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I am trying to find a GIS software that does this, so I am trying QGIS but other suggestions are welcome.

I have a basic shp boundary such as a rectangle. I want to be able to import an unreferenced image (such as a tif or jpg) and place it as a new layer without needing to reference points immediately. I want to be able to use handles or another tool to re-size or stretch it in comparison to my shp. I realize this file is not necessarily referenced in this state even though it is floating over a referenced layer. It does not necessarily have to be saved as a referenced file ever as long as I can see it as an overlay while I work.

Basically because the image I am importing is not actual imagery and does not currently match anything on the map, I want to be able to place it in a way similar to placing and stretching an image in Microsoft Word.

Here's a sample image I photoshoped of what this feature might look like: enter image description here

Is there a way to do this in QGIS, or suggestions of other software?

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Stretching with handles (like in photoshop or illustrator) isn't a feature of any GIS software I know of. The best thing to do might be to match the four corners of your rectangle shapefile to the four corners of the image. This would be the same as stretching it till it matches the shapefile. – Taylor H. Feb 4 at 18:34
Thanks for the thoughts. I have an obsolete old piece of software called SSToolkit which was built off an old verison of ArcGIS. It did have a feature to overlay an image, but I cannot seem to find any newer software that does this. Thanks for your thoughts though. – user1098504 Feb 4 at 18:59
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You do realise that the size of the referenced layer on the screen depends on the scale/zoom level? From what you describe, making a screenshot of that layer and then doing the manipulation in gimp or other graphics app would be just as effective. – lynxlynxlynx Feb 4 at 21:41
Why do you want to do this in QGis? Even if you scale your image adequately still it can look quite shitty in the print composer. You do a little bit of GIMP magic and add your image afterwards to the printed map (save as png). – Curlew Feb 5 at 10:25
why not just add the image in the print composer stage??? – Gerald O'Reilly Feb 5 at 12:09

4 Answers

up vote 3 down vote accepted

I do this step in Google Earth. I make reference marks on the edge of the raster and match these with point markers which I then save as a kml and import into QGIS. From there I georeference.

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Thanks for the idea. That does seem to be my best option of anything I have found. For some specific uses some people like myself do need to bring in an image that does not have specific points associated with it. I appreciate the idea. – user1098504 Feb 5 at 12:07
up vote 1 down vote

As I see it, in QGIS you have two options:

  1. Georeference the image and you can use it in map view like any other raster layer.

  2. If you only need it for print. Add it in Print Composer for decoration purposes only.

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up vote 1 down vote

With the ArcMap Georeferencer you can use 'Fit To Display' to adjust an unreferenced raster layer to the current view without specifying reference points.I'm not sure you can save the position of the layer without actually adding actual reference points though.

If you want to use QGIS, maybe you could integrate Inkscape in the workflow? You could work with SVG vector layers that you either export from or import to QGIS and use the unreferenced image in Inkscape. Haven't tried it myself.

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You can use a combination of QGIS and FWTools. Within QGIS you will want to find the XY of each corner. These value will be used as input in FWTools (which is a command line tool). In FWTools you will want to use the gdal_translate command. There are many options in the gdal_translate command, you will will want to use the -a_srs and the -a_ullr functions at a minimum. The -a_srs function assigns the projection, while the -a_ullr function uses the XY coordinates to "assign the place" of the image. For example:

 gdal_translate -a_srs EPSG:26916 332800 5365600 332800 5365500 c:\temp\source.tif c:\temp\projected.tif
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