Multimedia Data

With the increasing ubiquity of sensors and computational resources, it is becoming easier and increasingly common for people to electronically record, photographs, text, audio, and video gathered over their lifetime. Assimilating and taking advantage of such data requires recognition of its multimedia nature, development of data models that can represent semantics across different media, representation of complex relationships in the data (such as spatio-temporal, causal, or evolutionary), and finally, development of paradigms to mediate user-media interactions. There is currently a paucity of theoretical frameworks and implementations that allow management of diverse and rich multimedia data collections in context of the aforementioned requirements. This paper presents our research in designing an experiential Multimedia Electronic Chronicle system that addresses many of these issues in the concrete context of personal multimedia information. Central to our approach is the characterization and organization of media using the concept of an "event" for unified modeling and indexing. The event-based unified multimedia model underlies the experiential user interface, which supports direct interactions with the data within a unified presentation-exploration-query environment. In this environment, explicit facilities to model space and time aid in exploration and querying as well as in representation and reasoning with dynamic relationships in the data. Experimental and comparative studies demonstrate the promise of this research.

We present a novel approach for estimating mesh saliency. Our method is fast, flexible, and easy to implement. By applying the well-known concept of Shannon entropy to 3D mesh data, we obtain an efficient method to determine mesh saliency. Comparing our method to the most recent, state-of-the-art approach, we show that results of at least similar quality can be achieved within a fraction of the original computation time. We present saliency-guided mesh simplification as a possible application.

Mobile Ad Hoc Networks (MANET) have emerged as one of the most significant areas of research in the field of mobile computing. However, the dynamics of mobile, wireless ad hoc networks as a consequence of mobility and disconnection of mobile hosts pose a number of problems in designing proper routing schemes for effective communication between any source and destination. The protocols proposed so far in this context and mechanisms for data communication have failed to ensure a stable QoS in such an infrastructure primarily due to two main reasons. First, due to the dynamism of the ad hoc architecture, uninterrupted multimedia (or any other data) communication has to rely heavily on the changing link stability. And, second, on link failures, resuming communication requires the entire route-establishment process to be redone. This generates intolerable overhead and delay. In this paper, we address the problem of maintaining a stable route in a resource limited, dynamic architecture li...

Collaborative filtering requires a centralized rating database. However, within a peer-to-peer network such a centralized database is not readily available. In this paper, we propose a fully distributed collaborative filtering method that is self-organizing and operates in a distributed way. Similarity ranks between multimedia files (items) are calculated by log-based user profiles and are stored locally at these items in so-called buddy tables. This intuitively creates a semantic overlay to organize multimedia files. Based on this semantic overlay and the items that a user has downloaded previously (indicating the profile of the user), recommendations can be performed and the recommended items can be easily located. We have tested our distributed collaborative filtering approach and compared it to centralized collaborative filtering, showing that it has similar performance. It is therefore a promising technique to facilitate filtering for relevant multimedia data in P2P networks.

To my parents for providing endless energy. To my brothers for giving me an opportunity to study overseas. Multimedia plays an important role in current information society since multimedia efficiently represent perceptional data. Textual data, audio, images, and video are integrally called multimedia. Image is one of the most popular mediums. An image is a two dimensional signal stored as an array of pixels and symbolises visual information. " One image is worth thousand words" would be a sentence describing the information reflecting image meaning. It is clear that how to describe image meaning completely is difficult. This directly testifies that images effectively convey information rather than text. Moreover, many constituent complex sentences can be represented by an image. For example, novel computer operating systems such as windows 98 prefer to use graphical user interface such as icons instead of complicated commands. In addition, the use of images makes the deprivafion of descripfion problems to appear. For instance, advertising designers can visually demonstration their goods to prospective customers in order to query and generate orders. The problem of how to access and manage non-textual information is progressively apparent as expressed by the nature of image data, the storage requirements, the image representations, and the rapid growth of the use of image data. In this thesis, image INTRODUCTION meaning is obscure, and the access of image is problematic. Therefore, it is clear that the techniques achieve a high degree of compression, regardless of the information management perspective. Finally, users rapidly migrate from textual data services to multimedia services. This stems from two main reasons. Firstly, multimedia presentation perceptually conveys information. This makes an efficient communication process, and most information is comprehensive. This forms the new medium for information interchange. Secondly, a global network for information interchange is available. The Internet is the biggest network connecting the world. The Internet services such as world-wide-web encourage interchange of information among users. This is more so when users have easily understandable data stream like multimedia. Furthermore, the running cost of the Internet services is affordable for personal use. As indicated by the natural mean of multimedia, content-based retrieval of multimedia data is more appropriate. Supporting this heuristic, MPEG-7 standard aims to address this issue. From the information management perspective, retrieval of small data sets from a large collection of data streams is a central idea. Tremendous data streams are a significant impediment for retrieval. Fortunately, existing compression techniques obtain a high degree of compression. However, again, the techniques only support efficiency of storage and transmission management. They are developed based on representation models. The models include, (i) pixel intensities, (ii) pixels grouping to vectors, (iii) two dimensional grouping of pixels into regions occupying stationarity, and (iv) two dimensional grouping into region of pixels retaining high level semantic scheme such as object. Content-based choice of features. For instance, sub-string matching [67] is appropriate for keywords. The success of any feature set in measuring similarity depends more or less on the use of an appropriate metric. From the literature, existing image databases are specific to applications and are not supportive to content-based retrieval. Image retrieval in most of the systems is equivalent to content-based retrieval systems. Moreover, design criteria for retrieval systems are highlighted. Finally, a retrieval model is proposed for further experiments. Chapter 3 presents three image features that will be used for retrieval and discusses their characteristics. As similarity measures, the image metrics corresponding to the features are also briefly described. Recent studies indicate that content-based retrieval is more appropriate for multimedia data streams. From these studies, the solutions are not completely provided. Content-based retrieval relates to at least three aspects, namely the retrieval, database, and data representation aspects. This thesis aims to address the retrieval aspect. Conceptual issues of content-based retrieval are studied. An image model that is persuasive to content-based retrieval is proposed. From the retrieval point of view, the thesis nominates three features, namely the Zemike moments, the Fourier descriptors, and the wavelet descriptors. The features are extracted

Much working time is spent in meetings and, as a consequence, meetings have become the subject of multidisciplinary research. Virtual Meeting Rooms (VMRs) are 3D virtual replicas of meeting rooms, where various modalities such as speech, gaze, distance, gestures and facial expressions can be controlled. This allows VMRs to be used to improve remote meeting participation, to visualize multimedia data and as an instrument for research into social interaction in meetings. This paper describes how these three uses can be realized in a VMR. We describe the process from observation through annotation to simulation and a model that describes the relations between the annotated features of verbal and non-verbal conversational behavior. As an example of social perception research in the VMR, we describe an experiment to assess human observers' accuracy for head orientation.

Scalable multimedia data transmission are subject to specific constraints such as the Quality of Service (QoS) of sensitivity classes and the transmission rate (yielding a maximum size of each frame to send). Many scalable source decoders are used to discarding data than processing an erroneous stream. This featuring class structure is helpful to define a strategy that determines the maximum number of classes to send and delivers the suitable protection and transmission scheme (coding rates and modulation) to apply in accordance with the transmission constraints. It leads to the possible truncation of frame parts transmitted with an Unequal Error Protection (UEP) scheme for severe channel conditions. In a MPEG-4 speech frames context, we compare our approach to other methods using equal error and existing UEP schemes. It results in a significant improvement of the Peak SNR (PSNR) quality in poor channel transmission conditions.

The first SBC Challenge aims to provide solutions to the problem of managing large volumes of multimedia data. Our goal is to contribute towards research in these directions by discussing the problems involved in sharing scientific digital information. First, we propose a conceptual framework (SciFrame) that helps to understand the main issues involved and to integrate related research efforts. Second, we use a real case study to point out problems which are particular to scientific data management. Finally, we describe our case study using SciFrame. Resumo. O primeiro Grande Desafio da SBC está voltado a soluc ¸ões para o problema do gerenciamento de grandes volumes de dados multimídia. Nosso objetivo é contribuir para a pesquisa nessa direc ¸ão através da discussão do compartilhamento de dados científicos em mídia digital. Primeiro, propomos um arcabouc ¸o conceitual (SciFrame) que ajuda o entendimento dos principais problemas envolvidos e integra esforc ¸os de pesquisa relacionados. Segundo, utilizamos um estudo de caso real para destacar problemas particulares ao contexto de gerenciamento de dados científicos. Finalmente, exploramos alguns problemas presentes no estudo de caso, organizando-os através do arcabouc ¸o proposto.

A prototype multimedia medical database is described for supporting thermal ablation therapy of brain tumors. Its design is motivated by the major need to manage and access multimedia information on the progress and reaction of tumors to various therapy protocols. The database links images to patient data in a way that permits the user to view and query medical information using alphanumeric, temporal, and feature-based predicates. Visualization programs permit the user to view or annotate the query results in various ways. ~[hese results support the wide variety of data types and presentation methods required by neuroradiologists to manage thermal ablation therapy data. The database satisfactorily meets the requirements defined by thermal ablation therapy. A similar approach is being undertaken for supporting different therapies of other tvPes of tumors, thus showing the generality of our approach.

This research work studies the performance of the internet services of institution of higher learning in Nigeria. Data was collated from Lagos State University of Science and Technology (LASUSTECH) as case study of this research work. The problem of Internet Bandwidth optimization in the institution of higher learning in Nigeria was extensively addressed in this paper. The operation of the Link-Load balancer which provides an efficient costeffective and easy-to-use solution to maximize utilization and availability of Internet access is discussed. In this research work, the Lagrange's method of interpolation was used to predict effective internet data bandwidth for significantly increasing number of internet users. The linear Lagrange's interpolation model (LILAGRINT model) was proposed for LASUSTECH. The predictions allow us to view the effective internet data bandwidth with respect to the corresponding acceptable number of internet users as the number of user's increases. The integrity of the model was examined, verified and validated at the ICT department of the institution. The LILAGRINT model was integrated into the management of ICT and tested. The result showed that the proposed LILAGRINT model proved to be highly effective and innovative in the area of internet data bandwidth predictability.

This paper presents some recent developments at DISTInfoMus Lab on multimodal and cross-modal processing of multimedia data streams with a particular focus on interactive systems exploiting Tangible Acoustic Interfaces (TAIs). In our research multimodal and cross-modal algorithms are employed for enhancing the extraction and analysis of the expressive information conveyed by gesture in non-verbal interaction. The paper discusses some concrete examples of such algorithms focusing on the analysis of high-level features from expressive gestures of subjects interacting with TAIs. The features for explicit support of multimodal and cross-modal processing in the new EyesWeb 4 open platform (available at www.eyesweb.org) are also introduced. Results are exploited in a series of public events in which the developed techniques are applied and evaluated with experiments involving both experts and the general audience. Research is carried out in the framework of the EU-IST STREP Project TAI-CH...

With continued increase in the use of smartphones, user expectations of content access have also increased. Most of the content that exists today is not designed for mobile devices. Mobile devices cannot directly access most of the content due to the mismatch in device capability and content playback requirements. Content adaptation is an essential tool that bridges the gap between device capabilities and content formats. In this paper we present an overview of content adaptation and survey recent papers on content adaptation for mobile devices. We introduce the when, where, and what of content adaptation to help classify the content adaptation techniques and to select the appropriate techniques for a given content delivery environment.

This technological era is raising new challenges towards the storage and management of data, that is getting more complex and imprecise with the evolution of utilization of computer engineering in most of the areas of society. To confront the arising challenges, database researchers has introduced fuzzy object oriented databases, by blending the concepts of database management system, object oriented data modeling and fuzzy techniques. This paper approaches to define and standardize the conceptual modeling for the fuzzy object oriented databases and recognize the scope of their application in the fields of science, engineering, agriculture, spatial, astronomical, environmental and medical sciences.

This chapter presents a fuzzy-based algebra, called SAME W , to query multimedia objects. SAME W allows for dealing within a common framework with several aspects relevant to similarity query processing as well as with the inherent imprecision that characterizes data, user requests, and query results. Non-Boolean, namely fuzzy and similarity, predicates are used to rank tuples according to specific criteria. Complex multi-predicate queries can be formed by means of logical connectives, whose semantics is parameterized in order to adapt to specific scenarios. The same holds for the semantics of algebraic operators. These include properly extended traditional relational operators and new operators which allow threshold and best-matches queries to be easily expressed. A further important feature of SAME W is the possibility of weighting both predicates and operands of algebraic operators so as to better fit user preferences/requirements. A working example dealing with Web data is used throughout the chapter to show the potentialities of SAME W . Optimization issues are also briefly discussed.

Future Internet applications are expected to have higher QoS requirements. Therefore, routing protocols must be adapted to find a path which satisfies such requirements. Most multicast applications are QoS sensitive in nature, because they involve the transmission of real-time multimedia data streams. There are several research projects aiming to extend existing multicast routing protocols with QoS capabilities, or even proposing new QoS aware ones. However key requirements for inter-domain routing like scalability, intra-domain independence, and policy awareness are missing in most of existing multicast routing protocols. In this paper, it is proposed an inter-domain multicast routing strategy that builds inter-domain unidirectional multicast distribution trees, taking into account multicast specific routing policies, and supporting QoS requirements.

Substantial progress has been made recently in finding acoustic features that describe perceptually relevant aspects of sound. This paper presents a general framework for synthesizing audio manifesting arbitrary sets of quantifiable acoustic features of the sort used in music information retrieval and other sound analysis applications. The methods described have broad applications to the synthesis of novel musical timbres, processing by analysisresynthesis, efficient audio coding, generation of psychoacoustic stimuli, and music information retrieval research.

We present a general framework for synthesizing audio manifesting arbitrary sets of perceptually motivated, quantifiable acoustic features. Much work has been done recently on finding acoustic features that describe perceptually relevant aspects of sound. The ability to synthesize sounds defined by arbitrary feature values would allow perception researchers to more directly generate stimuli "to order," as well as providing an opportunity to directly test the perceptual relevance and characteristics of such features. The methods we describe also provide a straightforward way of approaching the problem of mapping from data to synthesis control parameters for sonification.

Community clouds are formed when a cloud infrastructure is created to support the needs of multiple, independent service consumers that have shared concerns. Such infrastructures may allow member organizations to share resources on an opportunistic basis, i.e., one entity may provide services to the other members during off-peak times, and may in turn consume services from other members. Thus each member provides permanent or transient services according to their competencies and excess. This paper sets forth a conceptual architecture, examines the opportunities offered by such systems, and initiates a conversation on the business implications. Community-commerce brokering expands the choices for business from "where can I buy/use a service" to "whom do I want to sell my excess services to".

The huge size of multimedia data requires for efficient data classification and organization in providing effective multimedia data manipulation. Those valuable data must be captured and stored for potential purposes. One of the main problems in Multimedia Information System (MIS) is the management of multimedia data. As a consequence, multimedia data management has emerged as an important research area for querying, retrieving, inserting and updating of these vast multimedia data. This research considers the rough set theory technique to organize and categorize the multimedia data. Rough set theory method is useful for exploring multimedia data and simplicity to construct multimedia data classification. Classification will help to improve the performance of multimedia data retrieving and organizing process.

We study the joint source channel coding problem of transmitting an analog source over a Gaussian channel in two cases -(i) the presence of interference known only to the transmitter and (ii) in the presence of side information known only to the receiver. We introduce hybrid digital analog forms of the Costa and Wyner-Ziv coding schemes. Our schemes are based on random coding arguments and are different from the nested lattice schemes by Kochman and Zamir that use dithered quantization. We also discuss superimposed digital and analog schemes for the above problems which show that there are infinitely many schemes for achieving the optimal distortion for these problems. This provides an extension of the schemes by Bross et al to the interference/side information case. We then discuss applications of the hybrid digital analog schemes for transmitting under a channel signal-to-noise ratio mismatch and for broadcasting a Gaussian source with bandwidth compression. v 1+ P σ 2 . This optimal performance can be achieved by two very simple schemes. The first one is separate source and channel coding, where the source is first quantized and the quantization index is transmitted using an optimal code for the AWGN channel. The second scheme is uncoded (analog) transmission with power scaling , where the source is not explicitly quantized. Recently, it was shown by Bross, Lapidoth and Tinguely [6] that there is a family of infinitely many schemes that are optimal, which contains the separation based scheme and uncoded (analog) transmission as special cases.

The paper presents an overview of research related to the problem of the data warehouse (DW) evolution. Related research can usually be grouped into three approaches -schema evolution, schema versioning and view maintenance. The main contributions of the paper are: a) DW evolution state of the art, and b) critical analysis of existing methods and approaches to the DW schema evolution. Also, general idea and direction for our future work is briefly described.

In order to improve security, the project focuses on chaotic map-driven image encryption, which uses Arnold's Cat Map in conjunction with the 2D Sine Map to create confusion and pixel scrambling. While Arnold's Cat Map offers a non-linear distortion that further jumbles the image pixels to fortify encryption, the 2D Sine Map, which is notorious for its chaotic character, produces random values that are essential for the first transformation. To provide strong data protection, the encryption algorithm SEME-TDHM (Secure Enhanced Modified Encryption-Time-Dependent Hybrid Mapping) integrates both of these chaotic maps in a timedependent way. Multiple rounds of transformations and substitutions are incorporated into the SEME-TDHM algorithm to guarantee a high level of complexity, which strengthens the encryption against a variety of assaults. The image's security is further increased by the combination of chaotic maps and the SEME-TDHM algorithm, which guarantees that the encrypted output is extremely difficult to decipher without the right keys, providing a cutting-edge method for secure image transmission.

This paper discusses standards-based approaches for secure data sharing across organizations. In particular, current standards as well as standardization trends for data integration, multimedia data management, active real-time data management, data warehousing and mining, expert data management, semantic web data management, knowledge management, visualization, metadata extraction and management, and security management for data sharing are discussed. We will illustrate the ideas with an example from emergency response and public health awareness application domain.

There has been much recent progress in building ontologies and publishing scientific data based on these ontologies. This paper overviews issues and progress in the other half of semantic science: having machine accessible scientific theories that can make predictions on this data and can be used for new cases. This paper presents the grand vision, issues that have arisen in building such systems for the geological domain (minerals exploration and geo-hazards), and sketches the formal foundations that underlie this vision.

Existing search engines use web crawlers to gather web pages. The extracted information is used to build indexes, which are later used to answer user queries. This approach is useful for general queries, but ignores the special properties of sound files, making it difficult to accurately locate specific sound files on the web. AROOOGA, or the Articulated Resource for Obsequious Opinionated Observations into Gathered Audio, is a web crawling system designed specifically to find and analyze audio resources on the web. The AROOOGA web crawler uses both audio information and the associated web pages to produce higher-quality search indexes for music information retrieval. Information about sound files on the web is discussed, and some preliminary search results are included.

This paper describes the improvement of web cache server by scoping in replacement algorithm of data which are collected from the clients. We have found that each replacement algorithm is suitable for each type of data in the web pages. Therefore, we introduce the mechanism to select the replacement algorithm depending on the size of data called the Replacement Algorithm Selection Mechanism (RASM). RASM allows the web cache server to have the suitable replacement algorithm for each type of data. As the result, the byte hit ratio of web cache server can be increased and the congestion in the network can be alleviated.

During the process of information hiding in a cover image, LSB-based steganographic techniques like JSteg change the statistical properties of the cover image. Accordingly, such information hiding techniques are vulnerable to statistical attack. The understanding of steganalysis methods and their effects can help in designing methods and algorithms preserving data privacy. In this paper, we compare some steganalysis methods for attacking LSB-based steganographic techniques (logistic regression, the tree-based ...

outside of the research work he is also a great mentor, from whom I learn a lot about important things in life. For the time he made available for research discussions, the effort he spent on reading and revising my research papers and thesis, the help he offered when I was in trouble, and the patience he showed against my late progress, I am always thankful. I would also like to thank my replacement supervisor, Asst. Prof. Ken Sung Wing Kin, for allowing me to stay in his laboratory and for assisting me with all the administrative matters. I am sincerely grateful for his tremendous effort to help my research keep on as smoothly as possible. This study would not have been possible without the Research Scholarship I received from the National University of Singapore. Therefore, I thank the Universityand the School of Computing, in particular -for giving me the opportunity to pursue my postgraduate study. iii Through my many years in Multimedia Information Laboratory, I had worked with not just colleagues but caring and hospitable friends. I have benefited from many research discussions with Hongguang, William, Junli, Li Xiang, Su Mu, and Choon Keng as much as I have enjoyed their warm and sincere friendship. My interaction with other friends like Meng, Rain Zhang, Akanksha, Wenjie, and Xiao Yan has made my stay there pleasant and lively. Moreover, I am indebted to my brothers and sisters in Christ for their support, prayers, and companionship. In particular, I would like to thank -among others -Eni and Martin, Henny and Karim, Evelyne and Didi, Aini, and my Cell Group's and Prayer Group's friends. I thank Heng Thong, my flatmate, for the same support, prayers, and companionship he has given me. An abundance of appreciation and gratitude also goes to Dina, who kept "jia you"-ing me all the way till the completion of this thesis. I really hope one day I can repay you the same favor. Above all, I would like to express my highest appreciation to my parents, sister, and brother for their endless love, compassion, encouragement, and persistent prayers. Forever, I owe them an immense debt of gratitude. To them, I dedicate this thesis.

The television industry has undergone a massive transformation with the rise of Internet Protocol Television (IPTV). Unlike traditional cable and satellite TV, IPTV leverages the internet to deliver content, offering flexibility, interactivity, and enhanced viewing experiences. This paper explores the working mechanism of IPTV, its technological foundations, and its potential future in the rapidly evolving digital landscape

The modern expansion of public streaming has played a considerable part in the growth of distributed multime- dia, with special reference to video. However, since the Internet is an inter-connected web of different network speeds, streaming video is still a difficult service to implement to all locations. This paper illustrates two simple simulated network streaming environments. The first models a broadcast network and the second model represents a multicast network. A simple cache system is then implemented into these models to investigate whether a significant difference exists between the cache size and the different network bandwidths of these two optimization systems. This caching system will then be used to compare the impact of videos (characterised by different resolutions and degrees of picture motion) on the cache performance. Index Terms—Network simulation, Cache, Multicasting, Video streaming, NS-2, Distributed Multimedia, Evalvid, I. INTRODUCTION Distributed media stre...

This paper presents a system that provides access to a newspaper web site. The system is based on an interaction model, that uses browse and search strategies, and on an information model, which is made up of a tree and indexes. A frame-based approach is used to control the dialog flow. VoiceXML is used as a language to describe dialog turns. The systems works for Spanish language. To measure the usability of the system we evaluated the performance using objective measures and user satisfaction using SASSI questionnaire. The results of the evaluation show a task success rate of 92% and a WER of 18.09%. Overall user satisfaction is positive: users perceive the system as useful and easy to use. We conclude the paper with a discussion of the most relevant issues about the development and evaluation of the system.

Recommender systems help people in retrieving information that match their preferences by recommending products or services from a large number of candidates, and support people in making decisions in various contexts: what items to buy , which movie to watch or even who they can invite to their social network . They are especially useful in environments characterized by a vast amount of information, since they can e↵ectively select a small subset of items that appear to fit the user's needs. We present the main points related to recommender systems using multimedia data, especially for social networks applications. We also describe, as an example, a framework developed at the University of Naples "Federico II". It provides customized recommendations by originally combining intrinsic features of multimedia objects (low-level and semantic similarity), past behavior of individual users and overall behavior of the entire community of users, and eventually considering users' preferences and social interests.

techniques develop, various applications are increasing including multi-user social networking and education applications that involve talking avatars. Due to a lack of sensory information for full face and body motion capture in consumer-grade VR, most VR applications do not show a synced talking face and body. We propose a novel method, targeted for VR applications, for talking face synced with audio with an upper-body inverse kinematics. Our system presents a mirrored avatar of a user himself in single-user applications. We implement the mirroring in a single user environment and by visualizing a synced conversational partner in multi-user environment. We found that a realistic talking face avatar is more influential than an un-synced talking avatar or an invisible avatar.

As a fundamental theorem in number theory, the Chinese Reminder Theorem (CRT) is widely used to construct cryptographic primitives. This paper investigates the security of a class of image encryption schemes based on CRT, referred to as CECRT. Making use of some properties of CRT, the equivalent secret key of CECRT can be recovered efficiently. The required number of pairs of chosen plaintext and the corresponding ciphertext is only (1 + (log 2 L)/l ). The attack complexity is only O(L), where L is the plaintext length and l is the number of bits representing a plaintext symbol. In addition, other defects of CECRT such as invalid compression function and low sensitivity to plaintext, are reported. The work in this paper will help clarify positive role of CRT in cryptology.

We are developing a next generation multimedia server that provides fully interactive access to tremendous amounts and varieties of real-time and non real-time multimedia data by hundreds of simultaneous clients. Current multimedia servers are inadequate for this task given their support of only basic multimedia data types, inherently non-interactive access semantics and/or intrinsic scaling limitations. Our solution abandons the common use of striping and object replication, and implements a random data allocation scheme across a cluster of commodity computers. This scheme provides implicit load balancing both within and among storage nodes of the cluster while supporting virtually any multimedia data type and application access pattern. This paper presents the essential background, design and implementation, and simulation studies of the storage server component of our system. Our results show that we can guarantee with high probability that an arbitrary I/O requests can be satisfied within a small delay bound while obtaining high system utilization. Although our specific application is a real-time multimedia storage server, techniques developed here can be applied to scalability in distributed systems in general.

The insufficiency of labeled training data for representing the distribution of the entire dataset is a major obstacle in automatic semantic annotation of large-scale video database. Semi-supervised learning algorithms along with adaptive techniques, attempt to learn from both labeled and unlabeled data, are promising to solve this problem. In this paper, retrieving videos using key words requires obtaining the semantic features of the videos. Most work reported in the literature focuses on different key frame extraction techniques and shot detection methods along with annotating a video shot with a fixed number of key words, no matter how much information is contained in the video shot.Two level keyframe extraction is performed for removal of redundant keyframes.The aim is to find minimal of Keyframes.

In order to achieve true content-based information retrieval on video we should analyse and index video with high-level semantic concepts in addition to using user-generated tags and structured metadata like title, date, etc. However the range of such high-level semantic concepts, detected either manually or automatically, is usually limited compared to the richness of information content in video and the potential vocabulary of available concepts for indexing. Even though there is work to improve the performance of individual concept classifiers, we should strive to make the best use of whatever partial sets of semantic concept occurrences are available to us. We describe in this paper our method for using association rule mining to automatically enrich the representation of video content through a set of semantic concepts based on concept co-occurrence patterns. We describe our experiments on the TRECVid 2005 video corpus annotated with the 449 concepts of the LSCOM ontology. The evaluation of our results shows the usefulness of our approach.

The SHREC'10 Shape Retrieval Contest of Range Scans aims at comparing algorithms that match a range scan to complete 3D models in a target database. The queries are range scans of real objects, and the objective is to retrieve complete 3D models that are of the same class. This problem is essential to current and future vision systems that perform shape based matching and classification of the objects in the environment. Two groups have participated in the contest. They have provided rank lists for the query set, which is composed of 120 range scans of 40 objects.

W E take great pleasure in introducing this special section on ªQuality of Service Issues in Internet Web Servicesº to the readership of the IEEE Transactions on Computers. This special section is comprised of seven papers, spanning caching, prefetching, replication, admission control, and router scheduling. The topics covered include theoretical and implementation aspects of provisioning quality of service (QoS). A large fraction of Internet users access network resources through web clients/browsers. The quality of service (QoS) experienced by their Internet users has gained great importance in recent years. Furthermore, new web applications require the delivery of multimedia data in real time (e.g., streaming stored video and audio) and information transfer through the Internet is becoming one of the principal paradigms for business: electronic sales, banking, finance, collaborative work are a few examples of this. The QoS perceived by its users is thus becoming a dominant factor for the success of an Internet-based Web service. The principal QoS attributes users perceive include those related to the service ªresponsiveness,º i.e., the service availability and timeliness. The performance perceived by the users of a web service depends on the protocols that operate between web clients and servers. Solutions currently investigated in the literature range from new protocols to enhance the network QoS (e.g., differentiated services) to mechanisms running into the end systems to enhance the QoS perceived by the users (e.g., caching, prefetching, Web servers' replications, etc.). In the medium-term, it is envisaged that the Internet will evolve to a universal transport service that will be able to provide on demand delivery of multimedia data with QoS guarantees. Currently, the best effort service provided by an IP network has necessitated development of middleware tools to overcome insufficient bandwidth and high latency. The issues that need to be addressed to improve the QoS are:

Results: The selection process for this yearbook’s section “Sensor, signal and imaging informatics ” results in six excellent articles, representing research in five different nations. We selected a cross section of the wide range of application, ranging from model based image segmentation, image retrieval and data mining, image based diagnosis assistance, bio-impedance based skin cancer screening, brain computer interfaces to MRI based computational models for fluid-structure-interactions. Conclusions: The selected articles indicate a small but meaningful extract from the research field of sensors, signal and image processing, which has a wide range of applications in medical informatics. The articles present excellent research with a possibility of having high relevance for the future in patient care.

Real-time video encryption is a critical need in today's digital era. With the proliferation of online activities like streaming, virtual meetings, and transmission of sensitive data, the demand for secure data transmission is at an all-time high. In this paper, a new algorithm is proposed for encrypting MPEG-4 video frames. This algorithm involves encrypting the DCT values of a macroblock XOR-ed with the encryption key to significantly enhance the encryption speed and robust security while reducing the computational cost.

Internet is migrating from a simple data network to an environment where a more demanding multimedia content like audio, video, and IP telephony is being delivered. The Internet Protocol (IP) was originally designed to interconnect heterogeneous networks. It scales well by keeping the core network as simple and dumb as possible and provides a best effort delivery service. However, multimedia

Due to the rapid growth of the number of digital media elements like image, video, audio, graphics on Internet, there is an increasing demand for effective search and retrieval techniques. Recently, many search engines have made image search as an option like Google, AlltheWeb, AltaVista, Freenet. In addition to this, Ditto, Picsearch, can search only the images on Internet. There are also other domain specific search engines available for graphics and clip art, audio, video, educational images, artwork, stock photos, science and nature [www.faganfinder.com/img]. These entire search engines are directory based. They crawls the entire Internet and index all the images in certain categories. They do not display the images in any particular order with respect to the time and context. With the availability of MPEG-7, a standard for describing multimedia content, it is now possible to store the images with its metadata in a structured format. This helps in searching and retrieving the images. The MPEG-7 standard uses XML to describe the content of multimedia information objects. These objects will have metadata information in the form of MPEG-7 or any other similar format associated with them. It can be used in different ways to search the objects. In this paper we propose a system, which can do content based image retrieval on the World Wide Web. It displays the result in user-defined order.

Current approaches to content-based retrieval of multimedia data usually rely either on query by example or on sketches of the desired image, but not on both. In this paper, we propose a new query specification scheme, where digital images are combined with sketches, after vectorization, taking advantage of both methods. We selected a set of algorithms to perform image vectorization, taking into account the trade-off between vector image quality and processing time. This method of specifying queries is part of a system to retrieve vector drawings, which we briefly describe in this paper.

Many indexing approaches for high-dimensional data points have evolved into very complex and hard to code algorithms. Sometimes this complexity is not matched by increase in performance. Motivated by these ideas, we take a step back and look at simpler approaches to indexing multimedia data. In this paper we propose a simple, (not simplistic) yet efficient indexing structure for high-dimensional data points of variable dimension, using dimension reduction. Our approach maps multidimensional points to a 1D line by computing their Euclidean Norm. In a second step we sort these using a B +-Tree on which we perform all subsequent operations. We exploit B +-Tree efficient indexed sequential search to develop simple, yet performant methods to implement point, range and nearest-neighbor queries. To evaluate our technique we conducted a set of experiments, using both synthetic and real data. We analyze creation, insertion and query times as a function of data set size and dimension. Results so far show that our simple scheme outperforms current approaches, such as the Pyramid Technique, the A-Tree and the SR-Tree, for many data distributions. Moreover, our approach seems to scale better both with growing dimensionality and data set size, while exhibiting low insertion and search times.