We introduce a new matched filter method that yields correlation peaks that are invariant with changes in the illumination of any targets. A scene containing objects at unknown locations is first subjected to a logarithmic transformation that changes the multiplicative constant to an additive background, which is then discriminated against by means of a composite filter containing a cameo of the true target and a term with which to discriminate against other false targets. Experimental results are shown.
© 2000 Optical Society of America
(070.6110) Fourier optics and signal processing : Spatial filtering
(110.2970) Imaging systems : Image detection systems
(150.2950) Machine vision : Illumination
(200.4740) Optics in computing : Optical processing
Henri H. Arsenault and Daniel Lefebvre, "Homomorphic cameo filter for pattern recognition that is invariant with changes in illumination," Opt. Lett. 25, 1567-1569 (2000)