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I have created two georeferenced orthomosaics using dronemade images. I used OpenDroneMap and Pix4D for that and I used the same source images for both.

I thought that if I used the same images, the results should overlap perfectly since the exact same source has been used. The problem now is that the Pix4D generated result seems to be shifted a little to the left and I don't know why that is.

The following images show what I mean:

This is the ODM result, which alines perfectly with the Google satellite basemap.

ODM_result

This here is the Pix4D generated result and it doesn't align at all, it is shifted.

enter image description here

The reference systems of both orthomosaics is : EPSG:32632 - WGS 84 / UTM zone 32N

The used .tiff files can be found on my DropBox: https://www.dropbox.com/sh/tcoo03aqqflx5ht/AAC-emzFz7z0Ne1P9FY0LVc-a?dl=0

I am pretty new to GIS.

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    Could post the quality report generated by Pix4D on DropBox ? Otherwise it's hard to tell : since Pix4D is closed-source, it might be possible to tell what went wrong or not just looking at generated outputs. On the other-hand, OpenDroneMap is open-source : even in case of bug/bad result, anyone can help and fix the issue (or at least explain what went wrong). My advice : stick with using OpenDroneMap (as it seems to produce more accurate results than Pix4D). – sfm-man Sep 20 '18 at 7:11
  • I would recommend you set up enough GCP's in both software packages. I know that Pix4D allows for that in a pretty straight forward way -for instance following this tutorial. For OpenDroneMap the documentation is a little bit more scarce but without too much searching I got here. I presume each of them is relying on different algorithms, but adding enough GCP's will definitely make the results comparable. Good luck! – Roberto Zeeland Sep 20 '18 at 7:30
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I would recommend you set up enough GCP's in both software packages. I know that Pix4D allows for that in a pretty straight forward way -for instance following this tutorial. For OpenDroneMap the documentation is a little bit more scarce but without too much searching I got here. I presume each of them is relying on different algorithms, but adding enough GCP's will definitely make the results comparable.

  • Adding sufficient Ground Control Points is the correct way. At the same time, the Questioner may wish to know that - Google's Satellite Imagery is NOT truly orthorectified for many areas. – Ralph Tee Jan 5 at 5:23

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