Title :
Algorithm for detecting images in defocused scenes using optical correlation
Author :
Carnicer, Arturo ; Vallmitjana, Santiago ; Martin-Badosa, Estela ; Juvells, Ignacio
Author_Institution :
Dept. of de Fisica Aplicada i Electron., Barcelona Univ., Spain
Abstract :
An original method used to detect images in defocused scenes by means of a binary joint transform correlation is presented. The optical transfer function of the imaging lens, which presents positive and negative values, introduces sign errors in the joint power spectrum. The goal of this study is to detect the sign of the optical transfer function starting from the defocused image by means of a digital algorithm, to compensate the sign errors in the binary joint power spectrum and to obtain invariant correlations with respect to defocusing. Theoretical analysis and digital experiments to test the procedure are provided
Keywords :
error analysis; image recognition; optical correlation; optical focusing; optical transfer function; spectral analysis; transforms; binary joint power spectrum; binary joint transform correlation; defocused image; defocused scenes; defocusing; digital algorithm; digital experiments; image detection algorithm; imaging lens; invariant correlations; optical correlation; optical transfer function; pattern recognition; sign errors compensation; Correlators; Degradation; Equations; Laboratories; Layout; Lenses; Optical imaging; Pattern recognition; Testing; Transfer functions;
Conference_Titel :
Image Processing, 1996. Proceedings., International Conference on
Conference_Location :
Lausanne
Print_ISBN :
0-7803-3259-8
DOI :
10.1109/ICIP.1996.559603
