level set segmentation using coupled active surfaces

An Insight Toolkit (ITK) processing framework for simultaneous segmentation of multiple objects using active contours without edges is presented in this paper. These techniques are also popularly referred to as multiphase methods. Earlier, we had an implemented the Chan and Vese [1] algorithm that uses level- sets to accomplish region segmentation in images with poor or no gradient information. The current work extends that submission to use multiple level sets that evolve concurrently. The basic idea is to partion the image into several sets of piecewise constant intensity regions. This work is in contrast to the level-set methods currently available in ITK which necessarily require gradient information and also necessarily segment a single object-of-interest. Similar to those methods, the methods presented in this paper are also made efficient using a sparse implementation strategy that solves the contour evolution PDE at the level-set boundary. This work does not introduce any new filter but extends the earlier submitted to filters to process multiple objects. We include 2D/3D example code, parameter settings and show the results generated on a 2D cardiac image.