Obliques and Merge for 3D model Construction

Introduction:

All of the imagery processed for this class up to this point has been captured from Nadir (pointing straight at the ground). Imagery captured at nadir is fantastic for the creation of orthomosaics and DSMs, but does not create aesthetically appealing 3D models. For 3D model creation, imagery captured at nadir and at oblique angles need to be fused into the same project.

Methods:

First, I ran the initial processing on the farm nadir flight, as well as the initial processing for the barn oblique flight. Next, I merged the two projects in Pix4D and ran the initial processing. After the initial processing, I noticed the flights had a 3m vertical offset between them, so I created two manual tie points, which re-aligned them into the same vertical plane.

Results:

The merged point cloud showed considerably more detail than the nadir generated orthomosaic.

Figure 1: 

Conclusion:

Oblique imagery provides increased detail to 3D models, however, the increased detail isn't necessarily worth the increased processing time.