How to use "ground control points" now?

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Hi there,

I spent my time with “go map!” app and added some streetlights and manholes to get familiar with things. (adding manholes is also something for osm.to, but for later).

In the meantime, the Imaginata[0] in Jena replied to be interested to have our OSM.to QR-coded ground control points. They asked to have a “some fool-proof How-to-guide”[1], so this is what i would like to ask you:

could we discuss how to set up such a gcp? I would present our way and please give feedback what you think or how you would do it.

The following is based on the “flow plan” that is on [1]:

  • select a location where the qr-code gcp shall be constructed
  • in OpenStreetMap, create a new area for the above location (in size). create it, get the ID (I would say the way ID[2], if there is a better one, suggest it :))
  • with this ID, the QR-code can be generated with this as a possible “payload” https:// osm.to /w/502803011 . This is one of the ways our OSM.to can encode it for further things
  • painting, tiling, planting … the qr-code on the location
  • measuring the location of the 3 reference points of the QR-code with a GPS to have it really precise. Those are needed for the GCP references.
  • going back to OpenStreetMap to the node/way/etc that was created and then adding the newly established data
    • ground_control_point: minimum
      • standard: (like our osm.to or something else)
      • code type: (qr-code, etc…)
      • reference point(s): if qr-code, the 3 reference points (but minimum the one one in the corner)
    • extra
      • tile size (is important for satellites and drones from which height it can be seen with the used camera)
      • colour (black & white, white & black, etc…)
      • calibration_target: yes/no
      • owner: osm.to, space-agency, federal mapping services, etc…

The thing is, that once the the QR-code is painted, it cannot be changed (easily). So if it refers to an OSM node, the node needs to have all the information for this real-world object. The presented order reflects that.
It does not need to be a way id, it can be a node or area, our OSM.to can also use other IDs (see [1]).

So, what do you think? For me it is more a question how to handle the meta-data in the object. A GCP can be a calibration point (for geo refercing, or for the instrument). A calibration point is not always able to reference the location and only does calibration of the instruments for eg satellites.
Can’t we just prepare a template for all meta data one could set up that is usefull? (I hav seen this in “go map!” where I could easily place “vending machines” and then add more informations like “does it use coins?” or “is it inside a building”. So a preset of standard data.

What do you think?

[0] https://twitter.com/imaginata/status/1555959384227946504
[1] https://2021.spaceappschallenge.org/challenges/statements/drones-and-satellites-for-urban-development/teams/osmto/project
[2] OSM…/way/502803011

Andreas