Adaptive Vector Flow for Active Contour Model

A novel external force for active contours, called as adaptive vector flow (AVF), is proposed in this paper. Based on analyzing the diffusion mechanism of gradient vector flow (GVF), it is found that GVF is difficult to preserve weak edges and enter long and thin concavities. In AVF, we replace the isotropic smoothness term of GVF by an adaptive anisotropic one and adjust the diffusion speed in tangent and normal directions by the local features of the images. Experimental results on synthetic and real images show that, compared with the GVF snake, the AVF snake has better performance and properties.