[GRASSLIST:1829] inverse r.composite?
Ian Macmillan
ian_macmillan at umail.ucsb.edu
Wed Nov 19 21:23:52 EST 2003
Hi all, sorry to pester the list recently, but the more I try new things (I love
GRASS), the more questions I have (not a bad thing). I have been working on
using i.ortho.photo lately. Got all the bugs worked out with that (see earlier
posts).
Now I have a color orthorectified air photo in a UTM projection. I would like
to project this color raster into a lat-long location. Problem is that r.proj
seems to mess with the colors, and the newly projected air photo in the lat
long location has screwy colors (like a color ramp). I can't figure out how to
get around this. When I imported the original photo into my xy location, it
came in as a single rgb raster (both with r.in.tiff, and r.in.gdal). Going
through i.ortho.photo kept the colors the same in the UTM location. However
now the colors are scewball in the lat-long location. I figured a fix would be
to separate the color orthophoto into 3 bands (ortho_photo.r, ortho_photo.g,
ortho_photo.b), sort of like r.composite, but in reverse. I could then r.proj
each of those into the lat-long location, and composite them later. I can't
figure out how to do this though. Any ideas? Is there another approach? A
search through the archives unfortunately didn't help too much.
Thanks a million, Ian
More information about the grass-user
mailing list