102 research outputs found
An Advanced Technique for User Identification Using Partial Fingerprint
User identification is a very interesting and
complex task. Invasive biometrics is based on traits
uniqueness and immutability over time. In forensic field,
fingerprints have always been considered an essential
element for personal recognition. The traditional issue is
focused on full fingerprint images matching. In this paper an
advanced technique for personal recognition based on
partial fingerprint is proposed. This system is based on
fingerprint local analysis and micro-features, endpoints and
bifurcations, extraction. The proposed approach starts from
minutiae extraction from a partial fingerprint image and
ends with the final matching score between fingerprint pairs.
The computation of likelihood ratios in fingerprint
identification is computed by trying every possible
overlapping of the partial image with complete image. The
first experimental results conducted on the PolyU (Hong
Kong Polytechnic University) free database show an
encouraging performance in terms of identification
accuracy
An Embedded Biometric Sensor for Ubiquitous Authentication
Communication networks and distributed technologies
move people towards the era of ubiquitous computing. An
ubiquitous environment needs many authentication sensors for
users recognition, in order to provide a secure infrastructure for
both user access to resources and services and information
management. Today the security requirements must ensure
secure and trusted user information to protect sensitive data
resource access and they could be used for user traceability inside
the platform. Conventional authentication systems, based on
username and password, are in crisis since they are not able to
guarantee a suitable security level for several applications.
Biometric authentication systems represent a valid alternative to
the conventional authentication systems providing a flexible einfrastructure
towards an integrated solution supporting the
requirement for improved inter-organizational functionality. In
this work the study and the implementation of a fingerprintsbased
embedded biometric system is proposed. Typical strategies
implemented in Identity Management Systems could be useful to
protect biometric information. The proposed sensor can be seen
as a self-contained sensor: it performs the all elaboration steps on
board, a necessary requisite to strengthen security, so that
sensible data are securely managed and stored inside the sensor,
without any data leaking out. The sensor has been prototyped via
an FPGA-based platform achieving fast execution time and a
good final throughput. Resources used, elaboration times of the
sensor are reported. Finally, recognition rates of the proposed
embedded biometric sensor have been evaluated considering
three different databases: the FVC2002 reference database, the
CSAI/Biometrika proprietary database, and the CSAI/Secugen
proprietary database. The best achieved FAR and FRR indexes
are respectively 1.07% and 8.33%, with an elaboration time of
183.32 ms and a working frequency of 22.5 MHz
Embedded Knowledge-based Speech Detectors for Real-Time Recognition Tasks
Speech recognition has become common in many application domains, from dictation systems for professional practices to vocal user interfaces for people with disabilities or hands-free system control. However, so far the performance of automatic speech recognition (ASR) systems are comparable to human speech recognition (HSR) only under very strict working conditions, and in general much lower. Incorporating acoustic-phonetic knowledge into ASR design has been proven a viable approach to raise ASR accuracy. Manner of articulation attributes such as vowel, stop, fricative, approximant, nasal, and silence are examples of such knowledge. Neural networks have already been used successfully as detectors for manner of articulation attributes starting from representations of speech signal frames. In this paper, the full system implementation is described. The system has a first stage for MFCC extraction followed by a second stage implementing a sinusoidal based multi-layer perceptron for speech event classification. Implementation details over a Celoxica RC203 board are give
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