British Society for Geomorphology Geomorphological Techniques, Chap. 2, Sec. 2.2 (2015)
Structure from Motion (SfM) Photogrammetry
Natan Micheletti
1
, Jim H Chandler
2
, Stuart N Lane
1
1
Institute of Earth Surface Dynamics, University of Lausanne (natan.micheletti@unil.ch)
2
School of Civil and Building Engineering, Loughborough University
ABSTRACT: Topographic data measurement is a fundamental aspect of many geomorphic
research applications, particularly those including landform monitoring and investigation of
changes in topography. However, most surveying techniques require relatively expensive
technologies or specialized user supervision. Structure from Motion (SfM) photogrammetric
technology reduces both these constraints by allowing the use of consumer grade digital cameras
and highly automated data processing, which can be free to use. SfM photogrammetry therefore
offers the possibility of fast, automated and low-cost acquisition of 3-D data, which has inevitably
created great interest amongst the geomorphological community. In this contribution, the basic
concepts of SfM photogrammetry are presented, whilst recognising its heritage. A few examples
are employed to illustrate the potential of SfM applications for geomorphological research. In
particular, SfM photogrammetry offers to geomorphologists a tool for high-resolution
characterisation of 3-D forms at a range of scales and for change detection purposes. The high
level of automation of SfM data processing creates both opportunities and threats, particularly
because user control tends to focus upon visualisation of the final product rather than upon
inherent data quality. Accordingly, this contribution seeks to guide potential new users in
successfully applying SfM for a range of geomorphic studies.
KEYWORDS: Structure from Motion, close-range photogrammetry, smartphone technology, surveying
systems, surface morphology
Introduction
Geomorphological approaches for the
acquisition of topographic data are
experiencing a remarkable technological leap
nowadays, with both a substantial increase in
the possible frequency of three-dimensional
terrain surveying and the ease in which
associated methods can be applied.
Traditionally, topographic research focused
upon constructing digital elevation models
(DEMs) using photogrammetric (e.g. Lane et
al., 1994; Barker et al., 1997; Chandler, 1999;
Lane, 2000; Westaway et al., 2000; Bennett
et al., 2012) and differential global positioning
system (dGPS) (e.g. Fix and Burt, 1995;
Brasington et al., 2000; Young, 2012) data.
More recently, both airborne and terrestrial
laser scanner have been widely employed to
collect very high-quality and high resolution
data (Heritage and Hetherington, 2007; Alho
et al., 2009; Hodge et al., 2009a, 2009b;
Schaefer and Inkpen, 2010). However, most
of these techniques still require expensive
equipment and specialized user expertise to
process data and improve its quality. In
contrast, the development of Structure from
Motion (SfM) methods provides the
opportunity for very low-cost three-
dimensional data acquisition with strongly
reduced user supervision and required
expertise. The ability to extract high
resolution and accurate spatial data using
cheap consumer grade digital cameras
appears truly remarkable and SfM
photogrammetry could answer a range of
new research questions.
As in traditional photogrammetry, SfM
photogrammetry employs overlapping images
acquired from multiple viewpoints. However,
SfM photogrammetry differs from traditional
photogrammetric approaches by determining
internal camera geometry and camera
ISSN 2047-0371
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