During the last decade, multimedia has emerged as a major research and de velopment area. Pushed by advanced technology like huge-capacity storage de vices, fast networks, and powerful work stations, new applications have arisen. Many definitions of multimedia systems exist, one of them being computer sys tems that support interactive use of at least one of the following information sources: graphics, image, voice, sound, and video. These systems have caused a boom in the world of entertainment, but also in other business areas great opportunities for novel products and services are available. The size of multi media data is often huge, and the storage of huge amounts of data is a task normally allocated to database management systems. Although some modern database management systems offer facilities to support development of multi media applications, many problems related to multimedia support are still not well understood. This book reports on research efforts to solve some of these problems. An in troductory knowledge of databases, and also of operating systems and network technology is assumed. The book is very suitable as material for courses at senior or graduate level, but also for upgrading the skills of computer scientists working on database management systems, multimedia systems or applications. The book consists of four parts. Part I is called "Requirements for a Mul timedia Database" and comprises chapters one to three. Chapter one presents an outline of the book.

InhaltsangabeI: Requirements for a Multimedia Database.- 1 Introduction.- 1.1 Introduction.- 1.2 Multimedia.- 1.3 Some Characteristics.- 1.3.1 Content-Based Retrieval.- 1.3.2 Quality of Service.- 1.3.3 Synchronisation.- 1.4 Architecture.- 1.5 Contents.- 1.5.1 Part I: Requirements for a Multimedia Database.- 1.5.2 Part II: Client Components.- 1.5.3 Part III: Server Components.- 1.5.4 Part IV: Environment.- 2 Current and Emerging Applications.- 2.1 A Multimedia Publication Environment.- 2.2 Multimedia and Database System Support for Systems Engineering.- 2.3 A Multimedia Calendar of Event Teleservice.- 2.4 The QBIC System.- 2.5 Multimedia Document Archives.- 2.6 The Informedia Project.- 2.7 Some Virtual World Applications.- 2.8 Other Emerging Applications.- 3 Multimedia and its Impact on Database System Architectures.- 3.1 Introduction.- 3.2 Characteristics.- 3.2.1 Types of Multimedia Data.- 3.2.2 Temporal Aspects.- 3.2.3 Media Representation.- 3.2.4 Data Volume.- 3.2.5 Data Modelling.- 3.2.6 Resources.- 3.2.7 User Interaction.- 3.2.8 Querying Multimedia Information.- 3.2.9 Typical Database Management Functionality.- 3.3 Building Blocks for Multimedia Database Systems.- 3.3.1 The Notion of Multimedia Database Management Systems.- 3.3.2 Multimedia Data Models.- 3.3.3 Exploiting Traditional Database System Technology.- 3.3.4 A Reference Architecture for Multimedia Database Systems.- 3.4 Conclusions.- II: Client Components.- 4 User Interaction in a Virtual World Environment.- 4.1 Introduction.- 4.2 Characteristics.- 4.2.1 Terminology.- 4.2.2 Basic Architecture.- 4.2.3 Model Representation.- 4.3 Virtual Environment Building Blocks.- 4.3.1 Effectors.- 4.3.2 Software.- 4.3.3 Interface Aspects.- 4.4 Virtual Worlds and Databases.- 4.4.1 General Characteristics of Virtual World Databases.- 4.4.2 Very Large Virtual Environments.- 4.5 Conclusions.- 5 Searching Distributed Hypermedia.- 5.1 Introduction.- 5.2 Background Information.- 5.2.1 Internet.- 5.2.2 Hypertext and Hypermedia.- 5.2.3 WWW.- 5.3 Searching and Browsing.- 5.4 Requirements for Search Support.- 5.4.1 Harvest.- 5.4.2 Semantics.- 5.4.3 Our Use of Harvest.- 5.5 Locating Publication Servers.- 5.5.1 Membership-Based Locating.- 5.5.2 Publication-Based Locating.- 5.5.3 Subscription-Based Locating.- 5.6 Searching.- 5.7 Browsing.- 5.8 Architectural Issues.- 5.8.1 Search Client.- 5.8.2 Publication Server.- 5.8.3 Disseminators.- 5.8.4 Index Facilities.- 5.8.5 Query Processing.- 5.8.6 Reducing Network Traffic.- 5.9 Conclusions.- III: Server Components.- 6 The SQL3 Server Interface.- 6.1 Introduction.- 6.2 SQL3: An Overview.- 6.2.1 Functions and Procedures.- 6.2.2 SQL3 Type System.- 6.2.3 Binary Large Objects (BLOBs).- 6.2.4 Other Facilities.- 6.3 Assessment of SQL3 Facilities.- 6.3.1 SQL3 as an Implementation Vehicle.- 6.3.2 SQL3-Based Type Definitions for MM Objects.- 6.3.3 Limitations of SQL3.- 6.4 Summary.- 7 The SGML/HyTime Server Interface.- 7.1 Introduction.- 7.2 SGML.- 7.3 HyTime.- 7.4 Case Study.- 7.4.1 The Case.- 7.4.2 Examples of HyTime Documents.- 7.5 Application in Practice.- 8 Content-Based Querying.- 8.1 Introduction.- 8.2 Multimedia Object Modelling and Similarity-Based Querying.- 8.2.1 Multimedia Description Model.- 8.2.2 Multimedia Interpretation Model.- 8.3 Content-Based Retrieval in Text Document Database Systems.- 8.3.1 Similarity Measures for Text Retrieval.- 8.3.2 Query Expansion Using Concept Relationships.- 8.4 Content-Based Querying in Image Database Systems.- 8.4.1 Image Similarity Based on Global Image Features.- 8.4.2 Image Similarity Based on Image Subobject Features.- 8.5 Searching in Video Database Systems.- 8.5.1 Automatic Shot Detection.- 8.5.2 Video Information Modeling and Querying.- 8.6 Conclusions.- 9 Query Processing.- 9.1 Introduction.- 9.2 Access and Storage.- 9.2.1 Multimedia Storage Techniques.- 9.2.2 Multimedia Access Methods.- 9.3 Dimensions in Multimedia Query Processing.- 9.3.1 Query Predicates.- 9.3.2 Active and Passive Components.- 9.3.3 Exact Match/Pa