A have a GeoTIFF LIDAR image which display DEM in its color-ramp version (color relief) from blue (minimum value) to red (maximum value) and green (in between).
I don’t have the original elevation data.
Is there any application or algorithm to turn this ‘color coded’ maps into its original DEM? (elevation data).
Suppose from another measurement, I know the elevation at multiple point in the DEM to reference the color-map. (or in case I’m sure that some region is the sea, I’ll assign zero to it).