GCP definition [Aerial]

• The workspace of the Ground Control Points page is organized as follow:

  

1. Top bar: the main menus of the X-Photo Processing manager.

2. Photos list: The complete list of the imported photos, with the indication of the GCPs it includes:

   

The photos can be filtered by GCP

3. Zoom-in: of the selected Photo, with the GCP locations.

To Show the tie points used, select

• GCP view: the GCPs can be visualized in 2 views.

  • Map view, by clicking on

    

  • Graphic view, by clicking on

    

5. GCPs list: with the coordinate differences.

   • The map visualization can be linked to the selected GCP from the list, by clicking on

   • If needed, markers can be deleted, either by deleting:

     • the last know marker, by selecting from the Delete Markers function.

     • or all the markers and redefine them from scratch, by selecting

Defining the ground control points

• To start the GCP definition process, click on

• In this step, we have to manually define at least three GCP:

  • by holding CTRL and press left button to add a GCP marker.

    

  • Or right button and select the GCP from the list to mark it as a known GCP.

    

Once you manually define at least three GCP, the remaining targets could be automatically recognized.

• We can drag the selection to the center of the target to define it.

  

• Once you’re satisfied with these first results, you can proceed to the next step.