Structure from Motion

Structure from Motion (SfM) refers to algorithms by which you can calculate - based on many overlapping images - both the relative camera geometry (motion) and the 3D structure captured by the image (structure). Thus, in theory, you can take a whole bunch of pictures of say of a hillside or a glacier and create a digital surface model using SfM - intriguing!

Examples: Westoby et al. (2012)  or Ryan et al. (2014).
Nice review of SfM: Smith et al. (2016)

• Bundler (Univ. of Washington)
• VisualSFM (Univ. of Washington)
• Agisoft (commercial product)
• SFMToolkit

Fairbanks Fodar is a semi-commercial company out of Fairbanks (AK) claiming that they can deliver LiDAR quality data at 10 percent of the cost.