A semi-automated line tracing technique for monitoring ice margins in Antarctic images

The current shape and rate of change of the margins of the Antarctic ice sheet are poorly known. Since polar regions are inhospitable, remotely sensed images provide an invaluable data source for studying the ice margin. These images can be examined by a human expert or processed automatically by a computer. This paper describes the design and implementation of a semi-automated technique to trace ice margins in Synthetic Aperture Radar images. The technique is based on a deformable contour model derived from the Kass et al. active contour model and Lobregt and Viergever's discrete dynamic contour. The contour is initialized by the user, to approximate the margin, and the deformation process causes the contour to accurately mould itself to the shape of the margin. The technique has been tested on a number of different images, with acceptable results in most cases. © 2006 Taylor & Francis.