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I have a multiband raster (RGB) and I'd like to select out the watercourses to create a new raster.

enter image description here

Examining the data it seems I can do so by selecting blue > 100, Red <100, Green <100. Is there a way to create a new raster based on an sql query, where all pixels that meet the criteria are differentiated from those that don't?

I have the spatial analyst extension. I saw the Extract By Attributes tool, but this just allows me to select by Value.

enter image description here

Ideally my end product would be a binary raster that differentiates between those pixels that meet the given criteria and those that do not.

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  • I can remember someone telling me this was 'easy' in photoshop (and GIMP too I suppose), it might be worth your while looking around in those forums; beware that raster editors destroy georeference in GeoTIFFs - they don't recognize Geo Tags but instead of just maintaining the values they don't understand (garbage-in garbage-out) they tend to not write them... The good news is that World files aren't affected so you can use TFW files to bank your georeference.
    – Michael Stimson
    Commented Dec 20, 2017 at 5:28

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Add each band to ArcMap individually. Use Con to evaluate your expression in the raster calculator:

Con(("Blue" > 100) & ("Red" < 100) & ("Green" < 100), 1)

Which will output a raster of 1 and NoData. If you want 1 and 0 output, just use:

(("Blue" > 100) & ("Red" < 100) & ("Green" < 100))
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I have had no success trying to do what you are doing. I use image classification now and have reasonable success when features I am looking to pull are very different than their surroundings; it appears that this is your case:

http://desktop.arcgis.com/en/arcmap/latest/extensions/spatial-analyst/image-classification/image-classification-using-spatial-analyst.htm

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