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Biometric verification with correlation filters
Applied Optics, 2004Using biometrics for subject verification can significantly improve security over that of approaches based on passwords and personal identification numbers, both of which people tend to lose or forget. In biometric verification the system tries to match an input biometric (such as a fingerprint, face image, or iris image) to a stored biometric template.
B V K, Vijaya Kumar +5 more
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Optimal real correlation filters
Applied Optics, 1991Expressions are derived for real filters that have a maximum correlation signal to noise ratio. Both continuous and discrete cases are treated and shown to have similar forms. The signal can be complex, and the case of a real signal is considered and related to previous results.
R D, Juday, B V, Kumar, P K, Rajan
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Performance measures for correlation filters
Applied Optics, 1990Several performance criteria are described to enable a fair comparison among the various correlation filter designs: signal-to-noise ratio, peak sharpness, peak location, light efficiency, discriminability, and distortion invariance. The trade-offs resulting between some of these criteria are illustrated with the help of a new family of filters called ...
B V, Kumar, L, Hassebrook
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Acoustooptic matched filter correlator
Applied Optics, 1982The signal model used and the output SNR(0) measure chosen are shown to affect the performance of an acoustooptic time-integrating correlator. Nonuniform acoustic fields are also shown to affect the results, but these error sources can be overcome with a new hybrid time- and space-integrating acoustooptic matched filter correlator that we describe and ...
D, Casasent, G, Silbershatz, B V, Kumar
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Wavelet filtering of correlated speckle
SPIE Proceedings, 2003In practice, SAR images are very often disturbed by a correlated speckle noise. Correlation influence on wavelet coefficients is a difficult problem degrading detection and filtering performances dramatically. We establish a simple analytic relation between high order wavelet coefficient moments/cumulants and speckle second order statistics.
Samuel Foucher +2 more
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Zero-aliasing correlation filters
2013 8th International Symposium on Image and Signal Processing and Analysis (ISPA), 2013Traditional correlation filters are designed and implemented via the frequency domain, where the correlation of two signals may be computed efficiently. However, when the discrete Fourier transform (DFT) of length N is used, multiplication in the frequency domain results in an N-point circular correlation, rather than a linear correlation.
Joseph A. Fernandez +1 more
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Correlation Filters for Object Alignment
2013 IEEE Conference on Computer Vision and Pattern Recognition, 2013Alignment of 3D objects from 2D images is one of the most important and well studied problems in computer vision. A typical object alignment system consists of a landmark appearance model which is used to obtain an initial shape and a shape model which refines this initial shape by correcting the initialization errors.
Vishnu Naresh Boddeti +2 more
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Quadratic correlation filters for optical correlators
SPIE Proceedings, 2003Linear correlation filters have been implemented in optical correlators and successfully used for a variety of applications. The output of an optical correlator is usually sensed using a square law device (such as a CCD array) which forces the output to be the squared magnitude of the desired correlation.
Abhijit Mahalanobis +2 more
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Object Tracking by Branched Correlation Filters and Particle Filter
2017 4th IAPR Asian Conference on Pattern Recognition (ACPR), 2017Correlation filter based tracking which is one of the tracking-by-detection methods, has demonstrated competitive performance in recent years. However, once the detected position is incorrect, the parameter of correlation filter is updated based on the appearance of the incorrect position.
Hitoshi Nishimura +3 more
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Geophysics, 1954
Abstract Correlation analysis techniques may be applied to seismic data already subjected to standard recording and analysis procedure in an effort to extract additional information, or to raw data as an alternative filtering method. These techniques involve determination of certain parameters which provide a quantitative measure of ...
Hal J. Jones, John A. Morrison
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Abstract Correlation analysis techniques may be applied to seismic data already subjected to standard recording and analysis procedure in an effort to extract additional information, or to raw data as an alternative filtering method. These techniques involve determination of certain parameters which provide a quantitative measure of ...
Hal J. Jones, John A. Morrison
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