Georeferencement of PointCloud

[bernarde]

Hi all,

I am testing ODM since few days and more than happy with the quality of the pointcloud it produce (Orthophoto are cool especially the performance but my main subject requires pointclouds).
Here his my setup :

• Working on Windows 10 Pro x64
• Installed Native ODM in C:\ODM
• My set of pictures is here : https://drive.google.com/drive/folders/10RFMUQwaAUIvdRzj1utt1gWbeV0Vcp-r
• My geo.txt file is at the same place, the target coordinate système is EPSG:2154 aka Lambert-93
• Command line used : .\run.bat C:_Test_ODM\100_0279\ --max-concurrency 8 --time --dem-resolution 100 --orthophoto-resolution 100 --dem-decimation 100 --geo C:_Test_ODM\100_0279\geo.txt --end-with odm_georeferencing

My issue is that I would like to georeference the point cloud in the EPSG:2154 system but the global offset of the point cloud end up being (-354758.00;-4865538.00;0.00) whereas the mean coordinates of my pictures is are (1036375,005;6323331,819;411,871).

Did I misunderstood the purpose of the geo.txt file or how to fill it ? Or is there another problem that I do not see ?

Thank you in advance for your help and do not hesitate to ask me more details.

[pierotofy]

Outputs are always in UTM, regardless of your geo.txt file.

You can always reproject the outputs afterward:

 pdal translate reprojection -i c:\path\to\odm_georeferenced_model.laz -o c:\path\to\reprojected.laz --filters.reprojection.out_srs="EPSG:2154"

[bernarde]

Thank you for your quick answer.

So it was indeed a huge misunderstanding of what is the use of the geo.txt file.

Re-reading the page https://docs.opendronemap.org/geo.html

By default ODM will use the GPS information embedded in the images, if it is available. Sometimes images do not contain GPS information, or a user wishes to override the information with more accurate data (such as RTK).

My pictures are taken by a RTK drone and as such embedded RTK pos and precision in the XMP tag does it count as being inside the EXIFF and so I do not need to supply a geo.txt file ?

And one more thing, I tried using pdal in console from “ODM\SuperBuild\install\bin” but the exe remain silent and noes not produce output so I had to install it with conda. Is there a way to use it directly from de install folder of ODM ?

Thank you again

[pierotofy]

@bernarde

Is there a way to use it directly from de install folder of ODM ?

Yes just run the “ODM Console” (console.bat) program. You can use PDAL directly from there.

@bernarde

so I do not need to supply a geo.txt file ?

I’d say probably not.

Cheers!

[bernarde]

Thank you again for your quick answer.

So based on your answer

@pierotofy

Yes just run the “ODM Console” (console.bat) program. You can use PDAL directly from there.

I looked into console.bat and win32env.bat to extract the minimum lines of the script that are required to run pdal.

Here is my solution :

set PATH= c:\path\to\ODM\venv\Lib\site-packages\osgeo;%PATH%
set PATH=C:\path\to\ODM\SuperBuild\install\bin;%PATH%
set PROJ_LIB=C:\path\to\ODM\venv\Lib\site-packages\osgeo\data\proj\

and then I can call the following line to reproject to my target coordinate system because Outputs of ODM are always UTM :

pdal translate reprojection -i c:\path\to\odm_georeferenced_model.laz -o c:\path\to\reprojected.laz --filters.reprojection.out_srs="EPSG:2154"

[smathermather]

Looks great!