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<DIV><FONT face=Arial size=2>Hello!</FONT></DIV>
<DIV><FONT face=Arial size=2>I'm trying to use imagery tools to
georeference/rectify an image taken from google earth...</FONT></DIV>
<DIV><FONT face=Arial size=2>Here's the procedure I've used without
success:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>- From GEarth saved image to a local file (jpeg)
(</FONT><FONT face=Arial size=2> I've tried to convert this jpeg to png but
this didn't helped me. In both case I've keeped the image as 24
bit...)</FONT></DIV>
<DIV><FONT face=Arial size=2>- Created a location wgs84 utm29 (North!) with
region coordinate taken from GEarth (in local format)</FONT></DIV>
<DIV><FONT face=Arial size=2>- Created a location xy in grass (6.2.3) with
region as big as the picture</FONT></DIV>
<DIV><FONT face=Arial size=2>- Imported the image with g.in.gdal: this creates 3
raster maps, blue green and red</FONT></DIV>
<DIV><FONT face=Arial size=2>- r.composite the 3 rasters to one "gearth"
raster</FONT></DIV>
<DIV><FONT face=Arial size=2>- i.group to create group "group" containing the
gearth raster</FONT></DIV>
<DIV><FONT face=Arial size=2>- i.target giving target the wgs84 utm29 location
(mapset user)</FONT></DIV>
<DIV><FONT face=Arial size=2>- i.points to give 3 GCPs</FONT></DIV>
<DIV><FONT face=Arial size=2>(- tried also to run i.group to remove the
gearth raster from r.composite and add the 3 rgb rasters map)</FONT></DIV>
<DIV><FONT face=Arial size=2>- i.rectify -a group=group input=group
extension=_rect order=1</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Everything goes fine till here, except for the fact
that if I add the -c option to i.rectify it will always fail with "error while
writing to temp file".</FONT></DIV>
<DIV><FONT face=Arial size=2>However, when I go to other location the map
doesn't display.</FONT></DIV>
<DIV><FONT face=Arial size=2>If I've rectified the 3 rgb rasters I can try to
display the map with an RGB layer or creating a single raster map with
r.composite but, first of all, it takes forever (running "top" while doing this
displayed a 99% of CPU use by d.rgb or r.composite) and, last but not last, the
map doesn't display. If I select on the map display "zoom to selected map" it
will zoom to default region (the selected region in this location) even if I
used i.rectify without the -c flag!</FONT></DIV>
<DIV><FONT face=Arial size=2>Worster if I try to rectify the "r.composite"d
raster (the one containing the 3 imported channel) first and then rectify
it. Everything goes ok but if I try to display it grass just stuck and I need to
restart the x server to quit the grass windows...</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I had a look at the data in the wgs84_utm29
location and noticed that this last "r.composite"d raster hasn't been
"converted". Data in the cell directory is around 24 kb and there is a 148
kb file in the cell_misc/$RASTER_NAME directory .. starting jpeg was
a couple of MBs..</FONT></DIV>
<DIV><FONT face=Arial size=2>Stranger in the other case (rectifying the 3
channels and then displaying rgb layer or r.composite them): the files in the
cell directory are around 15 kb and 148 kb in the cell_misc folders, but after
r.composite, the raster coming from this has 6.9 MB in the cell folder and 107.3
MB in the cell_misc folder of data.</FONT></DIV>
<DIV><FONT face=Arial size=2>All the files I'm talking about in the cell misc
folder are called "null" and dolphin recognized them by the MIME type as
jpeg2000, but gwenview isn't able to display them...</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>My configuration is the installation of the GRASS
Live DVD coming from the Trento University in a VMWare machine running with
VMPlayer 2.0.5 on Debian Etch.</FONT></DIV>
<DIV><FONT face=Arial size=2>This live should be Kubuntu Hardy ( ?)
based.</FONT></DIV></BODY></HTML>