4,545 research outputs found

    CHORUS Deliverable 2.2: Second report - identification of multi-disciplinary key issues for gap analysis toward EU multimedia search engines roadmap

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    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 framework for automatic semantic video annotation

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    The rapidly increasing quantity of publicly available videos has driven research into developing automatic tools for indexing, rating, searching and retrieval. Textual semantic representations, such as tagging, labelling and annotation, are often important factors in the process of indexing any video, because of their user-friendly way of representing the semantics appropriate for search and retrieval. Ideally, this annotation should be inspired by the human cognitive way of perceiving and of describing videos. The difference between the low-level visual contents and the corresponding human perception is referred to as the ‘semantic gap’. Tackling this gap is even harder in the case of unconstrained videos, mainly due to the lack of any previous information about the analyzed video on the one hand, and the huge amount of generic knowledge required on the other. This paper introduces a framework for the Automatic Semantic Annotation of unconstrained videos. The proposed framework utilizes two non-domain-specific layers: low-level visual similarity matching, and an annotation analysis that employs commonsense knowledgebases. Commonsense ontology is created by incorporating multiple-structured semantic relationships. Experiments and black-box tests are carried out on standard video databases for action recognition and video information retrieval. White-box tests examine the performance of the individual intermediate layers of the framework, and the evaluation of the results and the statistical analysis show that integrating visual similarity matching with commonsense semantic relationships provides an effective approach to automated video annotation

    Learning midlevel image features for natural scene and texture classification

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    This paper deals with coding of natural scenes in order to extract semantic information. We present a new scheme to project natural scenes onto a basis in which each dimension encodes statistically independent information. Basis extraction is performed by independent component analysis (ICA) applied to image patches culled from natural scenes. The study of the resulting coding units (coding filters) extracted from well-chosen categories of images shows that they adapt and respond selectively to discriminant features in natural scenes. Given this basis, we define global and local image signatures relying on the maximal activity of filters on the input image. Locally, the construction of the signature takes into account the spatial distribution of the maximal responses within the image. We propose a criterion to reduce the size of the space of representation for faster computation. The proposed approach is tested in the context of texture classification (111 classes), as well as natural scenes classification (11 categories, 2037 images). Using a common protocol, the other commonly used descriptors have at most 47.7% accuracy on average while our method obtains performances of up to 63.8%. We show that this advantage does not depend on the size of the signature and demonstrate the efficiency of the proposed criterion to select ICA filters and reduce the dimensio

    A comparative evaluation of interactive segmentation algorithms

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    In this paper we present a comparative evaluation of four popular interactive segmentation algorithms. The evaluation was carried out as a series of user-experiments, in which participants were tasked with extracting 100 objects from a common dataset: 25 with each algorithm, constrained within a time limit of 2 min for each object. To facilitate the experiments, a “scribble-driven” segmentation tool was developed to enable interactive image segmentation by simply marking areas of foreground and background with the mouse. As the participants refined and improved their respective segmentations, the corresponding updated segmentation mask was stored along with the elapsed time. We then collected and evaluated each recorded mask against a manually segmented ground truth, thus allowing us to gauge segmentation accuracy over time. Two benchmarks were used for the evaluation: the well-known Jaccard index for measuring object accuracy, and a new fuzzy metric, proposed in this paper, designed for measuring boundary accuracy. Analysis of the experimental results demonstrates the effectiveness of the suggested measures and provides valuable insights into the performance and characteristics of the evaluated algorithms

    Forensic Data Properties of Digital Signature BDOC and ASiC-E Files on Classic Disk Drives

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    KĂ€esolevas magistritöös vaadeldakse BDOC ja ASiC-E digitaalselt allkirjastatud dokumendikonteinerite sisu ning kirjeldatakse nende huvipakkuvaid omadusi. Teatava hulga nĂ€idiskonteinerite vaatlemise jĂ€rel pakub autor vĂ€lja faili pĂ€ise ja faili jaluse kombinatsiooni (signatuuri), mis oluliselt parandab nimetatud failide kustutatud olekust sihitud taastamist kĂŒlgnevatest klastritest NTFS vormindatud tihendamata kettal, vĂ”ttes arvesse klassikalise kĂ”vaketta geomeetriat. Ühtlasi kirjeldab autor kohtuekspertiisi koha pealt tĂ€hendust omavaid andmeid ZIP kohaliku faili pĂ€ises ja keskkataloogi kirjes, XML signatuuris ja ASN.1 kodeeritud kihtides ning nende kĂ€ttesaamise algoritmi. Nendele jĂ€reldustele tuginedes loob autor Phytoni skripte ja viib lĂ€bi mitmeid teste failide taastamiseks faili signatuuri jĂ€rgi ning huvipakkuvate andmete vĂ€ljavĂ”tmiseks. Teste viiakse lĂ€bi teatava valiku failide ĂŒle ja tulemusi vĂ”rreldakse mitme kohtuekspertiisis laialt kasutatava peavoolu töökeskkonnaga, samuti mĂ”ningate andmetaaste tööriistadega. LĂ”puks testitakse magistritöö kĂ€igus pakutud digitaalselt allkirjastatud dokumentide taastamiseks mĂ”eldud signatuuri ja andmete vĂ€ljavĂ”tmise algoritmi suurel hulgal avalikust dokumendiregistrist pĂ€rit kehtivate dokumentidega, mis saadi kĂ€tte spetsiaalselt selleks kirjutatud veebirobotiga. Nimetatud teste viiakse lĂ€bi dokumentide ĂŒle, mille hulgas on nii digitaalselt allkirjastatud dokumente kui ka teisi, nendega struktuurilt sarnaseid dokumente.This thesis reviews the contents and observes certain properties of digitally signed documents of BDOC and ASiC-E container formats. After reviewing a set of sample containers, the author comes up with a header and footer combination (signature) significantly improving pinpointed carving-based recovery of those files from a deleted state on NTFS formatted uncompressed volumes in contiguous clusters, taking into account the geometry of classic disk drives. The author also describes forensically meaningful attributive data found in ZIP Headers and Central Directory, XML signatures as well as embedded ASN.1 encoded data of the sample files and suggests an algorithm for the extraction of such data. Based on these findings, the author creates scripts in Python and executes a series of tests for file carving and extraction of attributive data. These tests are run over the samples placed into unallocated clusters and the results are compared to several mainstream commercial forensic examination suites as well as some popular data recovery tools. Finally, the author web-scrapes a large number of real-life documents from a government agency’s public document registry. The carving signature and the data-extractive algorithm are thereafter applied on a larger scale and in an environment competitively supplemented with structurally similar containers

    NATURAL LANGUAGE DOCUMENTS: INDEXING AND RETRIEVAL IN AN INFORMATION SYSTEM

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    A steadily increasing number of natural language (NL) documents are handled in information systems. Most of these documents typically contain some formatted data, which we call strong database data, and additionally some unformatted data, i.e., free text. The task of a modern information system is to characterize such unformatted (text) data automatically and, in doing so, to support the user in storing and retrieving natural language documents. The retrieval of natural language documents is a fuzzy process because the user will formulate fuzzy queries unless he uses some strong search keys. Retrieval of natural language documents can be facilitated with natural language queries; that is, with searches based on natural language text comparisons

    CONTENT BASED RETRIEVAL OF LECTURE VIDEO REPOSITORY: LITERATURE REVIEW

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    Multimedia has a significant role in communicating the information and a large amount of multimedia repositories make the browsing, retrieval and delivery of video contents. For higher education, using video as a tool for learning and teaching through multimedia application is a considerable promise. Many universities adopt educational systems where the teacher lecture is video recorded and the video lecture is made available to students with minimum post-processing effort. Since each video may cover many subjects, it is critical for an e-Learning environment to have content-based video searching capabilities to meet diverse individual learning needs. The present paper reviewed 120+ core research article on the content based retrieval of the lecture video repositories hosted on cloud by government academic and research organization of India

    Content Recognition and Context Modeling for Document Analysis and Retrieval

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    The nature and scope of available documents are changing significantly in many areas of document analysis and retrieval as complex, heterogeneous collections become accessible to virtually everyone via the web. The increasing level of diversity presents a great challenge for document image content categorization, indexing, and retrieval. Meanwhile, the processing of documents with unconstrained layouts and complex formatting often requires effective leveraging of broad contextual knowledge. In this dissertation, we first present a novel approach for document image content categorization, using a lexicon of shape features. Each lexical word corresponds to a scale and rotation invariant local shape feature that is generic enough to be detected repeatably and is segmentation free. A concise, structurally indexed shape lexicon is learned by clustering and partitioning feature types through graph cuts. Our idea finds successful application in several challenging tasks, including content recognition of diverse web images and language identification on documents composed of mixed machine printed text and handwriting. Second, we address two fundamental problems in signature-based document image retrieval. Facing continually increasing volumes of documents, detecting and recognizing unique, evidentiary visual entities (\eg, signatures and logos) provides a practical and reliable supplement to the OCR recognition of printed text. We propose a novel multi-scale framework to detect and segment signatures jointly from document images, based on the structural saliency under a signature production model. We formulate the problem of signature retrieval in the unconstrained setting of geometry-invariant deformable shape matching and demonstrate state-of-the-art performance in signature matching and verification. Third, we present a model-based approach for extracting relevant named entities from unstructured documents. In a wide range of applications that require structured information from diverse, unstructured document images, processing OCR text does not give satisfactory results due to the absence of linguistic context. Our approach enables learning of inference rules collectively based on contextual information from both page layout and text features. Finally, we demonstrate the importance of mining general web user behavior data for improving document ranking and other web search experience. The context of web user activities reveals their preferences and intents, and we emphasize the analysis of individual user sessions for creating aggregate models. We introduce a novel algorithm for estimating web page and web site importance, and discuss its theoretical foundation based on an intentional surfer model. We demonstrate that our approach significantly improves large-scale document retrieval performance

    Digital Image Access & Retrieval

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    The 33th Annual Clinic on Library Applications of Data Processing, held at the University of Illinois at Urbana-Champaign in March of 1996, addressed the theme of "Digital Image Access & Retrieval." The papers from this conference cover a wide range of topics concerning digital imaging technology for visual resource collections. Papers covered three general areas: (1) systems, planning, and implementation; (2) automatic and semi-automatic indexing; and (3) preservation with the bulk of the conference focusing on indexing and retrieval.published or submitted for publicatio
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