In [4], the authors have proposed a generalization of the classical Fast Marching Method of Sethian for the eikonal equation in the case where the normal velocity depends on space and time and can change sign. The goal of this paper is to propose a modified version of the Generalized Fast Marching Method proposed in [4] for which we state a general comparison principle. We also prove the conver...

A computational study of the Fast Marching and the Fast Sweeping methods for the Eikonal equation is given. It is shown that even though Fast Sweeping requires asymptotically less operations than Fast Marching, the latter method is faster than the former for the problems under consideration and for realistic grid sizes. Fully second order generalizations of methods of this type for problems wit...

We present two numerical methods for the fully nonlinear elliptic MongeAmpère equation. The first is a pseudo transient continuation method and the second is a pure pseudo time marching method. The methods are proved to converge for smooth solutions. We give numerical evidence that they are also able to capture the viscosity solution of the Monge-Ampère equation. Even in the case of the degener...

This paper describes the Subgradient Marching algorithm to compute the derivative of the geodesic distance with respect to the metric. The geodesic distance being a concave function of the metric, this algorithm computes an element of the subgradient in O(N log(N)) operations on a discrete grid ofN points. It performs a front propagation that computes the subgradient of a discrete geodesic dist...

This paper presents a novel method for the generation of myocardial wall surface meshes from segmented 3D MR images, which typically have strongly anisotropic voxels. The method maps a premeshed sphere to the surface of the segmented object. The mapping is defined by the gradient field of the solution of the Laplace equation between the sphere and the surface of the object. The same algorithm i...

Accurate and efficient traveltime calculation is an important topic in seismic imaging. We present a fast-marching eikonal solver in the tetragonal coordinates (3-D) and trigonal coordinates (2-D), tetragonal (trigonal) fast-marching eikonal solver (TFMES), which can significantly reduce the first-order approximation error without greatly increasing the computational complexity. In the trigonal...