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Convert ASC file with Landuse data to Raster TIFF

zeltpsi
zeltpsi Global Mapper User

Hi, I have an ASC file with integer landuse data, values from 1 to 19. The file will imports into GM as elevation data. I cannot find a way to convert the loaded data to raster over the full range of the potential data (1-19). Since there is a one-to-one relationship with the raster (pixel) value to a landuse code, these values must be preserved. If I export the data as raster, it will find an optimal pallete and truncate my 1-19 to some other used range, say 1-9. But it does not provide the truncation used so If I re-import the file, it would be scrambled. The pallete for the loaded ASC cannot be assigned but only various shader options are available; at least I can't find a way to do it. Since the pallete for the loaded ASC cannot be assigned I can't export the file as raster using the available "use pallete from file" option, since this option interprets the pallete of the displayed data which I cannot change. Any ideas on how to convert the ASC data to landuse raster TIFF???

Answers

  • zeltpsi
    zeltpsi Global Mapper User

    I was able to re-classify the ASC file, using

    -Load ASC

    -Analysis->Raster Reclassify

    -'load a pallete file' (from the drop down for raster reclassification), for the desired colors and pixel values

    -assign a one-to-one pixel value, then reclassify

    -then export the reclassification as a GeoTiff