Method of nonlinear equalization of degraded document images

Details Method of nonlinear equalization of degraded document images Method of nonlinear equalization of degraded document images

1997-03-12

1998-04-28

Rogers, Scott A.

Image analysis

Pattern recognition

Limited to specially coded, human-readable characters

382209, 382261, G06K 900, G06K 962, G06K 940, G06T 510

Patent

active

057455970

ABSTRACT:
A method identifies and models the distortion in a document using a two-dimensional nonlinear filter. The two-dimensional nonlinear filter is then used to improve the performance of optical character recognition systems in recognizing characters in documents that have been degraded, as for example by repeated photocopy reproductions or by fax transmission.

REFERENCES:
patent: 5285505 (1994-02-01), Kim et al.
patent: 5490223 (1996-02-01), Nishimura et al.
S. Mori et al., "Historical Review of OCR Research and Development," Proceeding of the IEEE, vol. 88, No. 7, 1029-1057, (Jul. 1992).
V.K. Govindan et al., "Character Recognition -A Review," Pattern Recognition, vol. 23, No. 7, 67-683, (1990).
C.F.N. Cowan et al., "Non-Linear System Modelling: Concept and Application," Proc. 1984 ICASSP, 4561-4564, (1984).
T. Endoh et al., "Progressive Reduction Standard for Bi-level Images," JBIG-ISO JTCI/SC2/WG8 CCITT SG VIII,(Jul. 1989).
L.O'Gorman, "Image and Document Processing Techniques for the RightPages Electronic Library System," Proc. 1992 Int'l Conf. on Pattern Recognition, vol. II, 260-263, (1992).

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