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I've done a search and haven't found any recent threads regarding this.

Is it possible to georeference drone images using QGIS?

Ultimately I would like to import these photos into C3D

I look forward to trying to figure this out with everyone!

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  • C3D meaning Civil 3D (AutoCAD?)
    – Mapperz
    Jun 1, 2023 at 19:36
  • What format are your drone images? Normally Jpeg or tiff will have georeferenced info embedded.
    – Mapperz
    Jun 1, 2023 at 19:41
  • They are JPEG. I believe it has the GPS location but what gets tricky is the angle of the gimble etc.. Correct Civil 3D :)
    – Sylvino
    Jun 1, 2023 at 20:10
  • You may find the following question and answer helpful, as well as showing you some of the limitations of what can be done easily. gis.stackexchange.com/questions/384756/…
    – Houska
    Jun 1, 2023 at 21:50

3 Answers 3

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You certainly can georeference images with QGIS. See this tutorial.

From your comments about angles of the gimble I suspect you are asking if you can automatically georeference images in QGIS. That answer is no, you cannot. You can, in QGIS, create a photo-linked point at the location of image capture using built in tools or consider the ImportPhotos plugin. For adding auto-rotated images to QGIS based on EXIF data have a look at the Vertical Photo Placer plugin.

I have some algorithms for auto-georeferencing images. These tools are camera specific and quality varies with sensors and terrain. If this is what you are after you can send me a few images and I can test them.

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  • I’ve got the mini 3 pro do you think that your algorithms will work with it? My work computer blocks me from installing software so I don’t believe I can use vertical photo plugin as I need to install that exfiftool
    – Sylvino
    Jun 1, 2023 at 20:44
  • Yes, tested and working with the Mini Pro 3.
    – GBG
    Jun 1, 2023 at 22:03
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This is a complex topic and a perfect answer is difficult. Incremental steps in order of difficulty.

  1. The GPS locations of the camera are stored in EXIF tags, generally Exif.GPSInfo.GPSLongitude and ...GPSLatitude. These are in EPSG:4326. You can access these tags manually in photo editors, operating system file info, etc. You could also access them from QGIS using expressions (https://docs.qgis.org/latest/en/docs/user_manual/expressions/functions_list.html#exif) or PyQGIS (https://qgis.org/pyqgis/3.22/core/QgsExifTools.html#module-QgsExifTools). However, knowing the drone location of course doesn't mean you know exactly what the image is pointing at.

  2. If you know roughly where an image is, you can georeference it using the Georeferencer, manually picking points vs an existing map or georeferenced aerial orthophoto. See https://docs.qgis.org/latest/en/docs/user_manual/working_with_raster/georeferencer.html for instructions. This does not make use of any info stored in the drone photo, of course. If the terrain is flat, it should be enough to create 4 GCPs, ideally close-ish to the corners, and use the Projective transformation type.

  3. Some time ago, I pursued the seemingly tractable question of "Given drone lat, long, (relative) altitude; camera bearing, yaw, and focal length; what are the coordinates of a drone photo's corners?" See the question and discussion at Georeference single drone image from EXIF data. I think there is a workable approach there in the special case where terrain is flat, however there are challenges (camera focal length reporting and barrel distortion are two of them) even then. And accounting for nonflat terrain, especially within the image, would be more complicated.

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It is not a good idea to georeference distorted drone images in QGIS. Why don't you use an other open source software to generate true orthophoto from those images? For example OpenDroneMap or WebODM is a perfect tool for it.

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  • Zoltan makes a good point in that you could create a single ortho from the images using SfM software. This will work if and only if there is sufficient image overlap in your data set and there is sufficient correspondence in the data set.
    – GBG
    Nov 29, 2023 at 20:06

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