Discrete, nonlinear curvature-dependent contour evolution

Abstract There has been much recent interest in curvature-dependent contour evolution processes, particularly when the resultant family of contours satisfies the heat (diffusion) equation. Computer simulations of these processes have used high-precision computation to closely approximate the solutions to the equation. This paper describes a class of low-precision contour evolution processes, based on a digital approximation to the curvature of the contour derived from its chain code, that can be applied to contours in low-resolution digital images. We have found that these methods perform quite similarly to the PDE-based methods at much lower computational cost. Our methods are also not limited to using linear functions of the contour’s curvature; we give several examples of digital contour evolution processes that depend nonlinearly on curvature, and discuss their possible uses.