Adding ground control points to raster in ArcGIS Pro desktop

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06-08-2022 12:06 AM
bobscarto
New Contributor II

I'm trying to add ground control points to an orthomosaic raster created in ArcGIS Pro desktop.  The orthomosaic was created with drone images taken with a non-ESRI mission app (Map Pilot Pro).  The orthomosaic has come out perfect, but I did six GCPs during the mission with the GCPs being targets on the site surface, which were then accurately located using a GPS/GNSS PPK device.  The targets are visible in the finished orthomosaic, and I've tried to use the Manage GCPs tool to accurately locate the GCPs for a final adjustment of the orthomosaic.  I have created a .csv file of the GCP coordinates according to the instructions, and imported it to the GCP Manager window. I've looked for a tutorial for what should follow, which to me would be identifying the individual GCPs on the raster and linking them to the GCP in the .csv file, but I can't seem to work this out. Can anyone help?

Cheers, Bob

4 Replies
JustinJohnston
Occasional Contributor II

Following myself.  I wasn’t even aware there was an ability to process images into orthomosaics in ArcGIS Pro, much less add ground control. ESRI Drone2Map does all of what you are indicating and more (process 3D models, .LAS files, DEM, etc.), but if you can actually get some of that out of ArcGIS Pro, even if a little more work, would be interesting as it saves a $1,500 license.  

cheers,

Justin

by Anonymous User
Not applicable

Maybe I'm thinking about this too simply, but couldn't you just georeference the ortho to the GCPs and apply the transformation? E.g. click on the GCP in the raster and then click on the corresponding vector point?

I'm not familiar with the image processing software OP mentioned, but as far as I know it is better to incorporate GCPs during ortho processing, and not after. If the software is working as intended, the GCP transformation will be better fit than a shift after the fact.

bobscarto
New Contributor II

Hi, thanks for the suggestion, but I'm unclear on the process.  I can click on the GCP in the raster, but don't understand 'click on the corresponding vector point'? (I'm still on the ArcGIS learning curve).  I agree with your second point, which I'm trying to achieve.  Cheers, Bob

by Anonymous User
Not applicable

If you have the GCP coordinates and their spatial reference, you can load them into ArcGIS as a point feature class. The orthomosaic is the "from", and the GCP point geometry is the "too" for georeferencing. Then you can use one of the georeferencing transforms to do the shift.