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I calculated NDVI in ENVI by band math. When I drag and drop the image in ArcMap it becomes a black image with stretched value =0 for all pixels. However, by identity clicking each pixel has a value equal to NDVI. Is there any solution to solve the problem? image in ENVI image in ArcMap

  • so what extension did you save it in ENVI. You may need to change to a different image type. In a couple of years ago , I work with both ENVI and ArcMap software and they do not read each other very well so you would to figure it out to save to different image type like tiff , png, geotiff, etc.. – PROBERT Dec 18 '17 at 16:03
  • ArcGIS should handle bil formats just fine. First, make sure that you give the output file a *.bil file extension and second, make sure that you calculate statistics on the file. – Jeffrey Evans Dec 18 '17 at 16:09
  • actually, ENVI saves the file without an extension! I exported it with *.bil extension but it does not work because the pixel values are between -1 and +1 but *.bil only shows integer values. – Javad Koohpayma Dec 18 '17 at 16:19
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I guess that you have to calculate the image statistic in ArcGIS. You can do that by using the Calculate Statistics tool or via the context menu (right-click on the raster file) in ArcCatalog. After that, you can apply the appropriate stretching method in ArcMap. If you have Nodata values in your raster file you have to specify them as Jessica already mentioned.

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I'm not sure if this will solve your problem (I haven't used ArcMap in ages, and without knowing more about your files it's hard to say what's going on), but you could check to make sure ArcMap is properly handling any no data or NaN values that ENVI might have been handling automatically (e.g. to deal with 0 in the denominator). You should also manually change the layer display options in ArcMap to match those in ENVI (ENVI will often automatically display based on a stretch between the max and min values of your data, but this display information is not stored as part of the file).

  • yes, you are right ENVI handle no data automatically, also it is possible to add stretch to the image but I couldn't export it to arcmap. – Javad Koohpayma Dec 18 '17 at 16:16

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