4. The method of claim 2, wherein said step of identifying rectangular boundaries comprises the steps of: (a) locating associated pixels at horizontal and vertical extremes of each group of black pixels associated with a first black pixel; and (b) determining a rectangular boundary about each group, the rectangular boundary representing the horizontal and vertical extremes.
4. The method of claim 2, wherein said step of identifying rectangular boundaries comprises the steps of: (a) locating associated pixels at horizontal and vertical extremes of each group of black pixels associated with a first black pixel; and (b) determining a rectangular boundary about each group, the rectangular boundary representing the horizontal and vertical extremes. 5. The method of claim 4, wherein the rasterized data defining the image is a bitmap rasterized with respect to a pair of orthogonal image axes, and said boundary determining step determines a rectangular box, the major axes of which are parallel to the image axes.