  This report describes the design, implementation, evaluation and original
enhancements to the Live-Wire method for 2D and 3D image segmentation.
Live-Wire 2D employs a semi-automatic paradigm; the user is asked to select a
few boundary points of the object to segment, to steer the process in the right
direction, while the result is displayed in real time. In our implementation
segmentation is extended to three dimensions by performing this process on a
slice-by-slice basis. User's time and involvement is further reduced by
allowing him to specify object contours in planes orthogonal to the slices. If
these planes are chosen strategically, Live-Wire 3D can perform 2D segmentation
in the plane of each slice automatically. This report also proposes two
improvements to the original method, path heating and a new graph edge feature
function based on variance of path properties along the boundary. We show that
these improvements lead up to a 33% reduction in interaction with the user, and
improved delineation in presence of strong interfering edges.
