Browsing NUP Academic Publications - Ακαδημαϊκές Δημοσιεύσεις ΠΝΠ by Author "Zagoris, Konstantinos"

Now showing items 1-15 of 15

  • Accurate Image Retrieval Based on Compact Composite Descriptors and Relevance Feedback Information 

    Chatzichristofis, Savvas A.; Zagoris, Konstantinos; Boutalis, Yiannis S.; Papamarkos, Nikos (World Scientific Publishing Company, 2010)
    In this paper a new set of descriptors appropriate for image indexing and retrieval is proposed. The proposed descriptors address the tremendously increased need for e±cient content-based image retrieval (CBIR) in many ...

  • Automatic Image Annotation and Retrieval Using the Joint Composite Descriptor 

    Zagoris, Konstantinos; Chatzichristofis, Savvas A.; Papamarkos, Nikos; Boutalis, Yiannis (Institute of Electrical and Electronics Engineers (IEEE), United States, 2010)
    Capable tools are needed in order to successfully search and retrieve a suitable image from large image collections. Many content-based image retrieval systems employ low-level image features such as color, texture and ...

  • Bag-of-visual-words vs global image descriptors on two-stage multimodal retrieval 

    Zagoris, Konstantinos; Chatzichristofis, Savvas A.; Arampatzis, Avi (ACM SIGIR 2011, 2011)
    The Bag-Of-Visual-Words (BOVW) paradigm is fast becoming a popular image representation for Content-Based Image Retrieval (CBIR), mainly because of its better retrieval effectiveness over global feature representations ...

  • Comparative Performance Evaluation of Image Descriptors Over IEEE 802.11b NoisyWireless Networks 

    Chatzistavros, Evaggelos; Chatzichristofis, Savvas A.; Stamatellos, Georgios; Zagoris, Konstantinos (IEEE (Computer Society), 2011)
    Abstract—In this paper we evaluate the image retrieval procedure over an IEEE 802.11b Ad Hoc network, operating in 2.4GHz, using IEEE Distributed Coordination Function CSMA/CA as the multiple access scheme. IEEE 802.11 ...

  • DUTH at ImageCLEF 2011 Wikipedia Retrieval 

    Arampatzis, Avi; Zagoris, Konstantinos; Chatzichristofis, Savvas A. (ImageClef, Wikipedia Retrieval Task, 2011)
    As digital information is increasingly becoming multimodal, the days of single-language text-only retrieval are numbered. Take as an example Wikipedia where a single topic may be covered in several languages and include ...

  • Dynamic two-stage image retrieval from large multimedia databases 

    Arampatzis, Avi; Zagoris, Konstantinos; Chatzichristofis, Savvas A. (Elsevier, 2013)
    Content-based image retrieval (CBIR) with global features is notoriously noisy, especially for image queries with low percentages of relevant images in a collection. Moreover, CBIR typically ranks the whole collection, ...

  • Dynamic Two-Stage Image Retrieval from Large Multimodal Databases 

    Arampatzis, Avi; Zagoris, Konstantinos; Chatzichristofis, Savvas A. (Springer-Verlag, 2011)
    Content-based image retrieval (CBIR) with global features is notoriously noisy, especially for image queries with low percentages of relevant images in a collection. Moreover, CBIR typically ranks the whole collection, ...

  • Fusion vs. Two-Stage for Multimodal Retrieval 

    Arampatzis, Avi; Zagoris, Konstantinos; Chatzichristofis, Savvas A. (Springer, 2011)
    We compare two methods for retrieval from multimodal collections. The first is a score-based fusion of results, retrieved visually and textually. The second is a two-stage method that visually re-ranks the top-K results ...

  • A Fuzzy Rank-Based Late Fusion Method for Image Retrieval 

    Chatzichristofis, Savvas A.; Zagoris, Konstantinos; Boutalis, Yiannis; Arampatzis, Avi (Springer-Verlag, 2012)
    Rank-based fusion is indispensable in multiple search setups in lack of item retrieval scores, such as in meta-search with non-cooperative engines. We introduce a novel, simple, and efficient method for rank-based late ...

  • img(Anaktisi): A Web Content Based Image Retrieval System 

    Zagoris, Konstantinos; Chatzichristofis, Savvas A. (IEEE, 2009)
    img(Anaktisi) is a C#/.NET content base image retrieval application suitable for the web. It provides efficient retrieval services for various image databases using as a query a sample image, an image sketched by the ...

  • Multimedia Search with Noisy Modalities: Fusion and Multistage Retrieval 

    Arampatzis, Avi; Chatzichristofis, Savvas A.; Zagoris, Konstantinos (ImageClef, Wikipedia Retrieval Task, 2010)
    We report our experiences from participating to the controlled experiment of the ImageCLEF 2010 Wikipedia Retrieval task. We built an experimental search engine which combines multilingual and multi-image search, employing ...

  • Text localization using standard deviation analysis of structure elements and support vector machines 

    Zagoris, Konstantinos; Chatzichristofis, Savvas A.; Papamarkos, Nikos (Springer, 2011)
    A text localization technique is required to successfully exploit document images such as technical articles and letters. The proposed method detects and extracts text areas from document images. Initially a connected ...

  • The TREC files: the (ground) truth is out there 

    Chatzichristofis, Savvas A.; Zagoris, Konstantinos; Arampatzis, Avi (Association for Computing Machinery (ACM), United States, 2011)
    Traditional tools for information retrieval (IR) evaluation, such as TREC’s trec_eval, have outdated command-line interfaces with many unused features, or ‘switches’, accumulated over the years. They are usually seen ...

  • TsoKaDo: An Image Search Engine Performing Recursive Query Recommendation Based on Visual Information 

    Tsochatzidis, Lazaros T.; Kapoutsis, Athanasios Ch.; Dourvas, Nikos I.; Chatzichristofis, Savvas A.; Boutalis, Yiannis; Zagoris, Konstantinos (IARIA, 2012)
    This paper tackles the problem of the user’s incapability to describe exactly the image that he seeks by introducing an innovative image search engine called TsoKaDo. Until now the traditional web image search was based ...

  • www.MMRetrieval.net: a multimodal search engine 

    Zagoris, Konstantinos; Chatzichristofis, Savvas A.; Arampatzis, Avi (Association for Computing Machinery (ACM), United States, 2010)
    We introduce an experimental search engine for multilin- gual and multimedia information, employing a holistic web interface and enabling the use of highly distributed indices. Modalities are searched in parallel, and ...