An example:
The dashed cyan contours are the boundaries of the capture ranges obtained by segmenting the external force field, and are used as the initial snakes.
Reference:
Chunming
Li, Jundong Liu, and Martin D. Fox, “Segmentation of Edge Preserving
Gradient Vector Flow: An Approach Toward Automatic Initialization and Splitting of
Snakes”, IEEE International
Conference on
Computer Vision and Pattern Recognition
(CVPR), San Diego, 2005.