I have downloaded some jpg files that came with jpgw cordinate information but when I bring the data into qgis using the Data Source Manager it doesn't ask me for the projection and it doesn't place the file in the correct spot.

I have tried to save the file as wld, jpw and jgw with no luck.

Examples can be downloaded from https://qimagery.information.qld.gov.au/ for free - The ones I tried were 1974 for Poruma island.

enter image description here

I am running QGIS version 3.10.1-A Coruña QGIS code revision ef24c526da

I tried the 'fixes' in What causes wrong placement of JPGs in QGIS 2.8.1? as well.

  • 2
    World files contain no projection information, only the 6 parameter affine transformation for cell to world. The correct world file for a jpg is jgw though it looks like you've tried that. What is the content of the world file? Is it really a world file and not a camera file? Being 1974 it's likely that the data is AGD66 or some other local datum as it predates WGS84 though it could be WGS72 epsg.io/4322 but I doubt that as WGS72 wasn't widely adopted in Australia. As a Queensland government dataset there should be some metadata available. – Michael Stimson Jan 28 '20 at 5:00

According to the QImagery help-page, you should try EPSG:3857 (Pseudo Mercator). enter image description here

In addition you must tell QGIS which CRS to use. From the top menu, choose Settings – Options and the CRS-tab. Choose e.g. the option "Prompt for CRS" when a layer is loaded that has no CRS (or "USe project CRS" if you have set the project CRS to be 3857 in beforehand). QGIS reads jgw- and jpgw-files. enter image description here As @Michael Stimson points out, the jpgw-file contains no projection information nor CRS (or EPGS-code). So you have to tell QGIS which CRS to use when adding the jpg-file.

The image appears in the right place - here shown with Google Terrain from the plugin QuickMapServices in QGIS 3.10.2.

enter image description here

  • Setting the options to prompt when CRS was unknown was the step I missed. Thanks. – GeorgeC Jan 28 '20 at 11:25

If you run gdalinfo you'll notise that GDAL does recognize .jpgw as a World file.

gdalinfo QAP27863800.JPG
Files: QAP27863800.JPG
Size is 3800, 4000
GeoTransform =
  15923663.02324857, 0.6464472699464198, 0.004029513396384988
  -1123438.005344422, 0.004072074029169209, -0.6506963195161204
  EXIF_DateTime=2010:02:18 13:09:37
  EXIF_Software=Adobe Photoshop CS3 Windows
Corner Coordinates:
Upper Left  (15923663.023,-1123438.005)
Lower Left  (15923679.141,-1126040.791)
Upper Right (15926119.523,-1123422.531)
Lower Right (15926135.641,-1126025.317)
Center      (15924899.332,-1124731.661)
Band 1 Block=3800x1 Type=Byte, ColorInterp=Gray
  Overviews: 1900x2000, 950x1000, 475x500
  Image Structure Metadata:

WGS84 coordinates of the location are about 143.03°E, -10.07°N. What remains is to find the right code for the coordinate reference system that is used in the .jpgw file.

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