Abstract: In one embodiment of the present invention, a method of generating a zero-offset trace, at a zero-offset location on a processing plane, for a time sampled recording is provided. The time sampled recording has a source and receiver, and a source coordinate and a receiver coordinate associated therewith. The time sampled recording also has an amplitude and a sampled time associated therewith. The method comprises reading the source and receiver coordinates and determining an ellipsoid dependant upon the source-receiver offset, the sampled time, and the velocity of the medium. The ellipsoid has the source as one focus and the receiver as the other focus. The method further comprises determining a set of normal points on the ellipsoid and determining the distance between each of the normal points and the zero-offset trace location and dividing twice the distance by the velocity of the medium, wherein the zero-offset travel time for each normal point is determined.