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Backstory: employer is GIS incapable and most of the data we work with doesnt play nice with GIS software. That said, we have a client who is very GIS oriented. My boss (not my work) is providing them with what are really just pictures of an environmental variable that he creates in photoshop. They are asking for the "world file" for the rasters so they can plug the images into their ESRI powered dataflow.

I have georeferenced the rasters before to make some overlays, but I believe they are currently referenced to NAD (it's the Gulf of Mexico-NAD worked).

I have seen some guide info online for generating world files, projection files, etc with QGIS but wanted to ask the community's opinion on how to make the simplest, most compatible solution? w

ould it be the '.wld' extension I've seen or do i need the projection '.prj' file?

Do I need to find out the clients projection since they are likely on a more global coordinate system than the NAD?

  • for reference: its a referenced tif, and the QGIS GDAL based 'extract projection' tool is failing without error (says its completed-no files created) – WClark97 Feb 23 '15 at 19:31
  • If it is georeferenced tif (geotif) then the information is stored in the tif header and no additional file should be needed. Otherwise you need a world file, a plain text file with the math description of the georeferencing. However different software may look for different extensions. In Arc, it's looking for tfw or tifw. I don't know if the internal format of a .wld is the same as a tfw. The .prj file is something different - that defines a projection. A defined project is needed to georeference, but the projection contains no georeferencing information (hope that makes sense). – Chris W Feb 23 '15 at 22:01
  • A comment on the accepted answer at this question seems to indicate a wld is the same as a tfw or jpw, but that it doesn't follow the naming convention (so renaming the extension might work). I can't speak to the extract projection tool failure. You may want to edit that into your question. Finding out the client's projection is just a matter of service. If they know what it's in, they can reproject it - just an extra step for them. I'd be more concerned about the implied accuracy (ie, it's not spatial data to start with, just a picture). – Chris W Feb 23 '15 at 22:05

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