The fastest way…..2 steps
Software tested : 3Dsurvey
Start with loading all reletad images into the application. Then select “Bundle Adjustment”. Select “Orientate” use “Orientate With Telemetry Data” if you rely on drone picture metadata where no GCP done on site. Proceed with “Reconstruction” and select reconstruction level to “high”, minimum overlapping “2” and select “Optimized Point Cloud”.
Under “Point cloud” menu select “Calculate New”.
Once completed select “Calculate profile” then select “Select Profile Definition Line” then drag a line (where cross-section is require) on the point cloud. Select ‘Profile” tab on the right of your screen. The results of surface profile selected is shown below.
This cross-section can be exported to autocad in .dwg format for further process. Note that the profile generated is based on unclasssified point cloud. To generate terrain profile, point cloud classification process shall be carried out. The contour generated from unclassified point cloud is shown below.