Dear all,
Am I missing something simple here?
I am trying to import some rectified map scans (I do not wish to go
through the whole rectification process again if I can avoid it). They
were rectified in ArcMap. This produces associated aux, rrd and tfw
files.
Using gdal I was able to import the tifs without any coordinate system
but running the GRASS image rectify routines produced an extraordinary
small output window which I could not read with sufficient accuracy
(perhaps my eyes are too old?) - as I zoom in I lose the sight of the
map grid lines!
Any help or suggestions would be appreciated.It is possible I have
missed some obvious online help so feel free to be critical!
Best wishes
Darrel
Prof Darrel Maddy
Chair of Quaternary Sciences
University of Newcastle
http://www.ncl.ac.uk/geps/staff/profile/darrel.maddy
Hi,
from my experience:
ArcMap 8.x series has some bug - I was unable to change wrong central meridian
for with ArcMap georeferenced files (tiffs). Best solution was to remove
coordinate system from tiffs with ArcCatalog. Resulting file had correct
extent, but lacked coordinate system info. You can identify such case with
gdalinfo tool (see below example).
If You have such file, You can import into GRASS with "r.in.gdal -o" and image
will be in correct position IF locations coordinate system is same as for
tifs.
Hope this helps a little.
Maris.
________________________________________________________________
$ gdalinfo 4324-25.tif
Driver: GTiff/GeoTIFF
Size is 5000, 5000
Coordinate System is `'
Origin = (595000.000000,6335000.000000)
Pixel Size = (1.00000000,-1.00000000)
Corner Coordinates:
Upper Left ( 595000.000, 6335000.000)
Lower Left ( 595000.000, 6330000.000)
Upper Right ( 600000.000, 6335000.000)
Lower Right ( 600000.000, 6330000.000)
Center ( 597500.000, 6332500.000)
Band 1 Block=5000x1 Type=Byte, ColorInterp=Gray
On Monday 03 July 2006 19:10, Prof Darrel Maddy wrote:
They
were rectified in ArcMap. This produces associated aux, rrd and tfw
files.
Using gdal I was able to import the tifs without any coordinate system