Manual ground control point (GCP) tagging can be used for any type of GCP target and does not require that processing is completed. If your data has been processed without GCPs, Site Scan can predict which photos are expected to show the GCP target that facilitate GCP tagging.
To manually tag in Site Scan, complete the following steps:
- After uploading the GCPs, in the 2D view of your mission, turn on the Ground Control Points layer and click Review GCPs on the toolbar.
- Click the GCP icon (checkerboard) to start tagging photos associated with the GCP. The GCP icon turns blue, and if the mission has been processed, images that potentially contain a ground target are also highlighted in blue.
- Select a photo near the GCP. A pop-up with the photo appears. Pan and zoom to find the GCP target. Click precisely as possible on the survey point.
- Click Save.
- Repeat steps 2 through 4 until you have tagged 5 to 8 photos for each GCP. The minimum number of photos that must be tagged for a GCP to be used is 3.
- When finished, click Next.
- If you want to use checkpoints, click the GCPs you want to designate as checkpoints, then click Confirm. If you are not using checkpoints, don't select any GCPs, then click Confirm to process your data. Any points designated as checkpoints will be used for accuracy assessment only. Points located near the corners of the mission should not be used as checkpoints.
Tagging checkpoints is optional.
- Click Confirm to open the processing menu.
- Verify your GCP Settings in the processing menu, then verify your processing settings and click Process.
In this section, you learned how to manually tag your images with GCPs to improve accuracy in your Site Scan projects.