Snake Algorithm

Snakes, or active contours, are curves defined within an image domain that can move under the influence of internal forces coming from within the curve itself and external forces computed from the image data. The goal is to find a contour that best approximates the perimeter of an object. It is helpful to visualize it as a rubber band of arbitrary shape that is capable of deforming during time, trying to get as close as possible to the target contour.
Please see the attached document "overview.pdf" to understand the underlying equations and algorithm used to develop this toolbox.
Please visit the following link to see an example:
https://www.youtube.com/watch?v=SdqBNFx-uNc