1,775 research outputs found
CHORUS Deliverable 2.2: Second report - identification of multi-disciplinary key issues for gap analysis toward EU multimedia search engines roadmap
After addressing the state-of-the-art during the first year of Chorus and establishing the existing landscape in
multimedia search engines, we have identified and analyzed gaps within European research effort during our second year.
In this period we focused on three directions, notably technological issues, user-centred issues and use-cases and socio-
economic and legal aspects. These were assessed by two central studies: firstly, a concerted vision of functional breakdown
of generic multimedia search engine, and secondly, a representative use-cases descriptions with the related discussion on
requirement for technological challenges. Both studies have been carried out in cooperation and consultation with the
community at large through EC concertation meetings (multimedia search engines cluster), several meetings with our
Think-Tank, presentations in international conferences, and surveys addressed to EU projects coordinators as well as
National initiatives coordinators. Based on the obtained feedback we identified two types of gaps, namely core
technological gaps that involve research challenges, and “enablers”, which are not necessarily technical research
challenges, but have impact on innovation progress. New socio-economic trends are presented as well as emerging legal
challenges
A Speaker Verification Backend with Robust Performance across Conditions
In this paper, we address the problem of speaker verification in conditions
unseen or unknown during development. A standard method for speaker
verification consists of extracting speaker embeddings with a deep neural
network and processing them through a backend composed of probabilistic linear
discriminant analysis (PLDA) and global logistic regression score calibration.
This method is known to result in systems that work poorly on conditions
different from those used to train the calibration model. We propose to modify
the standard backend, introducing an adaptive calibrator that uses duration and
other automatically extracted side-information to adapt to the conditions of
the inputs. The backend is trained discriminatively to optimize binary
cross-entropy. When trained on a number of diverse datasets that are labeled
only with respect to speaker, the proposed backend consistently and, in some
cases, dramatically improves calibration, compared to the standard PLDA
approach, on a number of held-out datasets, some of which are markedly
different from the training data. Discrimination performance is also
consistently improved. We show that joint training of the PLDA and the adaptive
calibrator is essential -- the same benefits cannot be achieved when freezing
PLDA and fine-tuning the calibrator. To our knowledge, the results in this
paper are the first evidence in the literature that it is possible to develop a
speaker verification system with robust out-of-the-box performance on a large
variety of conditions
Audio segmentation-by-classification approach based on factor analysis in broadcast news domain
This paper studies a novel audio segmentation-by-classification approach based on factor analysis. The proposed technique compensates the within-class variability by using class-dependent factor loading matrices and obtains the scores by computing the log-likelihood ratio for the class model to a non-class model over fixed-length windows. Afterwards, these scores are smoothed to yield longer contiguous segments of the same class by means of different back-end systems. Unlike previous solutions, our proposal does not make use of specific acoustic features and does not need a hierarchical structure. The proposed method is applied to segment and classify audios coming from TV shows into five different acoustic classes: speech, music, speech with music, speech with noise, and others. The technique is compared to a hierarchical system with specific acoustic features achieving a significant error reduction
PICES Press, Vol. 16, No. 1, January 2008
â—ľPICES Science in 2007 (pdf, 0.1 Mb)
â—ľ2007 Wooster Award (pdf, 0.1 Mb)
â—ľFUTURE - A milestone reached but our task is not done (pdf, < 0.1 Mb)
â—ľInternational symposium on "Reproductive and Recruitment Processes of Exploited Marine Fish Stocks" (pdf, 0.1 Mb)
â—ľRecent results of the micronekton sampling inter-calibration experiment (pdf, 0.1 Mb)
â—ľ2007 PICES workshop on "Measuring and monitoring primary productivity in the North Pacific" (pdf, 0.1 Mb)
â—ľ2007 Harmful Algal Bloom Section annual workshop events (pdf, 0.1 Mb)
â—ľA global approach for recovery and sustainability of marine resources in Large Marine Ecosystems (pdf, 0.3 Mb)
â—ľHighlights of the PICES Sixteenth Annual Meeting (pdf, 0.4 Mb)
â—ľOcean acidification of the North Pacific Ocean (pdf, 0.3 Mb)
â—ľWorkshop on NE Pacific Coastal Ecosystems (2008 Call for Salmon Survival Forecasts) (pdf, 0.1 Mb)
â—ľThe state of the western North Pacific in the first half of 2007 (pdf, 0.4 Mb)
â—ľPICES Calendar (pdf, 0.4 Mb)
â—ľThe Bering Sea: Current status and recent events (pdf, 0.3 Mb)
â—ľPICES Interns (pdf, 0.3 Mb)
â—ľRecent trends in waters of the subarctic NE Pacific (pdf, 0.3 Mb)
â—ľElection results at PICES (pdf, 0.2 Mb)
â—ľA new PICES award for monitoring and data management activities (pdf, < 0.1 Mb
Calibration of score based likelihood ratio estimation in automated forensic facial image comparison
Calibration of score based likelihood ratio estimation in automated forensic facial image comparison
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