384_20101227_toar_1>...
Writing reflectance of <5_9384_20101227_2> to <5_9384_20101227_toar_2>...
Writing reflectance of <5_9384_20101227_3> to <5_9384_20101227_toar_3>...
  • wow Nathan how did you do that?
    – BWill
    May 4, 2011 at 5:21

1 Answer 1


I have used i.landsat.toar recently with Landsat5 (on Linux) and hence updated its documentation accordingly as now found in SVN. For me no problem with the module. Suggestion: be sure that the computational region is correct. It must match the data of course, I suspect that you are off-map right now.

For example (before running i.landsat.toar):

g.region rast=5_9384_20101227_1 -p

or in the wxGUI, use "zoom to map" and then "set computational region from display" (don't remember the precise wording).

  • BINGO ! Thanks Markus, I did two things, created a new location and used the wxGUI to implement the command as you described.
    – BWill
    May 5, 2011 at 4:44
  • Glad it helped and glad that the wxGUI-extension manager finally works!
    – markusN
    May 6, 2011 at 7:04
  • Hi Markus, no the extension manager does not work in any of the GRASS versions I have tried. In GRASS7svn it comes up with the error, "Windows can't open this file g.extension.py". The i.landsat.xxx plugins are part of the G7svn distribution which is why I am using it.... The other GRASS 6.4.xxx distributions for windows also do not have functional plugin manager.
    – BWill
    May 7, 2011 at 11:51
  • The plan is to turn the flugin manager for Windows simply into a binary download and to precompile the Addons on our server. Hopefully just a matter of time.
    – markusN
    May 7, 2011 at 20:16
  • FWIW: Meanwhile i.landsat.toar made it into core GRASS GIS. Will be shipped with GRASS 6.4.3 and later (or grab the current snapshot).
    – markusN
    Oct 17, 2012 at 18:18

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