207 research outputs found
Multiple constraints to compute optical flow
The computation of the optical flow field from an image sequence requires the definition of constraints on the temporal change of image features. In this paper, we consider the implications of using multiple constraints in the computational schema. In the first step, it is shown that differential constraints correspond to an implicit feature tracking. Therefore, the best results (either in terms of measurement accuracy, and speed in the computation) are obtained by selecting and applying the constraints which are best “tuned” to the particular image feature under consideration. Considering also multiple image points not only allows us to obtain a (locally) better estimate of the velocity field, but also to detect erroneous measurements due to discontinuities in the velocity field. Moreover, by hypothesizing a constant acceleration motion model, also the derivatives of the optical flow are computed. Several experiments are presented from real image sequences
On the use of SIFT features for face authentication
Several pattern recognition and classification techniques
have been applied to the biometrics domain. Among them,
an interesting technique is the Scale Invariant Feature
Transform (SIFT), originally devised for object recognition.
Even if SIFT features have emerged as a very powerful image
descriptors, their employment in face analysis context
has never been systematically investigated.
This paper investigates the application of the SIFT approach
in the context of face authentication. In order to determine
the real potential and applicability of the method,
different matching schemes are proposed and tested using
the BANCA database and protocol, showing promising results
Understanding critical factors in gender recognition
Gender classification is a task of paramount importance in face recognition research, and it is potentially useful in a large set of applications. In this paper we investigate the gender classification problem by an extended empirical analysis on the Face Recognition Grand Challenge version 2.0 dataset (FRGC2.0). We propose challenging experimental protocols over the dimensions of FRGC2.0 – i.e., subject, face expression, race, controlled or uncontrolled environment. We evaluate our protocols with respect to several classification algorithms, and processing different types of features, like Gabor and LBP. Our results show that
gender classification is independent from factors like the race of the subject, face expressions, and variations of controlled illumination conditions. We also report that Gabor features seem to be more robust than LBPs in the case of uncontrolled environment
Robust multi-modal and multi-unit feature level fusion of face and iris biometrics
Multi-biometrics has recently emerged as a mean of more robust and effcient
personal verification and identification. Exploiting information from multiple
sources at various levels i.e., feature, score, rank or decision, the false acceptance
and rejection rates can be considerably reduced. Among all, feature level fusion
is relatively an understudied problem. This paper addresses the feature level
fusion for multi-modal and multi-unit sources of information. For multi-modal
fusion the face and iris biometric traits are considered, while the multi-unit fusion
is applied to merge the data from the left and right iris images. The proposed
approach computes the SIFT features from both biometric sources, either multi-
modal or multi-unit. For each source, the extracted SIFT features are selected via
spatial sampling. Then these selected features are finally concatenated together
into a single feature super-vector using serial fusion. This concatenated feature
vector is used to perform classification.
Experimental results from face and iris standard biometric databases are
presented. The reported results clearly show the performance improvements in
classification obtained by applying feature level fusion for both multi-modal and
multi-unit biometrics in comparison to uni-modal classification and score level
fusion
Feature Level Fusion of Face and Fingerprint Biometrics
The aim of this paper is to study the fusion at feature extraction level for
face and fingerprint biometrics. The proposed approach is based on the fusion
of the two traits by extracting independent feature pointsets from the two
modalities, and making the two pointsets compatible for concatenation.
Moreover, to handle the problem of curse of dimensionality, the feature
pointsets are properly reduced in dimension. Different feature reduction
techniques are implemented, prior and after the feature pointsets fusion, and
the results are duly recorded. The fused feature pointset for the database and
the query face and fingerprint images are matched using techniques based on
either the point pattern matching, or the Delaunay triangulation. Comparative
experiments are conducted on chimeric and real databases, to assess the actual
advantage of the fusion performed at the feature extraction level, in
comparison to the matching score level.Comment: 6 pages, 7 figures, conferenc
Responsabilita ed irresponsabilita sociale d'impresa in materia di diritti umani nei paesi avanzati
La presente tesi si pone come obiettivo quello di analizzare i comportamenti responsabili ed irresponsabili da parte delle grandi imprese dei paesi avanzati. Nello specifico mira a capire se esiste una relazione tra l’adozione di politiche di Responsabilità sociale d’impresa (RSI) da parte delle aziende ed il loro coinvolgimento in abusi di diritti umani. Inoltre analizza la situazione rispetto ai paesi in cui le aziende pongono in essere i loro abusi
Visual Surveillance and Biometrics: Practices, Challenges, and Possibilities
Visual surveillance is the latest paradigm for social security through machine intelligence. It includes the use of visual data captured by infrared sensors or visible-light cameras mounted in cars, corridors, traffic signals etc. Visual surveillance facilitates the classification of human behavior, crowd activity, and gesture analysis to achieve application-specific objectivesinfo:eu-repo/semantics/publishedVersio
STUDIO PROCESSI AZIENDALI LEGATI AI SERVIZI PER STARTUP DI M31
Il candidato verrĂ integrato nella sede istituzionale di M31 a Monselice (PD), presso Villa Duodo, ove operano i manager della holding ed il personale amministrativo.
Il candidato prenderĂ contatto con i responsabili delle principali funzioni dirigenziali di M31 al fine di comprendere prima e mappare poi i processi e servizi attraverso i quali M31 interagisce con le proprie partecipate.
E' inoltre richiesta l'identificazione dei KPI che guidano l'attivitĂ quotidiana di M31, un'analisi di costing sui singoli processi individuati.
Infine, per rendere piĂą efficace il processo di Selezione degli Investimenti in M31, il candidato dovrĂ analizzare l'introduzione di una piattaforma per la gestione delle opportunitĂ di investimento che giungono in input ad M31
- …