[gdal-dev] Setting metadata in newly created NITF image via create options

[Ozy Sjahputera]

Folks,

I need to create a new NITF image and set some RPC parameters I grabbed 
from another NITF file. According to the online documentation 
(http://www.gdal.org/frmt_nitf.html):

 "Most file header, imagery header metadata and security fields can be 
set with appropriate *creation options* (although they are reported as 
metadata item, but must not be set as metadata)."

So I did the following:

1   char **create_options = NULL;
2   GDALDataset* ds = (GDALDataset*) GDALOpen( existing_nitf_file, 
GA_ReadOnly );
3   create_options = CSLSetNameValue( create_options, "RPC_LINE_OFF", 
ds->GetMetadataItem( "LINE_OFF", "RPC"  ) );
4   GDALDriver *driver = GetGDALDriverManager()->GetDriverByName("NITF");
5   GDALDataset* out_ds=  driver->Create( new_nitf_file, width, height, 
bandCount(), GDT_UInt16, create_options );

During execution, I am getting the following warning message:

Warning 6: Driver NITF does not support RPC_LINE_OFF creation option

I also tried using "LINE_OFF" in line 2 as the metadata key and still 
getting the same warning.

When I processed the newly created nitf file, calling 
GetMetadataItem("RPC_LINE_OFF",NULL) or GetMedataItem("LINE_OFF", "RPC") 
returns NULL. So the metadata was not set.

Did I misunderstood the documentation above that talks about setting 
imagery header metadata via create options?

I use GDAL v.1.6.3.

Thanks
Ozy