Joint wavelet transform correlation with separated target and reference planes

Boon Yi Soon,Russell Hardie,Mohammad Alam,Mohammad Karim

doi:10.1364/oe.2.000177

Abstract

In recent years, we realize the usefulness of feature extraction for optical correlator and hereby, we investigate the capability of Laplace operator in feature extraction of multiple targets. The first-order terms and the false alarm terms in the correlation output would be removed using electronic power spectrum subtraction technique. Most importantly, the entire magneto-optic SLM is completely utilized for displaying only targets in the input scene. A new cost efficient hardware implementation is proposed and aforementioned result of the proposed system is evaluated through computer simulation.

Highlights

The optical correlator evolves through two main structures; the joint transform correlator (JTC) by Weaver and Goodman and the VanderLugt’s correlator by VanderLugt [1,2]
In recent years, we realize the usefulness of feature extraction for optical correlator and hereby, we investigate the capability of Laplace operator in feature extraction of multiple targets
The features extracted for the four cartoon images give comparable result to that of the Sobel and the Robert operators’

Summary

Introduction

The optical correlator evolves through two main structures; the joint transform correlator (JTC) by Weaver and Goodman and the VanderLugt’s correlator by VanderLugt [1,2]. The joint transform correlator has gone through many improvements [3] and has proved its usefulness in pattern recognition, feature extraction and target detection. Since the edge information is embedded in the high frequency content in the images, preprocessed images with wavelets are equivalent to high pass or band pass filtering the target object This would tremendously improve the proficiency of the correlation output for feature extraction [15]. In the correlation output plane, we would remove both the first-order and the false alarm terms using the power spectrum subtraction technique. This technique is more superior to the chirp-encoded joint transform correlator [18], which requires more equipment and precise optic alignment. We could rotate a half cycle along both x-axis and y-axis, and superimpose the pair of correlators to obtain a single stronger correlation peak

Theory

Computer simulation results

Conclusion