Contour feature-based method for identification and segmentation of touching characters

摘要

Characters which touch one another in a document image are identified and separated in accordance with their contours. The objects in the image are divided into two classes comprising, respectively, those having closed inner contours and those which do not. An object in the first class having either a closed inner contour which is not centered in the object or two horizontally offset closed inner contours or more than two closed inner contours is identified as containing two touching characters and is split in accordance with the character stroke thickness observed in the document. An object in the second class whose contours intersect three spaced horizontal reference lines at more than a predetermined number of points is compared against intersection patterns characteristic of single characters. If a match is not found, the object is identified as containing touching characters.