why GTiff cann't write the geo. information.

[wjimage@…]

I use gdal1.2.3 to duplicate geo. information for geotiff format,but it failed
(successed with HFA with the same program).And,the data of HFA file is upside 
down.

if( (strGeoRef = pSrcDataset->GetProjectionRef()) != NULL && strlen(strGeoRef)
>0 )
{
oErr = oSRS.SetProjection(strGeoRef);
		oErr = pDstDataset->SetProjection( strGeoRef );
		if( oErr == CE_Failure )
			rv = 5;
		tGeo = pDstDataset->GetProjectionRef();
	}

[warmerdam]

Hi,

I think I am going to need more information.  I gather you are writing
your own C++ program calling GDAL to duplicate the GeoTIFF file?  I think 
I would need a working sample program that demonstrates the problem in order
to be able to investigate it. 

Alternatively, if you can duplicate the problem with gdal_translate that would
be helpful.  

Lastly, I will likely need a smallish input file that demonstrates the 
problem. 

[warmerdam]

*** This bug has been marked as a duplicate of 621 ***

[wjimage@…]

I have tried the simplest code as following,and the input data is the 
sample "utm.tif",also,the geographical information cann't be written to the 
output file(the image data can) ,and the SetProjection return success
(actually,the variable in geotiff.c is duplicate correctly),but the 
information doesn't  write into the file! I don't know the reason.


#include "gdal_priv.h"
#include "gdal.h"
#include "cpl_string.h"
#include "ogr_spatialref.h"

int main()
{
    GDALDataset  *poSrcDataset,*poDstDataset;
    GDALRasterBand  *poSrcBand,*poDstBand;
    int BandNumber = 0,nXSize,nYSize;
    float *pafScanline;
    char *pszSrcFilename = "e:\\utm.tif";
    char *pszDstFilename = "e:\\utm_copy.tif";
    GDALAllRegister();
    poSrcDataset = (GDALDataset *) GDALOpen( pszSrcFilename, GA_ReadOnly );
    if( poSrcDataset == NULL )
        return 0;

    const char *pszFormat = "GTiff";
    GDALDriver *poDriver = (GDALDriver *)GDALGetDriverByName(pszFormat);
    if( poDriver == NULL )
        return 0;
    poSrcBand = poSrcDataset->GetRasterBand( 1 );
    nXSize = poSrcBand->GetXSize();
    nYSize = poSrcBand->GetYSize();	
    poDstDataset = poDriver->Create( pszDstFilename, nXSize, nYSize, 1,    
GDT_Byte,NULL );
    poDstBand = poDstDataset->GetRasterBand( 1 );
    pafScanline = (float *) CPLMalloc(sizeof(float)*nXSize);
    for( int RowLoop = 0; RowLoop<nYSize; RowLoop++ )
    {
	poSrcBand->RasterIO(    
GF_Read,0,RowLoop,nXSize,1,pafScanline,nXSize,1,GDT_Float32,0,0);
	poDstBand->RasterIO( 
GF_Write,0,RowLoop,nXSize,1,pafScanline,nXSize,1,GDT_Float32,0,0);
    }
    const char *strGeoRef = NULL;
    if( (strGeoRef = poSrcDataset->GetProjectionRef()) != NULL && strlen
(strGeoRef)>0 )
    poDstDataset->SetProjection( strGeoRef );
    CPLFree(pafScanline);
    GDALClose(poSrcDataset);
    GDALClose(poDstDataset);
    CPLFree(pszSrcFilename);
    CPLFree(pszDstFilename);
    return 1;
}

[warmerdam]

Wujun,

I have confirmed the problem you report, and determined that the projection
isn't getting written because there is no geotransform or GCPs on the target
file. The GeoTIFF driver had a quirk where it would not write the projection
definition if there wasn't also going to be valid georeferencing tags.  

I have removed this restriction in CVS, but what you really want to do is
also copy over the geotransform. 

Try adding a line like:

   double adfGeoTransform[6];

   if( poSrcDataset->GetGeoTransform( adfGeoTransform ) == CE_None )
     poDstDataset->SetGeoTransform( adfGeoTransform );



Best regards,