Implicit Snakes: Active Constrained Implicit Models

We are exploring new techniques for active contour models (popularlykno wn as "snakes"[1]) bycom bining active segmentation models with the constrained implicit surface model introduced bySa vchenko, et al.[4] and reintroduced under the name of variational implicit surfaces as a modeling and shape morphing tool byT urk and O'Brien[5]. In related work, we pursued more efficient numerical methods for these techniques. For a more complete description of our modeling methods, see Morse[2]. Here we show that an active surface model can be created byco mbining constrained implicit surfaces with a solver that minimizes an appropriate functional. In these examples, our energy minimization techniques are relativelysimple; new work in combing the active implicit modeling techniques with aggressive energyf unctionals is in progress. Byextr acting implicit models from discrete volume data, we are diverging from similar modeling methods described by Yngve and Turk[6].