[gdal-dev] gdalinfo: Corner Coordinates

[Emilio de Torres Fernández]

Hello,

I'm trying to understand the corner coordinates info of the following
gdalinfo output:

Driver: GTiff/GeoTIFF
Files: mosaicoRe.tif
Size is 2674, 2649
Coordinate System is:
PROJCS["unnamed",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563,
                AUTHORITY["EPSG","7030"]],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Azimuthal_Equidistant"],
    PARAMETER["latitude_of_center",-6.2500000000005],
    PARAMETER["longitude_of_center",36.5166666666677],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]]]
Origin = (-4195457.111657013185322,5006607.738502652384341)
Pixel Size = (14.156374416158000,-14.156374416158000)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=PIXEL
Corner Coordinates:
Upper Left  (-4195457.112, 5006607.739) (  6d32'32.13"W, 36d42'16.93"N)
Lower Left  (-4195457.112, 4969107.503) (  6d25'25.65"W, 36d24'11.72"N)
Upper Right (-4157602.966, 5006607.739) (  6d 9'42.57"W, 36d44'40.08"N)
Lower Right (-4157602.966, 4969107.503) (  6d 2'38.96"W, 36d26'32.65"N)
Center      (-4176530.039, 4987857.621) (  6d17'34.10"W, 36d34'25.64"N)
Band 1 Block=2674x1 Type=Byte, ColorInterp=Red
Band 2 Block=2674x1 Type=Byte, ColorInterp=Green
Band 3 Block=2674x1 Type=Byte, ColorInterp=Blue



I'm focusing in the Upper Left info:

      * The first pair of numbers are the coordinates of the upper left
        corner in the spatial reference set ot an azimuthal equidistant
        projection.
      * The second pair is the long-lat of the same upper left corner.


If I use the  equations of the azimuthal equidistant projection to
transform   long=6d32'32.13"W and  lat=36d42'16.93"N) I get x = -0.65688
and y = 0.78961, not (-4195457.112, 5006607.739). Why??? I guess I
misunderstood some concept of the "Corner Coordinates" of gdalinfo.

Best regards



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