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I have 5-band composite orthomosaics that I wish to apply multiple vegetation indices towards. In the raster calculator, it only displays the raster, but not the individual bands. Can someone give me an example of how I would write out a calculation for something like NDVI? (NIR-Red)/(NIR+Red)

I imagine it is something like (Rastername Layer4 - Rastername Layer3) and so on. Just cannot seem to find anything online after much searching.

Naturally, I am aware that I could subset the bands of the images, but that seems counter-productive!

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  • Which software are you using? – ahmadhanb Jun 29 '16 at 1:06
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You need to use each single band as an image to do raster calculator in ArcGIS. Raster calculator cannot give you access to the multiple bands composited into a one image. However, you can access each band of the composite image from ArcCatalog.

  1. Navigate to the 5-band composite image from raster catalog,
  2. Drag and drop each band into ArcMap,
  3. Now you can use raster calculator to the calculate NDVI.

Another option is to use the raster calculator in QGIS. It gives you access to each band of the multiple bands directly from raster calculator, as you can see below

enter image description here

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I would suggest you to have a look at Image Analysis toolbar, which is very powerful and easy to use. In fact there is an in-built NDVI function as an answer to your query. Additonally I strongly suggest Band Aritmethic function in this tool for your possible further enquiries. Please see http://desktop.arcgis.com/en/arcmap/10.3/manage-data/raster-and-images/what-are-the-functions-used-by-a-raster-or-mosaic-dataset.htm

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  • Thanks Faith! the image analysis window is good but it only allows for NDVI. However I will try as Ahmad mentioned and import the bands in from arccatalog. – Alexander Jun 29 '16 at 16:02
  • I had exactly the same problem and either here or on Esri's geonet I have found out that, you may find it very assertive though, in ArcGIS Image Analysis is the way to go. It is maybe the fastest in this market and you can export your output later on by inspecting if the output is what you are after. For raster arithmetic operations, Band Arithmetic function is a charm. – fatih_dur Jun 29 '16 at 21:16
  • My last advice, try the answer first and work on Image Analysis functions and try this to see the difference. – fatih_dur Jun 29 '16 at 21:19

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