Abstract: The ISO/IEC Motion Picture Group (MPEG) issued in 2002 a standard, called MPEG-7, which enables the content description of multimedia data in XML. The standard supports applications to exchange, identify and filter multimedia contents based on MPEG-7 descriptions. However, especially mobile applications that deal with MPEG-7 suffer from limited bandwidth, low computational power and limited battery life. In this document we describe an index system that allows filter mechanisms and random access to encoded MPEG-7 streams and which overcome the limitation of the network and the consuming terminal. Encoding is applied in order to reduce the data rate of the XML documents to be transmitted. The indexed parts of the encoded streams can be accessed without the need to deserialize the complete stream. Furthermore, the system is evaluated and results of the experimental evaluation are discussed.

Abstract: Extracting and visualizing concepts and relationship between text documents strongly depends on the used similarity measure. In order to provide meaningful visualizations and to extract useful knowledge from document collections, user needs must be captured by the internal representation of documents, and the used similarity measure. In most applications the Vector Space Model and the Cosine similarity are used therefore and serve as good approximations. Nevertheless, influencing similarities between documents is rather hard, since parameter tuning relies heavily on expert knowledge of the underlying algorithms, and the influence of different weighting schemes and similarity measures is not known before. In this paper we present an approach on how to adapt the vector space representation of documents by giving visual feedback to the system. Our approach starts by clustering a corpus of text documents and visualizing the results using multi dimensional scaling techniques. Afterwards, a 2D landscape visualization is shown which can be manipulated by the user. Based on these manipulations the high dimensional representation of the documents is adapted to fit the users need more precisely. Our experiments show that iterating these steps results in an adapted representation of documents and similarities, generating layouts as intended by the user and furthermore increases clustering accuracy. While this paper only investigates the influence on clustering and visualization, the method itself may also be used for increasing classification and retrieval performance since it adapts to the users need of similarity.

Abstract: The increasing diversity of devices and the heterogeneity of networks pose nowadays a challenge in the delivery and consumption of multimedia content. In this context, the Part 7 of the MPEG-21 standard formally named Digital Item Adaptation (DIA) targets the adaptation of multimedia content based on usage environment, such as network characteristics, terminal capabilities and user characteristics. But, MPEG-21 DIA does not take into account MPEG-7 semantics description tools, which provide means for a conceptual (semantic) description that is close to the human understanding of multimedia content. Therefore, to fill this gap, we propose an interactive and user-centric framework called Semantic Adaptation Framework (SAF). The SAF provides facilities for the generation of all the required semantic metadata and enables an MPEG-21 adaptation engine to semantically adapt the multimedia content in order to provide the user with the best possible experience.

Abstract: The DAHL project aimed at demonstrating some of the research achievements at ITEC by extending anexisting web application with content-based search mechanisms and an adaptive streaming environment for video data. The search is based on MPEG-7 descriptions of video data, and video retrieval uses an MPEG-4 conforming adaptive streaming server and player, which allows to adapt the video stream dynamically to client capabilities, user preferences, and available network bandwidth. This report describes the design, implementation, and integration work done in the DAHL project.

Abstract: We argue for the need of a tool that is able to provide QoS aware server applications with accurate information about current as well as predicted network characteristics. To address this issue, we present the design and evaluation of DANEF - a system that is able to estimate, process and forecast bottleneck bandwidth, available bandwidth, delay, jitter and loss of a certain path. Active measurements are performed by sending small ICMP packet trains and forecasts are performed by applying fast allgorithms that need only small initialization sets. The accuracy of the measurements is achieved by applying an efficient and innovative filtering mechanism, the correctness of the forecasts is achieved by dynamically selecting the best fitting forecast model and by considering the forecast error of previous samples. Our evaluation has shown that DANEF's measurement results are significantly more precise than those yield by the 5 most widely used tools called Bprobe, Cprobe, Pathload, Pathchar and Network Weather Service.

Abstract: We present the extension of an adaptive distributed multimedia streaming server architecture (ADMS) towards a Quality of Service based network infrastructure. The key component of the extension is the distributed active network estimation and forecasting tool (DANEF). It is able to estimate, process and forecast bottleneck bandwidth, available bandwidth, delay, jitter and loss of a certain path between the streaming server and the requesting client. Using this information, the server node that offers the best QoS for a certain client is selected from a set of possible candidates. Active measurements are performed by sending ICMP [15] packet trains and forecasts are performed by applying fast algorithms that need only small initialization sets. The accuracy of the measurements is achieved by applying an efficient and innovative filtering mechanism, the correctness of the forecasts is achieved by dynamically selecting the best fitting forecast model and by considering the forecast error of previous samples. We have compared DANEF to other already existing measurement tools like BProbe, Cprobe, Pathload, Pathchar and Network Weather Service. As can be found in the evaluation part of this paper DANEF is much better suited for estimating QoS characteristics in the context of multimedia streaming than the other 5 tools it has been compared to.

Abstract: In recent years there has been a big increase in the amount and usage of all different kinds of multimedia data. Ranging from digital video broadcasting over the Internet to sharing digital photos and videos from the last holidays with others, multimedia is around everywhere today. Multimedia metadata help us to manage and search for information in these data. They offer searching for keywords as well as semantic search for textual descriptions of complex activities in audio, video and image. Based upon the research and implementation of the DAHL project, we present an approach for the annotation and presentation of content-variations of videos. First we want to have a look at muvino, a tool for creating MPEG-7 metadata descriptions of videos. After that the presentation of search results, especially the variations of videos or video segments is highlighted

Abstract: Video adaptation is an active research area aiming at delivering heterogeneous content to yet heterogeneous devices under different network conditions. It is an important component of multimedia data management to address the problem of delivering multimedia data in distributed heterogeneous environments. This paper presents a novel method of video adaptation called segment-based adaptation. It aims at applying different reduction methods on different segments based on physical content. The video is first partitioned into homogeneous segments based on physical characteristics. Then optimal reduction methods are selected and applied on each segment with the objective of minimizing quality loss and/or maximizing data size reduction during adaptation. In addition to this new method of variation creation, the commonly used reduction methods are also implemented. To realize variation creation, a unifying framework called the Variation Factory is developed. It is extended to the Multi-Step Variation Factory, which allows intermediary videos to serve as variations and also as sources to further variations. Our proposals are implemented as part of a server component, called the Variation Processing Unit (VaPU) that generates different versions of the source and an MPEG-7 metadata document.

Abstract: Unser Tutorial gibt einen Überblick über die neuesten MPEG-Standards MPEG-7/21/A/B und streicht ihre Bedeutung für Multimedia-Datenbanken heraus.

Abstract: This paper introduces a new approach of approximating the selectivity of multimedia range queries. Estimating the selectivity of a range query is a pre-requisite to optimize a multimedia database query. We use the DBSCAN clustering technique for finding high density areas in the data set. Then, the selectivity is approximated with the help of a density function in combination with the volume of the query’s hypersphere. Our approach is fast and accurate which was evaluated on an image data set using the MPEG-7 Scalable Color Descriptor. The technique is integrated with the help of the extensible optimizer architecture in the Oracle multimedia database system.

Abstract: During its lifetime, multimedia content undergoes different stages or cycles fromproduction to consumption. Content is created, processed or modified in a postproduction stage, delivered to users, and finally, consumed. Metadata, or descriptive data about the multimedia content, pass through similar stages but with different time lines.1 Metadata may be produced, modified, and consumed by all actors involved in the content production-consumption chain. At each step of the chain, different kinds of metadata may be produced by highly different methods and of substantially different semantic value.

Abstract: Im MPEG-21 Multimedia Framework Standard spielt das Digital Item als fundamentale Transaktions- und Austauscheinheit eine zentrale Rolle. Dieser Artikel beschreibt eine Methodik und Software zur Erstellung und den Konsum von Digital Items. Das Softwarewerkzeug setzt sich aus zwei Teilen zusammen: Der DI Builder erlaubt es Benutzern MPEG-21 Digital Items zu erstellen, die mit dem DI Consumer konsumiert werden können. Der Konsum eines Digital Items umfasst das Abspielen von Mediendateien und die Betrachtung der Metadaten eines Digital Items. Die Software demonstriert Teile des MPEG-21 Standards, im speziellen Teil 2-Digital Item Declaration, Teil 3-Digital Item Identifcation, Teil 5-Rights Expression Language, Teil 6-Rights Data Dictionary und Teil 7-Digital Item Adaptation.

Abstract: The ISO/IEC Motion Picture Group (MPEG) issued in 2002 a standard, called MPEG-7, which enables the content description of multimedia data in XML. The standard supports applications to exchange, identify and filter multimedia contents based on MPEG-7 descriptions. However, processing MPEG-7 documents on mobile terminals is problematic, since the verbose XML is not adequate to limited bandwidth, low computational power and limited battery life. In this document we describe an index system that allows filtering and random access to encoded MPEG-7 streams and which overcomes the limitation of the network and the consuming terminal. Encoding is applied in order to reduce the data rate of the XML documents to be transmitted. The indexed parts of the encoded streams can be accessed without the need to deserialize the complete stream. Furthermore, the system is evaluated and results of the experimental evaluation are discussed.

Abstract: This paper presents the experiences of creating the information system MEDPHYT which is built to collect data on the complete European pharmaceutical and toxicological plant world whose representatives are determined by medical and therapeutic benefit. Focus of the database content is the plant with description of their botanical characteristics, and history of discovery of therapeutic use, etymology, and synonyms. Apart the botanical characterisation there is information on both medical relevant biochemical compounds and their physicochemical characteristics, and toxicological as well as pharmaceutical facts. These data sets determine the basic system of MEDPHYT.

Abstract: Universal Multimedia Access (UMA) has become a driving concept behind a significant amount of research activities. One of MPEG’s (Moving Pictures Experts Group) responses to UMA is MPEG-21 Digital Item Adaptation (DIA). In this paper we present how tools as specified within DIA (i.e., normative XML-based description formats) are applied in streaming and constrained environments enabling piece-wise multimedia content adaptation including the adaptation decision-taking process and the actual resource adaptation in a coding format-independent way. Additionally, we demonstrate how the metadata overhead imposed by DIA tools can be reduced by means of appropriate metadata encoding tools.

Abstract: The precision of the predictors used in the ADMS[1] can be determined by similarity. There are already such measures[2] given, but we do not know exactly what efficiency they have and how well they show the difference between two lists. Kendall’s tau • Spearman’s footrule • Ulam’s distance We examined the characteristics of these similarity measures and developed some more measures that fit better our needs. One of the main goals is to consider the similarity more important at the begin of list, than at the end of list. Because the clients at the begin of the list probably will request more videos. During our work we defined 20 special ordered lists with 17 elements each. We tested the different measures on these lists. We also tested the Kemeny distance, which was defined in paper[3]. We modified the Spearman’s footrule and the Ulam’s distance according to the goal defined above (the top of the list considerate with higher weight (Weighted Spearman’s footrule, Weighted Ulam’s distance). Using the already known measures we developed a more complex, mixed measure, which uses more factors when defining the similarity. Finally we compared the 7 different measures using the artificially defined lists. With using the similarity measures we can tell how good the predictors[2] work in ADMS project. We could order the predictors by goodness, testing them on a real database (the World Cup ’98 Website’s access log).

Abstract: Proxy-cache deployment in the LANs has become a current practice aimed at increasing the availability of the data while also reducing client perceived latency, reduce the load on origin servers as well as the external network bandwidth consumption. As the load increases, due to an increase in client’s requests for both cached and non-cached data, it often happens that one single proxy-cache can not handle all the incoming requests. For those situations, when request dropping and cache replacement becomes necessary, we propose an alternative, namely proxy-cache splitting. Our solution is to dynamically deploy additional proxy-caches inside the LAN, and divert towards them some of the requests addressed to the original proxy-cache(s). By doing this we can achieve even better response time, load balancing, higher availability and robustness of the service than in the case in which a single proxy-cache is used.

Abstract: The importance of the historical and human aspects of the didactics of informatics is discussed. The threefold human aspects of teaching: by, for and about people is explored. Using the example of the notion of the procedure, the potential of the historical discussion is investigated. A strengthening of the historical and human view is required both in university research and in the curricula of the informatics education at both secondary and university levels.

Abstract: We argue for the need of a tool that is able to provide QoS aware server applications with accurate information about current as well as predicted network characteristics. To address this issue, we present the design and evaluation of DANEF - a system that is able to estimate, process and forecast bottleneck bandwidth, available bandwidth, delay, jitter and loss of a certain path. Active measurements are performed by sending small ICMP packet trains and forecasts are performed by applying fast allgorithms that need only small initialization sets. The accuracy of the measurements is achieved by applying an efficient and innovative filtering mechanism, the correctness of the forecasts is achieved by dynamically selecting the best fitting forecast model and by considering the forecast error of previous samples. Our evaluation has shown that DANEF's measurement results are significantly more precise than those yield by the 5 most widely used tools called Bprobe, Cprobe, Pathload, Pathchar and Network Weather Service.

Abstract: We argue for the need of a tool that is able to provide QoS aware server applications with accurate information about current as well as predicted network characteristics. To address this issue, we present the design and evaluation of DANEF - a system that is able to estimate, process and forecast bottleneck bandwidth, available bandwidth, delay, jitter and loss of a certain path. Active measurements are performed by sending small ICMP packet trains and forecasts are performed by applying fast allgorithms that need only small initialization sets. The accuracy of the measurements is achieved by applying an efficient and innovative filtering mechanism, the correctness of the forecasts is achieved by dynamically selecting the best fitting forecast model and by considering the forecast error of previous samples. Our evaluation has shown that DANEF's measurement results are significantly more precise than those yield by the 5 most widely used tools called Bprobe, Cprobe, Pathload, Pathchar and Network Weather Service.