 |
| Titel |
Structure-from-Motion photogrammetry: a novel, low-cost tool for geomorphological applications |
| VerfasserIn |
M. Westoby, J. Brasington, N. F. Glasser, M. J. Hambrey, J. M. Reynolds |
| Konferenz |
EGU General Assembly 2012
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250059077
|
|
|
|
|
|
| Zusammenfassung |
| Presently, high-resolution surveying methods for geomorphological applications are accompanied by high start-up and data acquisition costs, as well as difficult portability. Consequently, the relative remoteness and inaccessibility of many field sites may render these approaches impractical. This paper outlines a revolutionary novel, low-cost, user-friendly photogrammetric technique for obtaining high-resolution datasets at a range of scales. Termed ‘Structure-from-Motion’ (SfM), the technique operates under the same basic assumption of stereoscopic photogrammetry, namely that 3-D structure can be resolved from two or more overlapping, offset images. Traditional softcopy photogrammetric methods require the 3-D location and pose of the camera(s), or the 3-D location of a series of control points to be known to facilitate scene triangulation and reconstruction. In contrast, the SfM approach requires neither of the above to be known prior to scene reconstruction. Instead, camera pose and scene geometry are reconstructed simultaneously through identification of matching features, or keypoints, in multiple images, and the subsequent application of an iterative, least-squares solution. However, SfM output is fixed into a relative, not absolute, co-ordinate system, and so some degree of ground control is required if the data are to be used quantitatively.
We provide a brief introduction to the principles of the SfM approach and outline the workflow employed, from photoset acquisition, through to the production of high-resolution (
|
|
|
|
|
|
|