[gdal-dev] Question to Gdalinfo result

[Markus Neteler]

On Wed, Nov 5, 2008 at 4:18 PM, Kai Behncke <Kai-Behncke at gmx.de> wrote:
> Dear users, I have an aerial image and did a "gdalinfo" to it:
>
>
> The result is (extract):
> --------------------------------------------
> Coordinate System is:
> GEOGCS["WGS 84",
>    DATUM["WGS_1984",
>        SPHEROID["WGS 84",6378137,298.2572235630016,
>            AUTHORITY["EPSG","7030"]],
>        AUTHORITY["EPSG","6326"]],
>    PRIMEM["Greenwich",0],
>    UNIT["degree",0.0174532925199433],
>    AUTHORITY["EPSG","4326"]]
> Origin = (8.028439291266251,52.303510658986561)
> Pixel Size = (0.000004896399317,-0.000004896399317)
> Metadata:
>  AREA_OR_POINT=Area
> Image Structure Metadata:
>  INTERLEAVE=PIXEL
> Corner Coordinates:
> Upper Left  (   8.0284393,  52.3035107) (  8d 1'42.38"E, 52d18'12.64"N)
> Lower Left  (   8.0284393,  52.2664645) (  8d 1'42.38"E, 52d15'59.27"N)
> Upper Right (   8.0498072,  52.3035107) (  8d 2'59.31"E, 52d18'12.64"N)
> Lower Right (   8.0498072,  52.2664645) (  8d 2'59.31"E, 52d15'59.27"N)
> Center      (   8.0391232,  52.2849876) (  8d 2'20.84"E, 52d17'5.96"N)
> -----------------------------
>
> All right, the most seems very clear to me, but does anybody know what:
>
>            AUTHORITY["EPSG","7030"]],
>        AUTHORITY["EPSG","6326"]],
>
>    UNIT["degree",0.0174532925199433],
>    AUTHORITY["EPSG","4326"]]
>
> mean??

See
 http://www.epsg-registry.org/
 -> retrieve by code
    -> 6326
      ->  "World Geodetic System 1984
	    ... Code: EPSG::6326
	    ..."
           -> View

Like this you can look up these authoritative codes.
In GDAL they are used in lookup-tables etc.

Markus