94,092 research outputs found
Audio and video processing for automatic TV advertisement detection
As a partner in the Centre for Digital Video Processing, the Visual Media Processing Group at Dublin City University conducts research and development in the area of digital video management. The current stage of development is demonstrated on our Web-based digital video system called Físchlár [1,2], which provides for efficient recording,
analyzing, browsing and viewing of digitally captured television programmes. In order to make the browsing of
programme material more efficient, users have requested the option of automatically deleting advertisement breaks.
Our initial work on this task focused on locating ad-breaks by detecting patterns of silent black frames which separate
individual advertisements and/or complete ad-breaks in most commercial TV stations. However, not all TV stations use
silent, black frames to flag ad-breaks. We therefore decided to attempt to detect advertisements using the rate of shot cuts in the digitised TV signal. This paper describes the implementation and performance of both methods of ad-break
detection
On the Detection and Recognition of Television Commercials
TV commercials are interesting in many respects: advertisers and psychologists are interested in their influence on human purchasing habits, while parents might be interested in shielding their children from their influence. In this paper, two methods for detecting and extracting commercials in digital videos are described. The first method is based on statistics of measurable features and enables the detection of commercial blocks within TV broadcasts. The second method performs detection and recognition of known commercials with high accuracy. Finally, we show how both approaches can be combined into a self-learning system. Our experimental results underline the practicality of the methods
Method for Real-Time Signal Selection for Passive Coherent Location Systems
Passive coherent location (PCL) systems use signals of opportunity to perform traditional radar detection, targeting, and tracking functions. Traditionally these signals include FM radio, digital TV, GSM, and GPS because of their availability in most urban environments. A benefit of having an abundance of signals is the ability to choose which of those best meet the desired system intentions. For example, one may want to choose a digital TV signal over an FM radio signal due to its range resolution characteristics. This work presents a novel algorithm for characterizing commercial signals for use in a PCL system. By analyzing each signal\u27s ambiguity function in terms of amplitude, transmitter geometry, range and Doppler resolution, and sidelobe levels, a comparative evaluation can be made to decide which signals are best suited for an intended radar function. In addition, this research shows that multiple signals can be combined in the detection process to increase the probability of detection over that of a single signal. Finally, this research investigates the geometric considerations for PCL systems in terms of bistatic radar geometry. The results show zones of linear and non-linear relationships between time delay, range, and Doppler frequency
The Físchlár digital video recording, analysis, and browsing system
In digital video indexing research area an important technique is called shot boundary detection which automatically segments long video material into camera shots using content-based analysis of video. We have been working on developing various shot boundary detection and representative frame selection techniques to automatically index encoded video stream and provide the end users with video browsing/navigation feature. In this paper we describe a demonstrator digital video system that allows the user to record a TV broadcast programme to MPEG-1 file format and to easily browse and playback the file content online. The system incorporates the shot boundary detection and representative frame selection techniques we have developed and has become a full-featured digital video system that not only demonstrates any further techniques we will develop, but also obtains users’ video browsing behaviour. At the moment the system has a real-user base of about a hundred people and we are closely monitoring how they use the video browsing/navigation feature which the system provides
Cognitive Radio Networks: Realistic or Not?
A large volume of research has been conducted in the cognitive radio (CR)
area the last decade. However, the deployment of a commercial CR network is yet
to emerge. A large portion of the existing literature does not build on real
world scenarios, hence, neglecting various important interactions of the
research with commercial telecommunication networks. For instance, a lot of
attention has been paid to spectrum sensing as the front line functionality
that needs to be completed in an efficient and accurate manner to enable an
opportunistic CR network architecture. This is necessary to detect the
existence of spectrum holes without which no other procedure can be fulfilled.
However, simply sensing (cooperatively or not) the energy received from a
primary transmitter cannot enable correct dynamic spectrum access. For example,
the low strength of a primary transmitter's signal does not assure that there
will be no interference to a nearby primary receiver. In addition, the presence
of a primary transmitter's signal does not mean that CR network users cannot
access the spectrum since there might not be any primary receiver in the
vicinity. Despite the existing elegant and clever solutions to the DSA problem
no robust, implementable scheme has emerged. In this paper, we challenge the
basic premises of the proposed schemes. We further argue that addressing the
technical challenges we face in deploying robust CR networks can only be
achieved if we radically change the way we design their basic functionalities.
In support of our argument, we present a set of real-world scenarios, inspired
by realistic settings in commercial telecommunications networks, focusing on
spectrum sensing as a basic and critical functionality in the deployment of
CRs. We use these scenarios to show why existing DSA paradigms are not amenable
to realistic deployment in complex wireless environments.Comment: Work in progres
Update on Laboratory Diagnosis and Epidemiology of \u3cem\u3eTrichomonas vaginalis\u3c/em\u3e: You Can Teach an “Old” Dog “New” Trichs
Past viewpoints on Trichomonas vaginalis infection have characterized the associated clinical disease as a “nuisance” condition, with affected demographics largely being older African American females residing in urban centers. The advent of commercial molecular assays specific for T. vaginalis has offered a new outlook on trichomoniasis. Within high-prevalence sexually transmitted infection populations, parasite distribution is not localized to specific population centers, and T. vaginalis prevalence is elevated among both younger and older age groups. Adaptation of these molecular assays can additionally facilitate male screening and subsequent epidemiologic characterization. These findings, combined with associations between T. vaginalis infection and human immunodeficiency virus (HIV) acquisition/transmission and persistent human papillomavirus infection, support consideration of the expansion of T. vaginalis screening efforts in the realms of clinical practice and public health
CHORUS Deliverable 3.4: Vision Document
The goal of the CHORUS Vision Document is to create a high level vision on audio-visual search engines in order to give guidance to the future R&D work in this area and to highlight trends and challenges in this domain. The vision of CHORUS is strongly connected to the CHORUS Roadmap Document (D2.3). A concise document integrating the outcomes of the two deliverables will be prepared for the end of the project (NEM Summit)
Field test of quantum key distribution in the Tokyo QKD Network
A novel secure communication network with quantum key distribution in a
metropolitan area is reported. Different QKD schemes are integrated to
demonstrate secure TV conferencing over a distance of 45km, stable long-term
operation, and application to secure mobile phones.Comment: 21 pages, 19 figure
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