A New External Force for Active Contour Model: Virtual Electric Field

Snake, known as an active contour model, is an energyminimizing deformable contour that converges the boundary of an object in image. For converging object’s boundary, snake is forced by internal force associated with the shape of contour and by external force invoked by the edges or the lines of the object. However the external force in traditional snake has some problems; limited capture range, sensitivity to initialization of contour, poor convergence to boundary concavities and etc. In this paper, we present new external force for solving problems above. The proposed external force is based on the virtual electric field that is made by the virtual electric charges on the boundary of the object, where the intensities or the edges of image are considered as the virtual electric charges. Also we show that the new external force by virtual electric field can be computed by convolution for fast calculation.