Implementation and improvement based on variational level set method

As a deformable model, the level set method is a numerical technique for tracking interfaces and shapes. The advantage of the level set method is that one can perform numerical computations involving curves and surfaces on a fixed Cartesian grid without having to parameterize these objects. Also, the level set method makes it very easy to follow shapes that change topologys. During the evolution of the level set funciton the choice of time step is a critical mask. It can´t be too large or small. In this paper a variable time step is used in the evolution to satisfy the different regions.