[gdal-dev] geotiff projection not showing up

[Frank Warmerdam]

Norman,

My apologies.  The GCP projection is actually supposed to be passed as the
third value in the SetGCPs call - where you have passed the string
"Richmond".  Instead pass the whole WKT strings for the coordinate system.

Best regards,
Frank


On Wed, Nov 6, 2013 at 4:00 PM, Norman Goldstein <normvcr at telus.net> wrote:

>  Frank,
>
> I am using GDAL
> Version     : 1.9.2
>
> so maybe that is why I do not see the method SetGCPProjection().
>
> I think you have convinced me, though, to calculate the 6 coefficients
> directly,
> and then call SetGeoTransform().  Will let you guys know how this works out
> for me.
>
> Thank you,
> Norm
>
>
>
> On 11/06/2013 01:51 PM, Frank Warmerdam wrote:
>
> Norman,
>
>  I believe you want to call SetGCPProjection() instead of SetProjection()
> when using GCPs instead of an affine transform.
>
>  Best regards,
> Frank
>
>
>
> On Wed, Nov 6, 2013 at 1:23 PM, Norman Goldstein <normvcr at telus.net>wrote:
>
>> I have created a geotiff file using the "GTiff" driver, and have
>> successfully set options for it to be a strips file with no compression.
>>  Also, successfully called the functions
>>
>> dataset->SetMetadataItem( "AREA_OR_POINT",
>>                                             "Point",
>>                                              nullptr ) )
>>
>> and
>>
>> dataset->SetGCPs( 3,
>>                                gcps,
>>                                "Richmond" )
>>
>> Here is the listgeo dump:
>>
>> ############# listgeo dump ##############
>> Geotiff_Information:
>>    Version: 1
>>    Key_Revision: 1.0
>>    Tagged_Information:
>>       ModelTiepointTag (6,3):
>>          0                249              0
>>          0                0                0
>>          399              249              0
>>          1000             0                0
>>          0                0                0
>>          0                2000             0
>>       End_Of_Tags.
>>    Keyed_Information:
>>       GTRasterTypeGeoKey (Short,1): RasterPixelIsPoint
>>       End_Of_Keys.
>>    End_Of_Geotiff.
>>
>>
>> Corner Coordinates:
>>  ... unable to transform points between pixel/line and PCS space
>> #####################################
>>
>> I also set the reference system using the following code:
>>
>> /////////////////////// c++ code ////////////////////////////
>>   OGRSpatialReference oSRS;
>>   oSRS.SetProjCS( "NoWhere" );
>>   oSRS.SetWellKnownGeogCS( "WGS84" );
>>   oSRS.SetEquirectangular( 0.0,        // Centre lat
>>                0.0,        // Centre lon
>>                0.0,   // False Easting
>>                0.0 ); // False Northing
>>
>>   char* wkt = nullptr;
>>
>>   if( OGRERR_NONE != oSRS.exportToPrettyWkt( &wkt ) )
>>   {
>>      error...
>>   }
>>
>>   if( CE_Failure == dataset->SetProjection( wkt ) )
>>   {
>>    error...
>>   }
>> ///////////////////////////////////////////////////////////////
>>
>> So, why is listgeo not able to transform points between pixel/line and
>> PCS space?
>>
>> I am happy to upload a full working example if needed.
>>
>> Thank you.
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> _______________________________________________
>> gdal-dev mailing list
>> gdal-dev at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>>
>
>
>
>  --
>
> ---------------------------------------+--------------------------------------
> I set the clouds in motion - turn up   | Frank Warmerdam,
> warmerdam at pobox.com
> light and sound - activate the windows | http://pobox.com/~warmerdam
> and watch the world go round - Rush    | Geospatial Software Developer
>
>
>
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>



-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam,
warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Software Developer
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20131107/1136102e/attachment.html>