1 August 1992 Morphological approach to machine-printed character recognition: a feasibility study
Author Affiliations +
Abstract
A connected skeleton is obtained from the image of a character on a rectangular grid with binary values, by use of discrete morphological processing with respect to a set of structuring elements. The skeletonizing procedure is based on sequential thinning, a well known morphological operation involving multiple use of the hit-miss transform. However, the sequence of thinning operations is carefully chosen to provide for robustness of resulting skeleton and its characteristic points (intersections and extremes) that are identified subsequently. Connectivity graphs of intersections and extremes of a character image are an affine invariant feature useful for character recognition. Ambiguities in character classification based on this feature are due to the fact that the graph adjacency (connectivity) matrix does not tell the difference between characteristic points connected by a stroke representing a straight line and a stroke representing a curve. An orthogonal fitting technique is proposed that discriminates between curved and straight strokes. Straight lines are then represented by graph edges, while the curves are replaced by a few additional mutually connected graph vertices. Experimental results show good discrimination properties of the extended connectivity graphs on 12 points Courier font characters.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Radovan V. Krtolica, Brian Warner, "Morphological approach to machine-printed character recognition: a feasibility study", Proc. SPIE 1661, Machine Vision Applications in Character Recognition and Industrial Inspection, (1 August 1992); doi: 10.1117/12.130279; https://doi.org/10.1117/12.130279
PROCEEDINGS
12 PAGES


SHARE
RELATED CONTENT

Character recognition by algebraic invariant matrix
Proceedings of SPIE (October 01 1992)
Spotting phrases in lines of imaged text
Proceedings of SPIE (March 30 1995)
Fast multi-class distance transforms for video surveillance
Proceedings of SPIE (February 26 2008)
Applications of matrix morphology
Proceedings of SPIE (November 01 1990)

Back to Top