Acquisition of the 3D boundary of the Triglav glacier from archived non-metric panoramic images

作者：Triglav Cekada Mihaela^*; Radovan Dalibor; Gabrovec Matej; Kosmatin Fras Mojca

来源：Photogrammetric Record, 2011, 26(133): 111-129.

DOI：10.1111/j.1477-9730.2011.00622.x

• 3D data acquisition from a single image
• clinometry
• convergent panoramic images
• Horizont camera
• interactive orientation
• shape-from-shading
• Triglav glacier

A panoramic, non-metric, Horizont camera has been used for regular, monthly, close-range photography of the rapidly retreating Triglav glacier in Slovenia since 1976. The unfavourable geometry of the convergent images taken from the two camera stations has made any direct stereoscopic observation and recording impossible. The aim of this research was to define the most useful method for acquiring 3D data from these panoramic, convergent images. The Horizont camera was calibrated and three methods were then tested: the generation of pseudo-orthophotographs, the application of 2D clinometry and the interactive orientation of a detailed digital elevation model (DEM) on the images. The third turned out to be the only method suitable for determining the boundary of the Triglav glacier.
The interactive orientation of a detailed DEM on the Horizont images is described in detail. The 3D glacier boundary can be acquired from individual Horizont images (camera stations A and B) enabling the computation of the glacier's area and theoretical volume. By repeating the glacier boundary acquisition for different orientation parameters, the standard deviations of the glacier area and theoretical volume were computed. Because of the more precise average area and volume measurements achieved with the camera station B images, only these were chosen for the glacier disappearance study. Every third year between 1976 and 2005 the Horizont images were used to compute the changes in the area and volume of the glacier. The glacier area was found to have reduced to 8% of its earlier size, from 15 ha in 1976 to 1 center dot 2 ha in 2000. However, owing to harsher than average winters since then the decline in the glacier area was found to have slowed in the past decade (2000 to 2009). The glacier's theoretical volume decreased roughly exponentially from 1976 to 2005.

• 出版日期2011-3