What can we learn from the shape of a correlation peak for position estimation?

Matched filtering is a robust technique to identify and locate objects in the presence of noise. Traditionally, the amplitude of the correlation peak is used for detection of a match. However, when distinguishing objects that are not significantly different or detecting objects under high noise imaging conditions, the normalized peak amplitude alone may not provide sufficient discrimination. In this paper, we demonstrate that measurements derived from the shape of the correlation peak offer not only higher levels of discrimination but also accurate position estimation. To our knowledge, this is the first time such features have been used in a real-time system, like the National Ignition Facility, where such techniques enable real-time, accurate position estimation and alignment under challenging imaging conditions. It is envisioned that systems utilizing matched filtering will greatly benefit from incorporating additional shape based information.

[1]  M. Karim,et al.  Discretized amplitudemodulated phase-only filter , 1996 .

[2]  Thad Salmon,et al.  Detection and tracking of the backreflection of potassium dihydrogen phosphate images in the presence or absence of a phase mask. , 2006, Applied optics.

[3]  Philippe Réfrégier,et al.  Optimal and suboptimal detection of a target with random grey levels imbedded in non-overlapping noise , 1996 .

[4]  A. B. Vander Lugt,et al.  Signal detection by complex spatial filtering , 1964, IEEE Trans. Inf. Theory.

[5]  S. Sutton,et al.  National Ignition Facility laser performance status. , 2007, Applied optics.

[6]  Abdul A. S. Awwal.  Automatic identification of the templates in matched filtering , 2004, SPIE Optics + Photonics.

[7]  M. Karim,et al.  Optimization of amplitude-modulated inverse filter , 1996 .

[8]  Bahram Javidi,et al.  Minimum mean-square-error filter for pattern recognition with spatially disjoint signal and scene noise , 1993 .

[9]  Abdul A. S. Awwal,et al.  Accurate position sensing of defocused beams using simulated beam templates , 2004, SPIE Optics + Photonics.

[10]  B. V. K. Vijaya Kumar,et al.  Correlation filters minimizing peak location errors , 1992 .

[11]  B. Kumar,et al.  Performance measures for correlation filters. , 1990, Applied optics.

[12]  Tarek M. Taha,et al.  Fast implementation of matched-filter-based automatic alignment image processing , 2008 .

[13]  S Vallmitjana,et al.  Application of fuzzy-rule-based postprocessing to correlation methods in pattern recognition. , 1996, Applied optics.

[14]  Abdul A. S. Awwal,et al.  Optimization and improvement of FOA corner cube algorithm , 2004, SPIE Optics + Photonics.

[15]  P C Miller,et al.  Demonstration of improved automatic target-recognition performance by moment analysis of correlation peaks. , 1999, Applied optics.

[16]  J L Horner,et al.  Pattern recognition with binary phase-only filters. , 1985, Applied optics.

[17]  Abhijit Mahalanobis.  Guest Editorial: Special Section on Correlation Pattern Recognition , 1997 .

[18]  Shoude Chang,et al.  Centroid detection based on optical correlation , 2002 .

[19]  Tarek M Taha,et al.  Hardware accelerated optical alignment of lasers using beam-specific matched filters. , 2009, Applied optics.

[20]  D. Casasent,et al.  Performance evaluation of minimum average correlation energy filters. , 1991, Applied optics.

[21]  Karl S Gudmundsson,et al.  Sub-imaging technique to improve phase only filter search capability. , 2003, Applied optics.

[22]  Abdul A. S. Awwal.  Multi-object feature detection and error correction for NIF automatic optical alignment , 2006, SPIE Optics + Photonics.

[23]  R S Caprari.  Method of target detection in images by moment analysis of correlation peaks. , 1999, Applied optics.

[24]  Ryan A. Kerekes,et al.  Selecting a composite correlation filter design: a survey and comparative study , 2008 .

[25]  Abhijit Mahalanobis,et al.  Optimality of the maximum average correlation height filter for detection of targets in noise , 1997 .

[26]  M A Karim,et al.  Multiprocessor design using polarization-encoded optical shadow-casting. , 1990, Applied optics.

[27]  Edward I. Moses.  Overview of the National Ignition Facility , 2007 .

[28]  Steven B. Sutton,et al.  Alignment and wavefront control systems of the National Ignition Facility , 2004 .