[Gdal-dev] Confusion with gdalwarp

[R. Piepul]

>>>>> "Frank" == Frank Warmerdam <warmerdam at pobox.com> writes:

    Frank> R. Piepul wrote:
    >> I seem to have a misunderstanding about the use of gdalwarp and
    >> am hoping that someone can tell me what is wrong.  I am trying
    >> to prepare a GeoTiff image for use in mapserver.

    Frank> ...

    >> $ gdalwarp -t_srs 'proj=utm zone=14' map.tif temp1.tif
    >> :0...10...20...30...40...50...60...70...80...90...100 - done.

    Frank> Rob,

    Frank> I would encourage you to explicitly include an ellipse in
    Frank> PROJ.4 declarations.  You are also encouraged to explicitly
    Frank> include a '+' in front of PROJ.4 options.  The above
    Frank> apparently works, but not because I have been careful to
    Frank> make it work.  So I would suggest:

    Frank>   -t_srs '+proj=utm +zone=14 +datum=NAD83'

    >> $ gdalinfo temp1.tif Driver: GTiff/GeoTIFF Size is 4879, 4536
    >> Coordinate System is `' Corner Coordinates: Upper Left ( 0.0,
    >> 0.0) Lower Left ( 0.0, 4536.0) Upper Right ( 4879.0, 0.0) Lower
    >> Right ( 4879.0, 4536.0) Center ( 2439.5, 2268.0) Band 1
    >> Block=4879x1 Type=Byte, ColorInterp=Gray $
    >> 
    >> 
    >> $ gdal-config --version 1.1.8 $ gdal-config --ogr-enabled yes $
    >> gdal-config --formats gxf gtiff hfa aigrid aaigrid ceos ceos2
    >> iso8211 bsb xpm sdts raw dted mem jdem envisat elas fit vrt
    >> usgsdem l1b nitf bmp hdf4 gif jpeg png grass

    Frank> This sounds like a bug in the GDAL 1.1.8 release with the
    Frank> GeoTIFF driver.  When it creates a new TIFF file with the
    Frank> Create() method instead of the CreateCopy() method it fails
    Frank> to write the coordinate system information out.  This bug
    Frank> was fixed a month or so after the GDAL 1.1.8 release.  I
    Frank> would encourage you to upgrade to the CVS snapshot code and
    Frank> perhaps even try using gdalwarptest which works similarly
    Frank> but uses a new more flexible algorithm.

Installed cvs snapshot of gdal and libgeotiff 1.2.1 and it all seems
to work. Thanks for everyone's help
Rob