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I have an image which has had its band ordering rearranged, giving it a weird false color. I wanted to change it back to a natural color, so I used GDAL and through trial and error got the bands re-organised.

But i couldn't find out which bands where meant to be where.

  1. How do i find which bands are first in the array (gdalinfo does not do this, it just says there are 3 bands, red, green, blue)
  2. Are there any good online resources giving different band combinations for different applications?
  • Without metadata about which wavelengths have been written to which bands from the image provider you can just try. GDAL calls the first three bands as red, green, and blue and the bands are used like that when the image is painted on the screen. However, the first band can actually be a measure of green color in the nature but GDAL can't know it. – user30184 May 3 '16 at 9:18
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    It may not correspond to RGB at all. Some imagery may have more than one "red" band, or only be in non-visible IR for example. – BradHards May 3 '16 at 9:53
  • This may be helpful: gis.stackexchange.com/a/175557/8104 – Aaron May 4 '16 at 0:43
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There is no definitive way to determine the bands without vendor metadata. However, you can infer which bands are which by looking at a spectral profile of image reflectance values at features such as water and vegetation. For example, near infrared values in your imagery will be very low for water features and very high for healthy green vegetation. The red portion of the EM Spectrum is highly absorbed by healthy green vegetation and will therefore have low values compared to the other bands.

Regarding band combination, the USGS has good information on band combinations for Landsat 5,7,8 (USGS Source).

enter image description here

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