1. A method for error correction for segmented three dimensional image data, comprising: receiving segmented three dimensional image data, the segmented three dimensional image data comprising a plurality of parallel slices; correcting at least one contour of the segmented three dimensional image data on at least one slice according to a command from a user to form a corrected contour, wherein the correcting the at least one contour of the segmented three dimensional image data according to the command from the user comprises: receiving an input contour correction from the user; and correcting the at least one contour from the input contour correction according to a two dimensional contour algorithm; automatically interpolating a correction represented by the corrected contour only to the plurality of parallel slices, wherein the automatically interpolating comprises interpolating between the corrected contour and an adjacent user defined contour by applying a geometric interpolation method to interpolate the shape of one contour line to the shape of the other contour line across at least one intervening slice; shrinking each geometrically interpolated contour line; and evolving each contour line separately to form a final contour line.