Active contour without edge

implementation of a well known level set method, easy to read code

Implementation of the level set method proposed in[1](ACWE) while add the regularity term[2] to avoid re-initialization.
The core function to implement ACWE is 'acwe.m',while 'demo_acwe.m' is for demonstration purpose.
Acknowledgement:
Li chunming for his clearly coded distribution:
http://www.mathworks.com/matlabcentral/fileexchange/12711-level-set-for-im
Reference:

[1]. T. Chan and L. Vese, “Active contours without edges,” IEEE Trans.
Image Process., vol. 10, no. 2, pp. 266–277, Feb. 2001
[2]. Minimizaion of region-scalable fitting energy for image segmentation.
IEEE Trans. Image Processing, vol. 17 (10), pp.1940-1949, 2008.by Li chunming etc.