1. A method for processing digital mesh images representations of three-dimensional subjects, said method comprising: slicing said mesh representation with a frontal imaginary plane that divides the mesh representation into anterior and posterior sections; slicing said mesh representation with a sagittal imaginary plane extending vertically through said mesh representation dividing said mesh representation into left and right sections, said frontal imaginary plane intersecting said sagittal imaginary plane; and using a spline function to fit smoothed splines to selected ones of said anterior and posterior sections and said left and right sections.