Hello Markus Thanks for the reply To do what you suggest, I would have to retrieve LOCATION's CRS EPSG code and I'm not able to get it automatically. I only can get that PROJ4 string by using g.proj. Is there a way to automatically get a LOCATIONS's EPSG code? Best regards, Kim
2010/6/29 Markus Neteler <[email protected]> > On Tue, Jun 29, 2010 at 11:20 AM, Kim Besson <[email protected]> > wrote: > > Greetings > > A couple of days ago I have exchanged a few messages with Paul Kelly and > > Micha Silver regarding this issue. But now I have a new example and I > want > > to know if I'm doing anything wrong and better understand what is GRASS > > behaviour. > > I'm trying to have an aumatic procedure to reproject images using > gdalwarp. > > First it checks image CRS (g.proj input=IMAGE -jf) and compares with > > Location's CRS (g.proj -jf). > > As target_CRS I'm using the output from g.proj -j -f . > > In this case, g.proj -jf give me the Location«s CRS: > > +proj=utm +south +no_defs +zone=24 +a=6378137 +rf=298.257223563 > > +towgs84=0.000,0.000,0.000 +to_meter=1 > > (Sidenote. This Location was created based on an EPSG) > > I use this expression to warp the image: > > gdalwarp -t_srs "+proj=utm +south +no_defs +zone=24 +a=6378137 > > +rf=298.257223563 +towgs84=0.000,0.000,0.000 +to_meter=1" input.tif > > proj4.tif > > But if I check proj4.tif CRS I get this: > > +proj=utm +south +no_defs +zone=24 +a=6378137 +rf=298.257223563 > +to_meter=1 > > Trying to open with OGR... > > Trying to open with GDAL... > > ...succeeded. > > Datum <unknown> not recognised by GRASS and no parameters found > > Why towgs84 is not kept in the image? > > To my knowledge the GeoTIFF format is not able to keep the towgs84 string. > Did you try with different formats? > > But in general, it may be better to assign proj metadata via EPSG code. > > Markus >
_______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
