[GRASS-user] exporting as GTiff

[Stuart Edwards]

Hi

I am running into some problems exporting raster files as GTiffs.   
These are maps that were acquired as tiff images and georeferenced in  
GRASS.  When I export them the following dialog occurs:

"Writing format: GTiff
Writing type:   UInt16
Input file size is 18310, 7565
0Warning 1: Lost metadata writing to GeoTIFF ... too large to fit in  
tag.
...10...20...30...40...50...60...70...80...90...Warning 1: Lost  
metadata writing to GeoTIFF ... too large to fit in tag.
100 - done."

The metadata was created in GRASS so that message is puzzling.

The resulting file can actually be reimported into the location where  
it was created:

"A datum name wgs84 (WGS_1984) was specified without transformation  
parameters.
Note that the GRASS default for wgs84 is towgs84=0.000,0.000,0.000.
Projection of input dataset and current location appear to match.
Proceeding with import...


CREATING SUPPORT FILES FOR gtifftest
COPYING COLOR TABLE FOR gtifftest"

So how does that work?  I assume that importing it into another  
location would not, and I would not expect it to.

Also, is there a man page or some guidance on selecting the file type  
-- if it wasn't for the GIS.m output dialog I would not have known to  
use UInt16 and that this is the only format to support a color  
table.  The createopt and metaopt are similarly cryptic and not  
mentioned on the help page.  If this is covered in the gdal  
documentation, maybe a link on the GRASS help page would take care of  
it.

Thanks for any help

Stuart