GCP Import format

WebODM
#1

Hi @pierotofy,
My GCP file is exported as displayed in the attached image:
Can you let me know if I need to rearrange these values? The “Target Reference Frame” is WGS84 (G1762) current. Do I need to convert these points to a different reference frame? Also, does it automatically find these points or do I get an opportunity to match the points to the image once imported?
59%20AM

#2

I learned to rearrange the info and export as a .txt file. So the 12 GCP I have are successfully imported. The next step I need clarification on is locking the point. I’m confused how to select the GCP# for the correct shot / coordinate. What is the map for on the right? The satellite base-map from leaflet is very poor resolution. How do I set this to Google Maps or another high resolution option? When I copy the URL is doesn’t change anything. Also it wants a point locked in. Are my GCP supposed to be displayed here cause if so then the import of my .txt was unsuccessful. Support for this would be very helpful.

#3

Are you referring to the “GCP Editor” (https://demo.webodm.org/plugins/posm-gcpi/) ?

Map on the right is for placing GCPs on the map.

You can add a custom TMS url if you want to use higher resolution basemaps. See the “Map Provider” button in the top right of the map.

If you import an existing GCP file, the points should display in the map.

#4

The correct format for a partial GCP file that does not yet have associated images and image positions can be found here: https://github.com/OpenDroneMap/odm_data_copr/blob/master/gcp_list_noimg.txt

Using this format, you wouldn’t use the leaflet map at all, but the coordinates you collected in the field, and you simply associate them with the appropriate image and image position.

#5

I am having trouble getting the gcp_noimg file in webodm gcp interface to work.
When importing measured GCP points (rtk) to match with images, the interface will either:
a) not render the targets at all on the side map or;
b) the targets appear on the side map in nonsense coordinate locations ‘blue space’ which have no satellite or openstreetmap data associated with them

in terms of input files, I have tried:

  • lat long coords + headers: WGS84, EPSG and Proj4
  • UTM coords + headers: WGS84 UTM 51S, EPSG, Proj4

Any suggestions much welcomed.

#6

Managed to get this to run after trying ~25 different combinations.
Bizarrely the only header/data combination that would work was
Header: MGA (australian national grid) in proj4 format
Data: UTM format