Shift- and scale-invariant recognition of contour objects with logarithmicradial harmonic filters

Citation
A. Moya et al., Shift- and scale-invariant recognition of contour objects with logarithmicradial harmonic filters, APPL OPTICS, 39(29), 2000, pp. 5347-5352
Citations number
27
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
APPLIED OPTICS
ISSN journal
00036935 → ACNP
Volume
39
Issue
29
Year of publication
2000
Pages
5347 - 5352
Database
ISI
SICI code
0003-6935(20001010)39:29<5347:SASROC>2.0.ZU;2-V
Abstract
The phase-only logarithmic radial harmonic (LRH) filter has been shown to b e suitable for scale-invariant block object recognition. However, an import ant set of objects is the collection of contour functions that results from a digital edge extraction of the original block objects. Therefore, since the energy of the contour objects decreases more slowly with the scale fact or than does the energy of the block objects, the phase-only LRH filter has difficulties in the recognition tasks when these contour objects are used. We propose a modified LRH filter that permits the realization of a shift- and scale-invariant optical recognition of contour;objects. The modified LR H filter is a complex filter that compensates the energy variation resultin g from the scaling of contour objects. Optical results validate the theory and show the utility of the newly proposed method. (C) 2000 Optical Society of America. OCIS code: 100.5010.