Abstract: Over the last decade, a wide spectrum of (multi­media) content has become available to an increasing number of users who desire to access it through various devices and over heterogeneous networks. Interoperability is the key for enabling transparent and augmented use of (multimedia) content across a wide range of networks and devices. Standardization efforts within the Moving Picture Experts Group (MPEG), in particular MPEG-7 and MPEG-21, aim to provide appropriate tools for achieving this goal of Universal Multimedia Access (UMA). This tutorial provides, in the first place, the concepts of UMA and corresponding MPEG-7 metadata tools built to support these concepts. Subsequently, the vision, an overview, and the state of the art of the emerging MPEG-21 Multimedia Framework are given. Finally, MPEG-21 Digital Item Adaptation (DIA) tools which implement the “Terminal and Networks Characteristics” key element within the whole framework are illustrated in detail. The goal of MPEG-21 DIA is to achieve interoperable transparent access to (distributed) advanced multimedia content by shielding users from network and terminal installation, configuration, management and implementation issues.

Abstract: XML-based metadata is widely adopted across the different communities and plenty of commercial and open source tools for processing and transforming are available on the market. However, all of these tools have one thing in common: they operate on plain text encoded metadata which may become a burden in constrained and streaming environments, i.e., when metadata needs to be processed together with multimedia content on the fly. In this paper we present an efficient approach for transforming such kind of metadata which are encoded using MPEG's Binary Format for Metadata (BiM) without additional en-/decoding overheads, i.e., within the binary domain. Therefore, we have developed an event-based push parser for BiM encoded metadata which transforms the metadata by a limited set of processing instructions – based on traditional XML transformation techniques - operating on bit patterns instead of cost-intensive string comparisons.

Abstract: XML-based metadata is widely adopted across the different communities and plenty of commercial and open source tools for processing and transforming are available on the market. However, all of these tools have the same requirement: they operate on plain text encoded metadata which may become a burden especially in constrained and streaming environments, e.g., when metadata needs to be processed together with multimedia content which is available in a highly efficient, binary representation format. In this paper we present techniques for transforming such kind of metadata which is encoded using the well known MPEG-7 Systems Binary Format for Metadata (BiM) without additional en-/decoding overheads, i.e., within the binary domain. As such it enables us to process both the multimedia data as well as the metadata within its compressed domain, e.g., for metadata-driven adaptation purposes within intermediary network nodes which are becoming increasingly popular in the multimedia community as well as in the XML community.

Abstract: XML-based metadata for digital media is becoming increasingly important, as a consequence also calling for efficient encoding and compression schemes for the storage and transport of this metadata. Moreover, support for streaming the XML metadata in conjunction with the media data is highly desirable. Such support is provided, for instance, by MPEG's Binary Format for Metadata (BiM) encoding approach, which facilitates fragmenting, delivering, and accessing the metadata in so- called Access Units (AUs). In this paper, we present a quantitative evaluation of existing XML metadata compression and encoding techniques, reaching from widely used state-of-the-art data compression algorithms to sophisticated XML-aware encoding schemes. The comparison is based on compressing MPEG-21 generic Bitstream Syntax Descriptions (gBSDs) which can grow to non-negligible sizes. The main conclusion from this investigation is that in terms of pure compression efficiency on XML files, the BiM approach (exemplified by the MPEG reference software as well as a commercial version thereof) is comparable – in terms of performance – with traditional data or specific XML compression tools. However, when XML metadata have to be fragmented, compressed, and streamed in such fragments, the results indicate that the BiM approach is superior to the other schemes.

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: 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: The information revolution of the last decade has resulted in a phenomenal increase in the quantity of multimedia content available to an increasing number of different users with different preferences who access it through a plethora of devices and over heterogeneous networks. In order to address the amount of different content types, MPEG-21 Digital Item Adaptation (DIA) introduces interoperable description tools which enable coding format independent adaptation. Bandwidthefficient transport of the content to terminals with different capabilities and through a variety of access networks with various characteristics requires adaptation facilities not only on the server but also within the network. In this paper we present transport mechanisms for MPEG-21-based metadata enabling generic adaptation within the network. Three different transport mechanisms for delivering this metadata in conjunction with the corresponding multimedia content are evaluated and a payload format for the transport of this metadata is presented. Furthermore, we performed measurements which demonstrate the bandwidth benefits of our distributed adaptation approach compared to server-centric adaptation in a multicast scenario. Finally, we applied various encoding formats for the metadata which further reduces the metadata overhead.

Abstract: The growing demand for multimedia information by different types of users equipped with a large variety of devices and connecting through different kinds of networks results in an increasing amount of different multimedia formats. Research is currently concentrating on the adaptation of the contents in order to provide Universal Multimedia Access (UMA) for the content consumer. But this does not solve the problem of the content provider, who still has to signal this variety of different multimedia formats to the consumer. In this contribution, we show a way to stream any type of multimedia format based on generic hint information. This hint information is based on a generic bit stream syntax description (gBSD) which is used for format-independent content adaptation within the MPEG-21 Multimedia Framework. Ultimately, this can lead to a frame-work which allows generic streaming and generic adaptation anywhere in the network.

Abstract: In this paper, we present a prototype application that receives Digital Video Broadcast (DVB) TV streams on a PC, extracts semantic and syntactic metadata from the MPEG-2 Transport Stream (TS), maps them to MPEG-7 compliant descriptors, and packs these metadata and the associated multimedia content into standard compliant MPEG-21 Digital Items (DIs). In this form, i.e., as DIs, the DVB content can be searched and accessed by clients such as PCs and PDAs, and can be transported over IP networks. The DVB server can be used as a live source of multimedia content to demonstrate multimedia streaming (e.g., via RTP) and adaptation to diverse devices.

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 streaming systems in best effort networks have to somehow cope with dynamically changing bandwidth. Various scalable video codecs allow intra-stream adaptation by use of temporal, spatial, or quality (SNR) scalability; optimizations for finer grained scalability are available as layered coding and FGS techniques. However, if there is no scalable video stream at hand, stream switching among pre-encoded stream versions of different bitrates and qualities allows at least coarse-grained adaptation. Those different approaches compete to be the most efficient solution for adaptive video streaming. However, this paper will show that the efficacy is significantly increased by combining those approaches. As will be discussed, the combination of coarse-grained stream switching and temporal intra-stream adaptation offers better visual results and more stable client buffer behavior than the denoted approaches used separately.

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: 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: We present a possibility how to add proactive behaviour to Video-on-Demand systems. To do so we propose categorizing videos and using external information as well as observing the behaviour of our clients. We examined 23 predictor functions on artificial and real datasets using different similarity measures to compare them. Our model is quite simple; therefore some extensions are proposed at the end.

Abstract: The diversity of end-terminal and access network capabilities as well as the dynamic nature of wireless connections pose significant challenges to providers of multimedia streaming services. In this paper, we present a system based on MPEG-21 Digital Item Adaptation (DIA) technologies that automatically adapts scalable multimedia resources, like upcoming MPEG-21 Scalable Video Coding (SVC) streams, in a generic and transparent way to the user and session context. This context includes terminal and network capabilities as well as user characteristics. A server side adaptation engine reacts to context changes by dynamic decision taking and accordingly modified bitstream adaptation. Furthermore, novel concepts are presented that facilitate multimedia adaptation in a distributed fashion along the delivery path.

Abstract: In multimedia applications, XML is being increasingly used to represent metadata; examples are MPEG-7 multimedia description schemes and MPEG-21 usage environment descriptions. As with the media data, the size of, or the overhead induced by, the XML metadata is important, particularly when used on constrained mobile devices. Therefore, compression (binary encoding) of the XML data becomes relevant to reduce this overhead. Within the MPEG-7 standardization effort, a Binary Format for Metadata (BiM) was developed, ´providing good compression efficiency and facilitating random access into, and manipulation of, the binary encoded bit stream. However, using binary encoded XML should not introduce interoperability issues with existing applications, nor add additional complexity to new applications. In this paper we investigate a solution for this issue by handling the binary encoded XML data by the XML parser. As such, applications do not need to be aware of the type of encoding of the XML data. In this paper, we introduce such an XML parser and evaluate its usability in different scenarios. We measure the memory requirements and compare the processing speed of parsing binary encoded XML to plain text XML.

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: Digital Item Adaptation (DIA) ist der jüngste Standard im Rahmen des ISO/IEC MPEG-21 Multimedia Frameworks. Dieser Standard spezifiziert Deskriptoren und Konzepte (Tools) für die interoperable Kommunikation und ggf. Adaption von komplexen digitalen multimedialen Objekten, sog. Digital Items. Schwierigkeiten der Kommunikation und ggf. die Notwendigkeit der Adaption multimedialer Inhalte entstehen durch die Heterogenität und Beschränkungen der durchlaufenen Netzwerke (z.B. im heutigen Internet) und der benutzten Endgeräte sowie durch unterschiedliche Präferenzen und Profile der Nutzer. Dieser Artikel beschreibt eine endgeräte- und codierformat-unabhängige Komponente zur Adaption von Digital Items an verschiedene mobile Endgeräte und Netzcharakteristika.

Abstract: Video adaptation is an active research area aiming at delivering heterogeneous content to yet heterogeneous devices under different network conditions. This paper presents an architecture for generating variations (different versions) from methods such as video transcoding, media conversion and summarization. The work in this paper concentrates on video data and aims to show video variation supported with metadata as an approach to adaptation to enable ubiquitous access. By video products are defined and the variation factory is introduced It generates different versions of the source and an MPEG-7 metadata document. The information contained in the metadata document helps the system to identify the most appropriate version that meets the required quality of service (QoS). In addition to the implementation of the commonly used reduction methods, two novel methods, viz. object-based and segment-based variations are introduced. Our proposals are implemented and experimentally validated.

Abstract: The rapid evolution in the hardware sector brought up various (mobile) end user devices like PDAs or cell phones on which online multimedia content can be consumed. Due to different capabilities of these devices as well as individual user preferences, the original multimedia resources have to be adapted in order to fit the specific devices’ constraints and to meet the users’ requirements. Given the high variety of possible adaptation operations both on the format as well as the content level, an intelligent multimedia server must be able to integrate multiple existing and specialized adaptation tools. In this paper, we demonstrate how the usage of modular software components and declarative descriptions of component behavior enables us to develop extensible multimedia adaptation systems. The precise semantics of the utilized functionality description mechanism as well as the defined vocabulary from existing and emerging multimedia standards also allows us to automatically assemble adaptation chains that are executed on a given resource involving multiple, externally provided software components.

Abstract: This paper introduces the principal approach and describes the basic architecture and current implementation of the knowledge-based multimedia adaptation framework we are currently developing. The framework can be used in Universal Multimedia Access scenarios, where multimedia content has to be adapted to specific usage environment parameters (network and client device capabilities, user preferences). Using knowledge-based techniques (state-space planning), the framework automatically computes an adaptation plan, i.e., a sequence of media conversion operations, to transform the multimedia resources to meet the client's requirements or constraints. The system takes as input standards-compliant descriptions of the content (using MPEG-7 metadata) and of the target usage environment (using MPEG-21 Digital Item Adaptation metadata) to derive start and goal states for the planning process, respectively. Furthermore, declarative descriptions of the conversion operations (such as available via software library functions) enable existing adaptation algorithms to be invoked without requiring programming effort. A running example in the paper illustrates the descriptors and techniques employed by the knowledge-based media adaptation system.

Abstract: Modern video streaming servers should adapt, and switch quality levels of, the streamed data according to precise and timely feedback about the network conditions, and should also incorporate selective retransmissions of important reference frames (I- and P-VOPs). This paper evaluates two recent IETF Internet Drafts on RTP extensions for immediate feedback and retransmission and shows, in conjunction with temporal video adaptation, how a substantial visual quality gain can be achieved by using those extensions (up to 4.4 dB PSNR under lossy conditions).