The Coastal Ecosystem Mapping and Media Viability Project

Figure 4. This figure depicts how the location of GCPs as computed from the drone images and from the GPS measurements differ. The GPS measurements are more precise, and therefore these are used to georeference the drone images in virtual space. These points can also be created by directly importing the GPS information into Pix4D. After all the points with the GPS location of the GCPs are created in the GCP/Manual Tie Point Manager , the Basic Editor tool in Pix4D is used to manually tie the GPS points to the center of the tarps on the images taken from the drone (figure 9, figure 10).

Figure 16. The Basic Editor tool used to tag each GPS point back to the GCPs on images taken by the drone. At least 3 GCPs need to be tagged to georeference an image. The GCPs should be placed in the corners and centre of the study area for the best georeferencing results. Figure 5. The Basic Editor tool used to tag each GPS point back to the GCPs on images taken by the drone. At least 3 GCPs need to be tagged to georeference an image. The GCPs should be placed in the corners and center of the study area for the best georeferencing results. After each GPS point is correctly linked to the drone’s images, the Pix4D software accurately relocates and scales the 3D image (figure 11) (Process => Reoptimize).

The Coastal Ecosystem Mapping and Media Viability Project

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