Peter Keller wrote:

What I'd like to be able to do is something like georeferencing images in a GIS. That is, having a base image I refer to, create a series of points on the base and another image of a different scale that correspond to the same places, and the new image will be adjusted to match. Is there a way to do this with GIMP?

Here's how I'd do it:

1) Start with the base image in GIMP.

2) Add a new transparent layer to hold the reference points, but do not merge the reference points into the base image.

3) Add the new image as a new layer.

4) Use the Free selection tool to select points which match the reference points on the layer added in step 2.

5) Cut the selection, and paste it into a new layer.

6) Subdivide the selection in the new layer into quadrangles.

7) Select each quadrangle in layer 6, cut it, and create a new layer.

8) Use the perspective tool to adjust the layer of each quadrangle so that the points at the corner match the corresponding reference point in the layer 2.

9) Merge each the layer of each quadrangle into [a copy of] the base image.

ns

On 12/26/2010 04:28 AM, Peter Keller wrote:

What I'd like to be able to do is something like georeferencing images in a GIS. That is, having a base image I refer to, create a series of points on the base and another image of a different scale that correspond to the same places, and the new image will be adjusted to match. Is there a way to do this with GIMP? I have not been able to find anything like this so far in looking around. Maybe I just don't know the correct terminology for GIMP.

What you want to do looks a lot like the "cage transform tool" in the current 2.7.

You can google it up. You'll find a quick demo video here:

I wonder if the morph plugin in the GAP package could do what you want.

--- On Sat, 12/25/10, Peter Keller wrote:

From: Peter Keller Subject: [Gimp-user] warp by points
To: gimp-user at lists.XCF.Berkeley.EDU Date: Saturday, December 25, 2010, 10:28 PM

What I'd like to be able to do is something like georeferencing images in a GIS.? That is, having a base image I refer to, create a series of points on the base and another image of a different scale that correspond to the same places, and the new image will be adjusted to match.? Is there a way to do this with GIMP?? I have not been able to find anything like this so far in looking around.? Maybe I just don't know the correct terminology for GIMP.

Thanks for your help- Peter

What I'd like to be able to do is something like georeferencing images in a GIS. That is, having a base image I refer to, create a series of points on the base and another image of a different scale that correspond to the same places, and the new image will be adjusted to match. Is there a way to do this with GIMP? I have not been able to find anything like this so far in looking around. Maybe I just don't know the correct terminology for GIMP.

Thanks for your help-
Peter

Not really any suggestions for gimp but it is cold and boring here in the UK so I ran out a small video using "Art of Illusion". How it would perform with your presumably large images I do not know. Anyway FWIW and only 4 mins long http://www.youtube.com/watch?v=WZpJ3dV6KkE

On Sat, Dec 25, 2010 at 9:28 PM, Peter Keller wrote:

What I'd like to be able to do is something like georeferencing images in a GIS.  That is, having a base image I refer to, create a series of points on the base and another image of a different scale that correspond to the same places, and the new image will be adjusted to match.  Is there a way to do this with GIMP?  I have not been able to find anything like this so far in looking around.  Maybe I just don't know the correct terminology for GIMP.

This plug-in aligns two layers based on two points in each layer: http://registry.gimp.org/node/18961

It's been some time since I messed with it - IIRC you may need to tweak the "register" line of the script before it will appear in the menu. There was some discussion here: http://registry.gimp.org/node/18412

HTH, Chris

Have you looked at Hugin? I know it is used for similar things:

http://wiki.openstreetmap.org/wiki/Vertical_Aerial_Photographs http://www.mail-archive.com/hugin-ptx@googlegroups.com/msg11990.html

and a more generic tutorial for hugin: http://hugin.sourceforge.net/tutorials/Mosaic-mode/en.shtml

-Rob A>