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<p class=MsoNormal>Good day!<br>
<br>
I have a GDALDataset that I create from an image. I’ve used one of
the projection strings that the QGIS Projection Dialog returns, to set the
projection definition of this dataset. I also used the
QgsCoordinateReferenceSystem class to convert the string to Wkt format, in
order to assign the projection to the image.<o:p></o:p></p>
<p class=MsoNormal><br>
Used: "+proj=aea +lat_1=-18 +lat_2=-36 +lat_0=0 +lon_0=132 +x_0=0 +y_0=0
+ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs"<br>
<br>
After this has been done successfully, I now want to create a QgsCoordinateReferenceSystem
object from the assigned projection definition as follows:<br>
<br>
<o:p></o:p></p>
<p class=MsoNormal style='text-indent:.5in'><i>GDALDataset *dataset = theDataset;<o:p></o:p></i></p>
<p class=MsoNormal style='text-indent:.5in'><i> QgsCoordinateReferenceSystem
*crs = new QgsCoordinateReferenceSystem();<o:p></o:p></i></p>
<p class=MsoNormal><i> QString
projDefinition = dataset->GetProjectionRef();<o:p></o:p></i></p>
<p class=MsoNormal><i> if(crs->createFromWkt(projDefinition))<o:p></o:p></i></p>
<p class=MsoNormal><i> {<o:p></o:p></i></p>
<p class=MsoNormal><i> return
crs->projectionAcronym();<o:p></o:p></i></p>
<p class=MsoNormal><i> }else<o:p></o:p></i></p>
<p class=MsoNormal><i> {<o:p></o:p></i></p>
<p class=MsoNormal><i> return
"NOT FOUND";<o:p></o:p></i></p>
<p class=MsoNormal><i> }</i><br>
<br>
The projDefinition variable above receives the correct definition string:<br>
<i>PROJCS["unnamed",GEOGCS["Unknown datum based upon the GRS
1980 ellipsoid",DATUM["Not specified (based on GRS 1980
spheroid)",SPHEROID["GRS
1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433]],PROJECTION["Albers_Conic_Equal_Area"],PARAMETER["standard_parallel_1",-18],PARAMETER["standard_parallel_2",-36],PARAMETER["latitude_of_center",0],PARAMETER["longitude_of_center",132],PARAMETER["false_easting",0],PARAMETER["false_northing",0]]<o:p></o:p></i></p>
<p class=MsoNormal><i><o:p> </o:p></i></p>
<p class=MsoNormal>But for some reason, the
crs->createFromWkt(projDefinition) returns false every time.<br>
Does anyone know what may be wrong?<br>
<br>
Thank you!<br>
Francois<o:p></o:p></p>
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