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Audio- and Video-Based Biometric Person Authentication : Third International Conference, AVBPA 2001 Halmstad, Sweden, June 6–8, 2001 Proceedings
- 2001
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Proceedings (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- This book constitutes the refereed proceedings of the Third International Conference on Audio- and Video-Based Biometric Person Authentication, AVBPA 2001, held in Halmstad, Sweden in June 2001.The 51 revised papers presented together with three invited papers were carefully reviewed and selected for inclusion in the book. The papers are organized in topical sections on face as biometrics; face image processing; speech as biometrics and speech processing; fingerprints as biometrics; gait as biometrics; and hand, signature, and iris as biometrics.
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| 2. |
- Bigun, Josef, et al.
(författare)
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Assuring liveness in biometric identity authentication by real-time face tracking
- 2004
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Ingår i: CIHSPS 2004. - Piscataway, N.J. : IEEE Press. - 0780383818 - 9780780383814 ; , s. 104-111
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Konferensbidrag (refereegranskat)abstract
- A system that combines real-time face tracking as well as the localization of facial landmarks in order to improve the authenticity of fingerprint recognition is introduced. The intended purpose of this application is to assist in securing public areas and individuals, in addition to enforce that the collected sensor data in a multi modal person authentication system originate front present persons, i.e. the system is not under a so called play back attack. Facial features are extracted with the help of Gabor filters and classified by SVM experts. For real-time performance, selected points from a retinotopic grid are used to form regional face models. Additionally only a subset of the Gabor decomposition is used for different face regions. The second modality presented is texture-based fingerprint recognition, exploiting linear symmetry. Experimental results on the proposed system are presented.
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| 3. |
- Bigun, Josef, et al.
(författare)
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Evidence on skill differences of women and men concerning face recognition
- 2001
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Ingår i: Audio- and video-based biometric person authentication. - Berlin : Springer. - 3540422161 - 9783540453444 ; , s. 44-51
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We present a cognitive study regarding face recognition skills of women and men. The results reveal that there are in the average sizable skill differences between women and men in human face recognition. The women had higher correct answer frequencies then men in all face recognition questions they answered. In difficult questions, those which had fewer correct answers than other questions, the performance of the best skilled women were remarkably higher than the best skilled men. The lack of caricature type information (high spatial frequencies) hampers the recognition task significantly more than the lack of silhouette and shading (low spatial frequencies) information, according to our findings. Furthermore, the results confirmed the previous findings that hair style and facial expressions degrades the face recognition performance of humans significantly. The reported results concern 1838 individuals and the study was effectuated by means of Internet.
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| 4. |
- Bigun, Josef, 1961-, et al.
(författare)
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Multimodal biometric authentication using quality signals in mobile communications
- 2003
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Ingår i: Proceedings - 12th International Conference on Image Analysis and Processing, ICIAP 2003. - Los Alamitos, USA : IEEE Computer Society. - 0769519482 ; , s. 2-11
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The elements of multimodal authentication along with system models are presented. These include the machine experts as well as machine supervisors. In particular fingerprint and speech based systems will serve as illustration of a mobile authentication application. A novel signal adaptive supervisor, based on the input biometric signal quality is evaluated. Experimental results on data collected from mobile telephones are reported demonstrating the benefits of the proposed scheme. © 2003 IEEE.
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| 5. |
- Bigun, Josef, et al.
(författare)
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Orientation fields filtering by derivates of a Gaussian
- 2003
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Ingår i: Image Analysis. - Berlin : Springer. - 3540406018 ; , s. 307-313, s. 19-27
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Bokkapitel (refereegranskat)abstract
- We suggest a set of complex differential operators, symmetry derivatives, that can be used for matching and pattern recognition. We present results on the invariance properties of these. These show that all orders of symmetry derivatives of Gaussians yield a remarkable invariance : they are obtained by replacing the original differential polynomial with the same polynomial but using ordinary scalars. Moreover, these functions are closed under convolution and they are invariant to the Fourier transform. The revealed properties have practical consequences for local orientation based feature extraction. This is shown by two applications: i) tracking markers in vehicle tests ii) alignment of fingerprints.
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| 6. |
- Bigun, Josef, 1961-, et al.
(författare)
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Recognition by symmetry derivatives and the generalized structure tensor
- 2004
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Ingår i: IEEE Transactions on Pattern Analysis and Machine Intelligence. - Los Alamitos, USA : IEEE Computer Society. - 0162-8828 .- 1939-3539. ; 26:12, s. 1590-1605
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Tidskriftsartikel (refereegranskat)abstract
- We suggest a set of complex differential operators that can be used to produce and filter dense orientation (tensor) fields for feature extraction, matching, and pattern recognition. We present results on the invariance properties of these operators, that we call symmetry derivatives. These show that, in contrast to ordinary derivatives, all orders of symmetry derivatives of Gaussians yield a remarkable invariance: they are obtained by replacing the original differential polynomial with the same polynomial, but using ordinary coordinates x and y corresponding to partial derivatives. Moreover, the symmetry derivatives of Gaussians are closed under the convolution operator and they are invariant to the Fourier transform. The equivalent of the structure tensor, representing and extracting orientations of curve patterns, had previously been shown to hold in harmonic coordinates in a nearly identical manner. As a result, positions, orientations, and certainties of intricate patterns, e.g., spirals, crosses, parabolic shapes, can be modeled by use of symmetry derivatives of Gaussians with greater analytical precision as well as computational efficiency. Since Gaussians and their derivatives are utilized extensively in image processing, the revealed properties have practical consequences for local orientation based feature extraction. The usefulness of these results is demonstrated by two applications:tracking cross markers in long image sequences from vehicle crash tests andalignment of noisy fingerprints.
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| 7. |
- Bigun, Josef, et al.
(författare)
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Symmetry derivatives of Gaussians illustrated by cross tracking
- 2001
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- We propose a family of complex differential operators, symmetry derivatives, for pattern recognition in images. We present three theorems on their properties as applied to Gaussians. These show that all orders of symmetry derivatives of Gaussians yield compact expressions obtained by replacing the original differential polynomial with an ordinary polynomial. Just like Gaussians, the symmetry derivatives of Gaussians are (form) invariant to Fourier transform, that is they are rescaled versions of the original. As a result, the symmetry derivatives of Gaussians are closed under the convolution operator, i.e. they map on a member of the family when convolved with each other. Since Gaussians are utilized extensively in image processing, the revealed properties have practical consequences, e.g. when designing filters and filtering schemes that are unbiased w.r.t. orientation (isotropic). A use of these results is illustrated by an application: tracking the cross markers in long image sequences from vehicle crash tests. The implementation and the results of this application are discussed in terms of the theorems presented, along with conclusions.
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| 8. |
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Biometric authentication : International ECCV 2002 Workshop, Copenhagen, Denmark, June 1, 2002 : proceedings
- 2002
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Proceedings (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- This book constitutes the refereed proceedings of the International Workshop on Biometric Authentication held in Copenhagen, Denmark, in June 2001 as a satellite event of ECCV 2002.The 19 revised full papers presented were carefully reviewed. The papers are organized in topical sections on face recognition, fingerprint recognition, psychology and biometrics, face detection and localization, gait and signature recognition, and classifiers for recognition.
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| 9. |
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| 10. |
- Fierrez-Aguilar, Julian, et al.
(författare)
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Kernel-based multimodal biometric verification using quality signals
- 2004
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Ingår i: Proceedings of SPIE. - : SPIE. ; , s. 544-554
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A novel kernel-based fusion strategy is presented. It is based on SVM classifiers, trade-off coefficients introduced in the standard SVM training and testing procedures, and quality measures of the input biometric signals. Experimental results on a prototype application based on voice and fingerprint traits are reported. The benefits of using the two modalities as compared to only using one of them are revealed. This is achieved by using a novel experimental procedure in which multi-modal verification performance tests are compared with multi-probe tests of the individual subsystems. Appropriate selection of the parameters of the proposed quality-based scheme leads to a quality-based fusion scheme outperforming the raw fusion strategy without considering quality signals. In particular, a relative improvement of 18% is obtained for small SVM training set size by using only fingerprint quality labels.
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