[GRASS-dev] [GRASS GIS] #2048: i.pansharpen limited to 8-bit imagery

[GRASS GIS]

#2048: i.pansharpen limited to 8-bit imagery
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 Reporter:  nikosa                                                     |       Owner:  grass-dev@…              
     Type:  defect                                                     |      Status:  new                      
 Priority:  normal                                                     |   Milestone:  7.0.0                    
Component:  Imagery                                                    |     Version:  svn-trunk                
 Keywords:  i.pansharpen, sharpening, fusion, brovey, ihs, pca, 8-bit  |    Platform:  Unspecified              
      Cpu:  All                                                        |  
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Comment(by nikosa):

 Replying to [comment:14 cmbarton]:
 > Does someone have a small sample set of images to test in order to work
 out alternatives to 8bit image matching?


 See, for example, publicly available IKONOS images:
 [ftp://ftp.glcf.umd.edu/glcf/China_earthquake_May_2008/IKONOS/].  I did
 all the series of tests (as postes in the mailing list) with the first one
 [ftp://ftp.glcf.umd.edu/glcf/China_earthquake_May_2008/IKONOS/po_58204_0000000.20001116
 .China-Sichuan/]

 I also have a small script to pan-sharpen DNs, Radiance and Reflectancs
 (given all of the pre-processing has been done and some naming conventions
 are followed):


 {{{
 for Method_Input in "ihs DNs" "ihs Radiance" "ihs ToAR" \
 "brovey DNs" "brovey Radiance" "brovey ToAR" \
 "pca DNs" "pca Radiance" "pca ToAR"

 do

   # parse "${Method_STR}" and set positional parameters
   set -- $Method_Input ; echo $1 $2

   # some echo
   echo "Pan-Sharpening the <${2}> images based on the <${1}> method"

   i.pansharpen \
   sharpen=${1} \
   pan=Pan_${2} \
   ms1=Blue_${2} \
   ms2=Green_${2} \
   ms3=Red_${2} \
   output=sharp_${1}_${2}

 done
 }}}



 > A key issue is that it will be necessary to know the potential value
 range for the images.

 If it's an 11-bit image, the the input can be fixed to [0,2047]?
 Actually, most of the data come in either 8-bit or 16-bit form.  The
 latter for not loosing the fine detail of >8-bit sensors (me thinks).


 > I don't see a way around this being a user-entered value. Maybe there
 also needs to be a flag for floating point.

 Can't this be automated in Python?  Right, RTFM for myself :D

-- 
Ticket URL: <https://trac.osgeo.org/grass/ticket/2048#comment:15>
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