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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi all, <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I have found some GeoTIFF files for which a PCS or GCS
cannot be found if the information contained in the citation keys aren’t
processed.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The first kind of information that I’ve found packed
in the citation key PCSCitationGeoKey is the coordinate transformation method. As
an example, the keys below have been found in some GeoTIFF file I got. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GTModelTypeGeoKey (Short,1):
ModelTypeProjected<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GTRasterTypeGeoKey (Short,1):
RasterPixelIsArea<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeographicTypeGeoKey
(Short,1): Unknown-32768<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogGeodeticDatumGeoKey
(Short,1): Datum_WGS84<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogEllipsoidGeoKey
(Short,1): Ellipse_WGS_84<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjectedCSTypeGeoKey
(Short,1): User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> PCSCitationGeoKey (Ascii,47):
"Space Oblique Mercator-preset satellites WGS84"<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjectionGeoKey (Short,1):
User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjCoordTransGeoKey
(Short,1): User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjLinearUnitsGeoKey
(Short,1): Linear_Meter<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjNatOriginLongGeoKey
(Double,1): 76.7733936 <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjNatOriginLatGeoKey
(Double,1): 0 <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The second kind of information that I’ve found packed
in the citation key GeogCitationGeoKey is the datum and ellipsoid names. As an
example, the keys below have been found in some GeoTIFF file I got. Note that in
this example, there is also other relevant information in the other citation
keys, but these information are already in other non citation GeoTIFF keys.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>GTModelTypeGeoKey (Short,1): ModelTypeProjected<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GTRasterTypeGeoKey (Short,1):
RasterPixelIsArea<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GTCitationGeoKey (Ascii,274):
"IMAGINE GeoTIFF Support\nCopyright 1991 - 2005 by Leica Geosystems
Geospatial Imaging, LLC. All Rights Reserved\n@(#)$RCSfile: egtf.c $ IMAGINE
9.0 $Revision: 10.0 $ $Date: 2005/07/26 15:10:00 EST $\nProjection Name =
NAD_1983_HARN_Albers\nUnits = meters\nGeoTIFF Units = meters"<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeographicTypeGeoKey
(Short,1): User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogCitationGeoKey
(Ascii,297): "IMAGINE GeoTIFF Support\nCopyright 1991 - 2005 by Leica
Geosystems Geospatial Imaging, LLC. All Rights Reserved\n@(#)$RCSfile: egtf.c $
IMAGINE 9.0 $Revision: 10.0 $ $Date: 2005/07/26 15:10:00 EST $\nUnable to match
Ellipsoid (Datum) to a GeographicTypeGeoKey value\nEllipsoid = GRS 1980\nDatum
= HARN"<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogGeodeticDatumGeoKey
(Short,1): User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogPrimeMeridianGeoKey
(Short,1): PM_Greenwich<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogLinearUnitsGeoKey
(Short,1): Linear_Meter<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogAngularUnitsGeoKey
(Short,1): Angular_Degree<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogEllipsoidGeoKey
(Short,1): User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogSemiMajorAxisGeoKey
(Double,1): 6378137 <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> GeogSemiMinorAxisGeoKey
(Double,1): 6356752.31 <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjectedCSTypeGeoKey
(Short,1): User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> PCSCitationGeoKey (Ascii,236):
"IMAGINE GeoTIFF Support\nCopyright 1991 - 2005 by Leica Geosystems
Geospatial Imaging, LLC. All Rights Reserved\n@(#)$RCSfile: egtf.c $ IMAGINE
9.0 $Revision: 10.0 $ $Date: 2005/07/26 15:10:00 EST $\nProjection = Albers
Conical Equal Area"<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjectionGeoKey (Short,1):
User-Defined<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjCoordTransGeoKey
(Short,1): CT_AlbersEqualArea<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjLinearUnitsGeoKey
(Short,1): Linear_Meter<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjStdParallel1GeoKey
(Double,1):
34
<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjStdParallel2GeoKey
(Double,1):
40.5 <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjNatOriginLatGeoKey
(Double,1):
0
<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjFalseEastingGeoKey
(Double,1):
0
<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjFalseNorthingGeoKey
(Double,1): -4000000 <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> ProjCenterLongGeoKey
(Double,1): -120 <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>As I understand, to use of the citation keys to store
essential information is a mean to cope with the limitation of the GeoTIFF
standard.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>So are some of you aware of some non-official standard or
accepted practice regarding the storing of information in citation keys?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks, <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Mathieu<o:p></o:p></span></font></p>
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