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I'm using arcpy.sa.SegmentMeanShift() to produce a segmented raster in ArcGIS 10.7.1.

The segments in the output raster have values outside the range of values (1 to 248) in the input raster (-22 to 92)!

The new range of values in looks like a fit for stretched values (0-255). But I need the original values, not the stretched values.

How can I get the (mean) original values in my segmented raster?

I have tried arcpy.SetRasterProperties_management(inputRaster, data_type="PROCESSED"), but this has not helped.

UPDATE: ESRI Rubbish...?

Turns out the problem doesn't always happen. I've changed my output to be in a geodatabase, and the problem went away! I haven't tested conclusively if this is why the problem went away... to busy moving on to other things.

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I have worked around this problem successfully by converting the values back to the unstretched values, using the formula for converting a number in one range to a number in another range as per, https://stackoverflow.com/questions/929103/convert-a-number-range-to-another-range-maintaining-ratio :

NewValue = (((OldValue - OldMin) * (NewMax - NewMin)) / (OldMax - OldMin)) + NewMin

But since I know that the stretched range (oldMin to oldMax) is 0-255, I can simplify the formula making it a little more specific to this range:

segRaster = ((segRaster * (newMax - newMin)) / 255) + newMin

This appears to be producing the correct results for me.

I'd still be interested to hear if there is any way to get the arcpy.sa.SegmentMeanShift() to produce un-stretched output.

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