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Re: [udig-devel] Problem with recognizing geotiff tags - I think
I am aware that the Geotools Geotiff reader doesn't get certain tags. Amr, a refractions employee found a Geotiff that GDal can read but Geotools doesn't recognize as a geotiff because it can't read the extent or crs. It is possible that it is a particular tag in the geotiff that is causing problems. 

Add a bug report in Geotools and attache a small sample image.

Jesse


On 22-Nov-07, at 11:22 AM, Adrian Custer wrote:


Hey,
Jody's running ahead with solutions but I don't yet understand what your issue is. You say the coordinates are NE which presumably means northing 
and easting which sounds perfect for a UTM. Long/Lat would be wrong.
UDig is showing your CRS is WGS84 which is what your output also claims 

What are you getting and what are you expecting?

--adrian



On Thu, 2007-11-22 at 10:31 -0800, Hugh Jennings wrote:

Hi,
Just want to know if this is a known problem or an incompatibility with 
some other software we use.
I can display geotiff's we have created but the geotiff tags don't seem 
to be read completely.

The image is in WGS UTM Zone 39.  Below is the result from listgeo

   listgeo uae_50m_dem_csh.tif
   Geotiff_Information:
      Version: 1
      Key_Revision: 1.0
      Tagged_Information:
         ModelTiepointTag (2,3):
            0                0                0
            623250           2702250          0
         ModelPixelScaleTag (1,3):
            50               50               0
         End_Of_Tags.
      Keyed_Information:
         GTModelTypeGeoKey (Short,1): ModelTypeProjected
         GTRasterTypeGeoKey (Short,1): RasterPixelIsArea
         GTCitationGeoKey (Ascii,257): "IMAGINE GeoTIFF Support
   Copyright 1991 - 2005 by Leica Geosystems Geospatial Imaging, LLC.
   All Rights Reserved
   @(#)$RCSfile: egtf.c $ IMAGINE 9.0 $Revision: 10.0 $ $Date:
   2005/07/26 15:10:00 EST $
   Projection Name = UTM
   Units = meters
   GeoTIFF Units = meters"
         GeogGeodeticDatumGeoKey (Short,1): Datum_WGS84
         GeogEllipsoidGeoKey (Short,1): Ellipse_WGS_84
         ProjectedCSTypeGeoKey (Short,1): PCS_WGS84_UTM_zone_39N
         PCSCitationGeoKey (Ascii,27): "Processed by Photosat LTD."
         ProjCoordTransGeoKey (Short,1): CT_TransverseMercator
         ProjLinearUnitsGeoKey (Short,1): Linear_Meter
         ProjNatOriginLongGeoKey (Double,1): 51
         ProjNatOriginLatGeoKey (Double,1): 0
         ProjFalseEastingGeoKey (Double,1): 500000
         ProjFalseNorthingGeoKey (Double,1): 0
         ProjScaleAtNatOriginGeoKey (Double,1): 0.9996
         End_Of_Keys.
      End_Of_Geotiff.

   PCS = 32639 (name unknown)
   Projection = 16039 ()
   Projection Method: CT_TransverseMercator
      ProjNatOriginLatGeoKey: 0.000000 (  0d 0' 0.00"N)
      ProjNatOriginLongGeoKey: 51.000000 ( 51d 0' 0.00"E)
      ProjScaleAtNatOriginGeoKey: 0.999600
      ProjFalseEastingGeoKey: 500000.000000
      ProjFalseNorthingGeoKey: 0.000000
   GCS: 4326/WGS 84
   Datum: 6326/World Geodetic System 1984
   Ellipsoid: 7030/WGS 84 (6378137.00,6356752.31)
   Prime Meridian: 8901/Greenwich (0.000000/  0d 0' 0.00"E)
   Projection Linear Units: 9001/metre (1.000000m)

   Corner Coordinates:
   Upper Left    ( 623250.000,2702250.000)
   Lower Left    ( 623250.000,2511800.000)
   Upper Right   ( 847450.000,2702250.000)
   Lower Right   ( 847450.000,2511800.000)
   Center        ( 735350.000,2607025.000)
When I load this image into a uDig map the CRS indicated is WGS84 with 
no projection.
The coordinates reported in the map window are EN and not Lat Long.

Is uDig attempting to reproject the image on the fly?

Do our geotiff's need some further tag to be recognized properly?

Any help would be appreciated,

Thanks,

Hugh


_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel


_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel

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