School of Information Sciences: Recent submissions

Now showing items 121-140 of 163

  • Accelerating Image Retrieval Using Binary Haar Wavelet Transform on the Color and Edge Directivity Descriptor 

    Chatzichristofis, Savvas A.; Boutalis, Yiannis; Arampatzis, Avi (Institute of Electrical and Electronics Engineers (IEEE), United States, 2010)
    In this paper, a new accelerating technique for content-based image retrieval is proposed, suitable for the Color and Edge Directivity Descriptor (CEDD). To date, the experimental results presented in the literature ...

  • 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 ...

  • Content based MRSI image indexing and retrieval involving a fuzzy descriptor 

    Chatzichristofis, Savvas A.; Boutalis, Yiannis; Karras, D. A.; Mertzios, B. G. (Institute of Electrical and Electronics Engineers (IEEE), United States, 2010)
    Magnetic resonance spectroscopic imaging (MRSI) integrates both spectroscopic and imaging methods to produce spatially localized spectra from within the sample or patient. Although MRSI is a relatively new imaging technology ...

  • Late fusion of compact composite descriptors for retrieval from heterogeneous image databases 

    Chatzichristofis, Savvas A.; Arampatzis, Avi (Association for Computing Machinery (ACM), United States, 2010)
    Compact composite descriptors (CCDs) are global image features, capturing more than one types of information at the same time in a very compact representation. Their quality has so far been evaluated in retrieval from ...

  • Performance Study of the Most Commonly Used Image Retrieval Evaluation Methods 

    Chatzichristofis, Savvas A.; Boutalis, Yiannis (ACTA PRESS, 2010)
    One of the most significant problems in the field of image retrieval results from the lack of a common test bed for the evaluation of the systems. So far, many of the methods used in the field of information retrieval ...

  • SPCD - SPATIAL COLOR DISTRIBUTION DESCRIPTOR - A Fuzzy Rule based Compact Composite Descriptor Appropriate for Hand Drawn Color Sketches Retrieval 

    Chatzichristofis, Savvas A.; Boutalis, Yiannis; Lux, Mathias (SCITEPRESS, 2010)
    In this paper, a new low level feature suitable for Hand Drawn Color Sketches retrieval is presented. The proposed feature structure combines color and spatial color distribution information. The combination of these two ...

  • 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 ...

  • Automatic summarization and annotation of videos with lack of metadata information 

    Papadopoulos, Dim P.; Kalogeiton, Vicky S.; Chatzichristofis, Savvas A.; Papamarkos, Nikos (Elsevier, 2013)
    The advances in computer and network infrastructure together with the fast evolution of multimedia data has resulted in the growth of attention to the digital video’s development. The scientific community has increased the ...

  • A Multi-Objective Exploration Strategy for Mobile Robots Under Operational Constraints 

    Amanatiadis, Angelos A.; Chatzichristofis, Savvas A.; Charalampous, Konstantinos; Doitsidis, Lefteris; Kosmatopoulos, Elias B.; Tsalides, Phillipos; Gasterato, Antonios; Roumeliotis, Stergios I. (IEEE, 2013)
    Multi-objective robot exploration constitutes one of the most challenging tasks for autonomous robots performing in various operations and different environments. However, the optimal exploration path depends heavily on ...

  • Content-based image retrieval over IEEE 802.11b noisy wireless networks 

    Chatzistavros, Evaggelos; Chatzichristofis, Savvas A.; Zagoris, Konstatinos; Stamatelos, George (Wiley, 2014)
    Mobile devices such as smartphones and tablets are widely used in everyday life to perform a variety of operations, such as e-mail exchange, connection to social media, bank/financial transactions, and so on. Moreover, ...

  • Img(Rummager): An Interactive Content Based Image Retrieval System 

    Chatzichristofis, Savvas A.; Boutalis, Yiannis; Lux, Mathias (IEEE (Institute of Electrical and Electronics Engineers , United States), 2009)
    This paper presents an image retrieval suite called img(Rummager) which brings into effect a number of new as well as state of the art descriptors. The application can execute an image search based on a query image, either ...

  • Selection of the Proper Compact Composite Descriptor for Improving Content based Image Retrieval 

    Chatzichristofis, Savvas A.; Boutalis, Yiannis; Lux, Mathias (ACTA Press, Canada, 2009)
    Compact Composite Descriptors (CCD) are global image features capturing both, color and texture characteristics, at the same time in a very compact representation. In this paper we propose a combination of two recently ...

  • Image Encryption using the Recursive Attributes of the eXclusive-OR Filter 

    Chatzichristofis, Savvas A.; Marques, Oge; Lux, Mathias; Boutalis, Yiannis (Springer, 2014)
    This paper describes a visual multimedia content encryption approach based on cellular automata (CA), expanding the work proposed in [4]. The presented algorithm relies on an attribute of the eXclusive-OR (XOR) filter, ...

  • Vision-Controlled Micro Flying Robots: From System Design to Autonomous Navigation and Mapping in GPS-Denied Environments 

    Scaramuzza, Davide; Achtelik, Michael; Doitsidis, Lefteris; Fraundorfer, Friedrich; Kosmatopoulos, Elias; Martinelli, Agostino; Achtelik, Markus Wilhelm; Chli, Margarita; Chatzichristofis, Savvas A.; Kneip, Laurent; Gurdan, Daniel; Heng, Lionel; Lee, Gim Hee; Lynen, Simon; Meier, Lorenz; Pollefeys, Marc; Renzaglia, Alessandro; Siegwart, Roland; Stumpf, Jan Carsten; Tanskanen, Petri; Troiani, Chiara; Weiss, Stephan (IEEE, 2014)
    Autonomous micro helicopters are about to play a major role in tasks like search and rescue, environment monitoring, security surveillance, inspection, etc. If they are further realized in small scale, they can also be ...

  • How Smart Are Smartphones?: Bridging the marketing and information technology gap. 

    Amanatiadis, Angelos; Chatzichristofis, Savvas A. (IEEE, 2014)
    The term "smart" has become widespread in consumer electronics in recent years, reflecting the consumers' need for devices that assist them in their daily activities. The term has a long history of usage in marketing science ...

  • Hybrid Cellular Ants for Clustering Problems 

    Bitsakidis, Nikolaos P.; Chatzichristofis, Savvas A.; Sirakoulis, Georgios Ch. (Old City Publishing, 2014)
    In the last decade the amount of the stored data related to almost all areas of life has rapidly increased. However, the overall process of discovering knowledge from data demands more powerful clustering techniques to ...

  • Real-time indexing for large image databases: color and edge directivity descriptor on GPU 

    Bampis, Loukas; Iakovidou, Chryssanthi; Chatzichristofis, Savvas A.; Boutalis, Yiannis S.; Amanatiadis, Angelos (Springer, 2014)
    In this paper, we focus on implementing the extraction of a well-known low-level image descriptor using the multicore power provided by general-purpose graphic processing units (GPGPUs). The color and edge directivity ...

  • Image Moment Invariants as Local Features for Content Based Image Retrieval using the Bag-of-Visual-Words Model 

    Karakasis, Evangelos G.; Amanatiadis, Angelos; Gasteratos, Antonios; Chatzichristofis, Savvas A. (Elsevier, 2015)
    This paper presents an image retrieval framework that uses affine image moment invariants as descriptors of local image areas. Detailed feature vectors are generated by feeding the produced moments into a Bag-of-Visual-Words ...

  • What, Where and How? Introducing pose manifolds for industrial object manipulation 

    Kouskouridas, R.; Amanatiadis, A.; Chatzichristofis, Savvas A.; Gasteratos, A. (Elsevier, 2015)
    In this paper we propose a novel method for object grasping that aims to unify robot vision techniques for 24 efficiently accomplishing the demanding task of autonomous object manipulation. Through ontological 25 concepts, ...