[GRASSLIST:3361] Re: orthorectification with DEM

[Markus Neteler]

On Thu, Mar 21, 2002 at 05:44:23PM -0800, Eric G. Miller wrote:
> On Thu, Mar 21, 2002 at 03:11:29PM -0500, Wouter Buytaert wrote:
> > 
> > Hello,
> > 
> > we have some satellite images that we would like to orthorectificate by 
> > means of a DEM and some georeference points. As it are mountain region 
> > images we believe that the differences in elevation are the main source 
> > of distortion; that's why we would like to use the DEM.
> > 
> > Is there some procedure in grass that can do this?
> 
> See the imagery tutorial (a bit out of date, but should cover the
> steps).

Mhhh - in fact there is i.ortho.photo (not covered there) to
ortho-rectify aerial images with camera data and DEM.
For *ortho*-rectification of satellite images there is i.points3 and
i.rectify3, both in alpha state (see experimental CVS [snapshot]).
The src/libes/image3/ library contains code for that.

Without programming efforts which are highly appreciated you may face
some problems.

Markus Neteler