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I'm a master planner and I want to use QGIS for, among others, importing images (jpg, png, etc without any georeferences). These images will mostly be screenshots of existing structures in Google Earth.

Now when I import such an image the scale and location are far off to what and where I want it. Does anyone know a good method to insert the image on the wanted location on the OSM base layer, translate, rotate and proportionally scale it?

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4

Since your images are without any georeferences, you can use this QGIS plugin named: Freehand raster georeferencer

In QGIS, open the "Plugins" > "Manage and install plugin" dialog. Install the "Freehand raster georeferencer" plugin.

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After installing it, its icons should be added to your tool bar.

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If you don't see the icons on your tool bar, go to Raster >> Freehand Raster Georeferencer

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Use the button labeled with "AD" to add your raster images, move them using "MO", rotate using "RO", scale using "SC", etc. The plugin works on both QGIS version 2 and 3, see more about using it on the plugin page.

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  • Worked great for my purposes, but just as a heads up, the "2P" function to georeference an image by two points appears to be broken in QGIS 3.8. – lucas Oct 31 '19 at 20:06
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The world file format is the way to spatial reference images. This file usually has the same name as you raster file but use another extension (*.w, *.wld or *.jgw, *.pgw etc). This is a text file with 6 lines:

20.0000000000000 A
0.00000000000000 B
0.00000000000000 C
-20.000000000000 D
424178.117       E
4313415.907      F

This values correspondent to formula:

x1 = Ax + Сy + E
y1 = Dx + By + F

A and D is pixel size in your Spatial Reference values (meters, degrees, etc)

E and F are upper left corner coordinates of your image

B and C - rotation

QGIS accepts this format (don't forget *.prj file with your projection WKT)

Some details is here: https://en.wikipedia.org/wiki/World_file

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2

There are some cases we cannot easily create reliable GCPs (ground control points) to georeference our image onto target layer.

I usually use Freehand raster georeferencer to interactively insert such images on my map.

It works like adding an Image Overlay on GoogleEarth.

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  • 1
    Thanks, I already tried this plugin. For me the large downside of the plugin is that you cannot scale proportionally and therefore mess up the image. I am looking for such a tool though, since georeferencing (as described in the earlier anwers) is a bit too much into detail for my specific use of qgis. – Mr. Steve Sep 19 '17 at 11:05

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