Browse Prior Art Database

Fast Straight Line Matcher Compatible with Elastic Matching in on Line Handwriting Recognition

IP.com Disclosure Number: IPCOM000106871D
Original Publication Date: 1993-Dec-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 2 page(s) / 65K

Publishing Venue

IBM

Related People

Chefalas, TE: AUTHOR [+2]

Abstract

Disclosed is a method of rapidly calculating a matching distance between two straight lines that estimates an idealized elastic match. The straight-line distance scores are comparable to elastic matching scores and can be used for comparing straight and curved strokes. Computation speed is critical for on-line handwriting recognition systems because such systems usually run on small stand-alone computers.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Fast Straight Line Matcher Compatible with Elastic Matching in on Line Handwriting Recognition

      Disclosed is a method of rapidly calculating a matching
distance between two straight lines that estimates an idealized
elastic match.  The straight-line distance scores are comparable to
elastic matching scores and can be used for comparing straight and
curved strokes.  Computation speed is critical for on-line
handwriting recognition systems because such systems usually run on
small stand-alone computers.

      This online, handwriting recognition system uses elastic curve
matching to match an unknown character against prototype (template)
characters [*].  Matching is done on a stroke-by-stroke basis, where
a stroke is the writing from pen down to pen up.  Elastic matching
allow in the matching process to optimize the fit, thus handling
normal distortions of curved strokes.  However, many strokes of
handwritten characters, especially uppercase printed characters, are
straight and therefore elasticity in the matching process is not
necessary.

      Details of the method follow.  The preprocessing step of
filtering yields equally-spaced points along the trajectory.  The
matching process aligns the centers of gravity of the two lines being
matched.  Since the elastic matcher matches all N points of the
unknown to points of the prototype, we match N equally-spaced points
of the unknown straight line to N equally-spaced points of the
prototype straight line.  The Figure illustrate...