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ABSTRACT

A method for extracting a smooth polygonal contour from a digitized image is illustrated. The ordered sequence of contour points and the connection graph of the image are first obtained by a modified Ledley algorithm in one image scan. A minimal perimeter polygon subjected to specified constraints is then chosen as the approximating contour. The determination of the minimal polygon can be reduced to a nonlinear programming problem, solved by an algorithm which takes into account the weak bonds between variables. Some examples are presented, and the corresponding computing times are listed.

REFERENCES

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• 4: Azriel Rosenfeld , John L. Pfaltz, Sequential Operations in Digital Picture Processing, Journal of the ACM (JACM), v.13 n.4, p.471-494, Oct. 1966 [doi>10.1145/321356.321357]
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INDEX TERMS

Keywords:
connection tree, digitized image, minimal polygon, nonlinear programming, optimal approximation