Yes, once you have specified GCPs with the -gcp option, you remove the
original georeferencing made of the origin coordinates and pixel size.
Several notes :
- There is an exclusive test in gdal_translate.cpp that prevents you from
setting both both GCPs and (origin coordinates, pixel size) at t
Jan,
I stepped through your procedure with a Canadian topo map to slightly adjust
its positioning, using GDAL 1.6.0:
1. Warp raster image of topo map to a projected coordinate system
No Need. Canadian topos already are georeferenced so I simply downloaded
http://ftp2.cits.rncan.gc.ca/pub/canm
Yes exactly! Brent highlights a point I never mentioned, and that may be
the source of the confusion: when I add control points to an already
georeferenced image, I gdalwarp it with the -tps option: a thin spline
transformer, that transforms the control points to the exact
georeferenced positio
