From UAV to Orthomosaic: Building a Toolchain
Our mission was to create an orthomosaic starting only with the image sequence from a UAV flight. Typically this data is not highly calibrated; the camera characteristics may not be known and motion sensor data may not be present. Structure from Motion (SfM) offers a photogrammetric method for creating 3D models out of overlapping aerial imagery. This model in turn can be draped with the images to produce our orthomosaic.
I'll present the results of our efforts to build an Open Source toolchain to accomplish this workflow, with a focus on how SfM works and the successes and pitfalls we encountered.