[Gdal-dev] Alabama geotiff tiles are showing up in Virginia within mapserver

[John Mitchell]

Hi,

I have Alabama geotiff tiles which are showing up in Virginia within
mapserver.  If you look at the original gdalinfo against one of the tiles
you will see that the corner coordinates are within Alabama, but within
MapServer if you do on the fly projection(EPSG:26929 to EPSG:4326) it
instead shows up within the state of Virginia.  I also used gdalwarp to
change the projection from EPSG:26929 to EPSG:4326 and then displayed within
mapserver without having to reproject on the fly and it also shows up within
Virginia. Note: when running gdalinfo on the gdalwarp file which was
reprojected to EPSG:4326 it also has the coordinates within the state of
Virginia.

Below are the gdalinfo dumps first the original file and then the file that
was converted from EPSG:26929 to EPSG:4326

Driver: GTiff/GeoTIFF
Size is 10000, 10000
Coordinate System is:
PROJCS["NAD83 / Alabama East",
    GEOGCS["NAD83",
        DATUM["North_American_Datum_1983",
            SPHEROID["GRS 1980",6378137,298.2572221010002,
                AUTHORITY["EPSG","7019"]],
            AUTHORITY["EPSG","6269"]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433],
        AUTHORITY["EPSG","4269"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",30.5],
    PARAMETER["central_meridian",-85.83333333333333],
    PARAMETER["scale_factor",0.99996],
    PARAMETER["false_easting",656166.6666666665],
    PARAMETER["false_northing",0],
    UNIT["US survey foot",0.3048006096012192,
        AUTHORITY["EPSG","9003"]],
    AUTHORITY["EPSG","26929"]]
Origin = (723240.000000000000000,820340.000000000000000)
Pixel Size = (0.500000000000000,-0.500000000000000)
Metadata:
  AREA_OR_POINT=Area
  TIFFTAG_XRESOLUTION=72
  TIFFTAG_YRESOLUTION=72
  TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch)
Corner Coordinates:
Upper Left  (  723240.000,  820340.000) ( 85d36'54.59"W, 32d45'17.80"N)
Lower Left  (  723240.000,  815340.000) ( 85d36'54.71"W, 32d44'28.33"N)
Upper Right (  728240.000,  820340.000) ( 85d35'56.04"W, 32d45'17.69"N)
Lower Right (  728240.000,  815340.000) ( 85d35'56.17"W, 32d44'28.22"N)
Center      (  725740.000,  817840.000) ( 85d36'25.38"W, 32d44'53.01"N)
Band 1 Block=10000x1 Type=Byte, ColorInterp=Red
  Overviews: 1250x1250
Band 2 Block=10000x1 Type=Byte, ColorInterp=Green
  Overviews: 1250x1250
Band 3 Block=10000x1 Type=Byte, ColorInterp=Blue
  Overviews: 1250x1250

-------------------------------------------------------------------------------------------------------------------

Driver: GTiff/GeoTIFF
Size is 11930, 9476
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 = (-79.902533251890048,37.745881181682833)
Pixel Size = (0.000005030208747,-0.000005030208747)
Metadata:
  AREA_OR_POINT=Area
Corner Coordinates:
Upper Left  ( -79.9025333,  37.7458812) ( 79d54'9.12"W, 37d44'45.17"N)
Lower Left  ( -79.9025333,  37.6982149) ( 79d54'9.12"W, 37d41'53.57"N)
Upper Right ( -79.8425229,  37.7458812) ( 79d50'33.08"W, 37d44'45.17"N)
Lower Right ( -79.8425229,  37.6982149) ( 79d50'33.08"W, 37d41'53.57"N)
Center      ( -79.8725281,  37.7220481) ( 79d52'21.10"W, 37d43'19.37"N)
Band 1 Block=256x256 Type=Byte, ColorInterp=Red
Band 2 Block=256x256 Type=Byte, ColorInterp=Green
Band 3 Block=256x256 Type=Byte, ColorInterp=Blue


-- 
John J. Mitchell
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