1,519 research outputs found
A Survey on Ear Biometrics
Recognizing people by their ear has recently received significant attention in the literature. Several reasons account for this trend: first, ear recognition does not suffer from some problems associated with other non contact biometrics, such as face recognition; second, it is the most promising candidate for combination with the face in the context of multi-pose face recognition; and third, the ear can be used for human recognition in surveillance videos where the face may be occluded completely or in part. Further, the ear appears to degrade little with age. Even though, current ear detection and recognition systems have reached a certain level of maturity, their success is limited to controlled indoor conditions. In addition to variation in illumination, other open research problems include hair occlusion; earprint forensics; ear symmetry; ear classification; and ear individuality. This paper provides a detailed survey of research conducted in ear detection and recognition. It provides an up-to-date review of the existing literature revealing the current state-of-art for not only those who are working in this area but also for those who might exploit this new approach. Furthermore, it offers insights into some unsolved ear recognition problems as well as ear databases available for researchers
Automatic object classification for surveillance videos.
PhDThe recent popularity of surveillance video systems, specially located in urban
scenarios, demands the development of visual techniques for monitoring purposes.
A primary step towards intelligent surveillance video systems consists on automatic
object classification, which still remains an open research problem and the keystone
for the development of more specific applications.
Typically, object representation is based on the inherent visual features. However,
psychological studies have demonstrated that human beings can routinely categorise
objects according to their behaviour. The existing gap in the understanding
between the features automatically extracted by a computer, such as appearance-based
features, and the concepts unconsciously perceived by human beings but
unattainable for machines, or the behaviour features, is most commonly known
as semantic gap. Consequently, this thesis proposes to narrow the semantic gap
and bring together machine and human understanding towards object classification.
Thus, a Surveillance Media Management is proposed to automatically detect and
classify objects by analysing the physical properties inherent in their appearance
(machine understanding) and the behaviour patterns which require a higher level of
understanding (human understanding). Finally, a probabilistic multimodal fusion
algorithm bridges the gap performing an automatic classification considering both
machine and human understanding.
The performance of the proposed Surveillance Media Management framework
has been thoroughly evaluated on outdoor surveillance datasets. The experiments
conducted demonstrated that the combination of machine and human understanding
substantially enhanced the object classification performance. Finally, the inclusion
of human reasoning and understanding provides the essential information to bridge
the semantic gap towards smart surveillance video systems
Predictive biometrics: A review and analysis of predicting personal characteristics from biometric data
Interest in the exploitation of soft biometrics information has continued to develop over the last decade or so. In comparison with traditional biometrics, which focuses principally on person identification, the idea of soft biometrics processing is to study the utilisation of more general information regarding a system user, which is not necessarily unique. There are increasing indications that this type of data will have great value in providing complementary information for user authentication. However, the authors have also seen a growing interest in broadening the predictive capabilities of biometric data, encompassing both easily definable characteristics such as subject age and, most recently, `higher level' characteristics such as emotional or mental states. This study will present a selective review of the predictive capabilities, in the widest sense, of biometric data processing, providing an analysis of the key issues still adequately to be addressed if this concept of predictive biometrics is to be fully exploited in the future
Multiple classifiers in biometrics. Part 2: Trends and challenges
The present paper is Part 2 in this series of two papers. In Part 1 we provided an introduction to Multiple Classifier Systems (MCS) with a focus into the fundamentals: basic nomenclature, key elements, architecture, main methods, and prevalent theory and framework. Part 1 then overviewed the application of MCS to the particular field of multimodal biometric person authentication in the last 25 years, as a prototypical area in which MCS has resulted in important achievements. Here in Part 2 we present in more technical detail recent trends and developments in MCS coming from multimodal biometrics that incorporate context information in an adaptive way. These new MCS architectures exploit input quality measures and pattern-specific particularities that move apart from general population statistics, resulting in robust multimodal biometric systems. Similarly as in Part 1, methods here are described in a general way so they can be applied to other information fusion problems as well. Finally, we also discuss here open challenges in biometrics in which MCS can play a key roleThis work was funded by projects CogniMetrics (TEC2015-70627-R)
from MINECO/FEDER and RiskTrakc (JUST-2015-JCOO-AG-1). Part of
this work was conducted during a research visit of J.F. to Prof. Ludmila
Kuncheva at Bangor University (UK) with STSM funding from COST CA16101 (MULTI-FORESEE
Quality-Based Conditional Processing in Multi-Biometrics: Application to Sensor Interoperability
As biometric technology is increasingly deployed, it will be common to
replace parts of operational systems with newer designs. The cost and
inconvenience of reacquiring enrolled users when a new vendor solution is
incorporated makes this approach difficult and many applications will require
to deal with information from different sources regularly. These
interoperability problems can dramatically affect the performance of biometric
systems and thus, they need to be overcome. Here, we describe and evaluate the
ATVS-UAM fusion approach submitted to the quality-based evaluation of the 2007
BioSecure Multimodal Evaluation Campaign, whose aim was to compare fusion
algorithms when biometric signals were generated using several biometric
devices in mismatched conditions. Quality measures from the raw biometric data
are available to allow system adjustment to changing quality conditions due to
device changes. This system adjustment is referred to as quality-based
conditional processing. The proposed fusion approach is based on linear
logistic regression, in which fused scores tend to be log-likelihood-ratios.
This allows the easy and efficient combination of matching scores from
different devices assuming low dependence among modalities. In our system,
quality information is used to switch between different system modules
depending on the data source (the sensor in our case) and to reject channels
with low quality data during the fusion. We compare our fusion approach to a
set of rule-based fusion schemes over normalized scores. Results show that the
proposed approach outperforms all the rule-based fusion schemes. We also show
that with the quality-based channel rejection scheme, an overall improvement of
25% in the equal error rate is obtained.Comment: Published at IEEE Transactions on Systems, Man, and Cybernetics -
Part A: Systems and Human
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