OPTICAL FLOW FOR GLACIER MOTION ESTIMATION
Other literature type
Quantitative measurements of glacier flow over time are an important ingredient for glaciological research, for example to determine
the mass balances and the evolution of glaciers. Measuring glacier flow in multi-temporal images involves the estimation of a dense
set of corresponding points, which in turn define the flow vectors. Furthermore glaciers exhibit rather difficult radiometry, since
their surface usually contains homogeneous areas as well as weak texture and contrast. To date glacier flow is usually observed by
manually measuring a sparse set of correspondences, which is labor-intensive and often yields rather irregular point distributions,
with the associated problems of interpolating over large areas. In the present work we propose to densely compute motion vectors at
every pixel, by using recent robust methods for optic flow computation. Determining the optic flow, i.e. the dense deformation field
between two images of a dynamic scene, has been a classic, long-standing research problem in computer vision and image processing.
Sophisticated methods exist to optimally balance data fidelity with smoothness of the motion field. Depending on the strength of the
local image gradients these methods yield a smooth trade-off between matching and interpolation, thereby avoiding the somewhat
arbitrary decision which discrete anchor points to measure, while at the same time mitigating the problem of gross matching errors. We
evaluate our method by comparing with manually measured point wise ground truth.