thn_lc

[ XITE Reference Manual | XITE home ]

Name

thn_lc - Lee and Chen's thinning method.

Syntax

thn_lc <inimage> <outimage>

Description

Thin a binary image with Lee and Chen's method. Black (0) is foreground, and white (255) is background.

This method is simply an extension of Zhang and Suen's method. First, Zhang and Suen's methhod is used. The skeleton thus obtained is not truly 8-connected, since some non-junction pixels have more than two neighbors, making the skeleton useless for algorithms that require this constraint. Therefore, some pixels have to be removed. The skeleton is inspected, and each pixel is tested using a lookup table. The result is a true 8-connected skeleton where only junction pixels have more than two 8-neighbors.

Restrictions

inimage must have bands with pixel type unsigned byte. The input is assumed to be binary valued with foreground = 0, background = 255.

See also

thn_lc(3), thn_har(1), thn_zs(1)

Reference

H.-J. Lee and B. Chen,
"Recognition of handwritten chinese characters via short line segments," Pattern Recognition, vol. 25, no. 5, pp. 543-552, 1992.

Files

xite/src/thin/thn_lc.c

Author

Řivind Due Trier, late one night at Michigan State University.

Id

$Id: thn_lc.c,v 1.13 1997/01/16 16:11:49 svein Exp $