Snakes, Active Contours, and Segmentation

The basic idea in active contour models (or snakes) is to evolve a curve, subject to constraints from a given image u 0, in order to detect objects in that image. Ideally, we begin with a curve around the object to be detected, and the curve then moves normal to itself and stops at the boundary of the object. Since its invention by Kass et al. [94] this technique has been used both often and successfully. The classical snakes model in [94] involves an edge detector, which depends on the gradient of the image u 0, to stop the evolving curve at the boundary of the object.