Recognition of local symmetries in gray value images by harmonic functions

Author

Bigün, Josef

Author_Institution

Dept. of Electr. Eng., Linkoping Univ., Sweden

fYear

1988

Firstpage

345

Abstract

A method for modeling symmetries of the neighborhoods in gray-value images is derived. It is based on the form of the iso-gray-value curves. For every neighborhood a complex number is obtained through a convolution of a complex-valued image with a complex-valued filter. The magnitude of the complex number is the degree of symmetry with respect to the a priori chosen harmonic function pair. The degree of symmetry has a clear definition which is based on the error in the Fourier domain. The argument of the complex number is the angle representing the relative dominance of one of the pair of harmonic functions compared to the other

Keywords

computer vision; computerised pattern recognition; computerised picture processing; filtering and prediction theory; harmonic analysis; Fourier domain error; complex-valued filter; complex-valued image; computer vision; convolution; gray value images; harmonic function pair; iso-gray-value curves; local symmetry recognition; neighbourhood symmetry modelling; pattern recognition; picture processing; Application software; Computer vision; Coordinate measuring machines; Fourier transforms; Image recognition; Least squares approximation; Least squares methods; Power harmonic filters;

fLanguage

English

Publisher

ieee

Conference_Titel

Pattern Recognition, 1988., 9th International Conference on

Conference_Location

Rome

Print_ISBN

0-8186-0878-1

Type

conf

DOI

10.1109/ICPR.1988.28238

Filename

28238