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I have successfully georeferenced a raster file via the Georeferencer plugin (Georeferencer GDAL Version 3.1.9) in QGIS 1.7.0.

However, I noticed that the output georeferenced raster file is in TIFF format. Is there a way for me to change it to something like JPEG (or others) to save disk space and memory usage? Thanks.

BTW, I am running this in Mac OS X 10.6.7.

2 Answers 2

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Yes, after georeferencing, use the Raster > Translate tool (also called gdal_translate in GDAL's CLI) available in the GdalTools Plugin. I don't know if it is possible to select other raster formats within the Georeferencer plugin.

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  • I got the error "The process failed to start. Either the invoked program is missing, or you may have insufficient permissions to invoke the program.", what does that mean? Thanks.
    – hpy
    Apr 25, 2011 at 14:27
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    @penyuan: Is this related to the Raster > Translate process? You need to make sure that GDAL is installed and your GDAL Tools plugin is configured to use the GDAL binaries. The setting option is available at Raster > GDALTool Settings.
    – maning
    Apr 26, 2011 at 2:18
  • Yes that did it. The trick is to download and install the GDAL frameworks from the KyngChaos site and set the path per the installer's directions. Thanks!
    – hpy
    Apr 26, 2011 at 15:37
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i'm thinking JPEG (the common form) is not a file type which supports georeferenced metadata. You should be happy with TIFF. The other option is create a world file which goes with the image.

see raster in http://en.wikipedia.org/wiki/GIS_file_formats

Perhaps you are considering GeoTagging JPEG files to give them a location along a path?

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  • I would be OK with an associated world file, but how do I create one in QGIS to go with the georeferenced image? BTW, the "create world file" option is only available when I choose linear transformation, which is not what I want in this case. Thanks for your answer.
    – hpy
    Apr 25, 2011 at 14:21
  • A (rather cumbersome) way to create a world file in QGIS (if you already have a georeferenced raster) is to use the Georeferencer and choose Transformation type "Linear", and then make sure that "Create World File" is checked. But for some reason, first you must establish two GCPs. You can do this by adding the points, writing some random numbers in the Enter Map Coordinates box and then copying the srcX to dstX and the srcY to dstY. Jul 28, 2014 at 13:03
  • A better alternative for creating a world file for an already georeferenced raster is to use QGIS raster-> conversion-> translate and add the following option to gdal_translate: "-co worldfile=yes". Jul 28, 2014 at 13:16

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