Multimedia Copyright Protection

Internet and its widespread usage for multimedia document distribution put the copyright issue in a complete new setting. Multimedia documents, specifically those installed on a web page, are no longer passive as they typically include active applets. Copyright protection safeguards the intellectual property (IP) of multimedia documents, which are either sold or distributed free of charge. In this Chapter, the basic tools for copyright protection are discussed. First, general concepts and the vocabulary used in copyright protection of multimedia documents are discussed. Later, taxonomy of watermarking and fingerprinting techniques are studied. This part is concluded by a review of the literature dealing with IP security. The main part of the chapter discusses the generic watermarking scheme and illustrates it on three specific examples: collusion-free watermarking, spread spectrum watermarking, and software fingerprinting. Future trends and conclusions close the chapter.

Review of Fuzzy Image Segmentation Techniques

This chapter provides a comprehensive overview of various methods of fuzzy logic-based image segmentation techniques. Fuzzy image segmentation techniques outperform conventional techniques, as they are able to evaluate imprecise data as well as being more robust in noisy environment. Fuzzy clustering methods need to set the number of clusters prior to segmentation and are sensitive to the initialization of cluster centers. Fuzzy rule-based segmentation techniques can incorporate the domain expert knowledge and manipulate numerical as well as linguistic data. It is also capable of drawing partial inference using fuzzy IF-THEN rules. It has been also intensively applied in medical imaging. These rules are, however, application-domain specific and very difficult to define either manually or automatically that can complete the segmentation alone. Fuzzy geometry and thresholding-based image segmentation techniques are suitable only for bimodal images and can be applied in multimodal images, but they don’t produce a good result for the images that contain a significant amount of overlapping pixels between background and foreground regions. A few techniques on image segmentation based on fuzzy integral and soft computing techniques have been published and appear to offer considerable promise.

Virtual Sets

Techniques of filming using special effects have existed since the 1920s, well before the advent of computers. Two of them are known as Back Projection—when an actor acts in front of a screen that reproduces other footage (very common in train scenes), and Blue Screen—when an actor acts in front of a blue wall for later composition with another scene (Fielding, 1985). However, it was computer graphics and the technological advance of the computers that made possible the great evolution in this area. Virtual Sets or Virtual Studios are denominations given to the integrated use of computer-generated elements with real actors and objects in a studio. Its main advantages are: more flexibility in changing the scene, risky scenes can be made safely, allowing the production of complex special effects and also providing economy in the production of sophisticated designs, along with flexibility in making quick changes. With the advent of high-speed networks, there is the possibility of remote operation. Real-time Virtual Sets is a very recent area for computer graphics with potential applications in the film and television industry. The literature about this topic is scarce although there are few commercial systems available, which will be described later. This work approaches Virtual Sets, describing its conceptualization and showing its correlation with other areas in computer graphics. The Virtual Sets’ pertinent technologies are identified in computer graphics and have their given solutions and unsolved problems argued.

A Framework for Supporting Reuse in Hypermedia

This chapter presents a conceptual framework which supports reuse in hypermedia applications. Reuse is important in hypermedia, and especially hypervideo, as it is rich in content but often costly to capture, store and annotate. The framework’s use is illustrated through three different example hypervideo applications which exhibit several forms of reuse. This chapter goes beyond the notion of reuse of parts of hypermedia applications and considers the reuse of classes of structure of hypermedia applications, and the issues relating to such reuse. Future systems can be developed which utilise this approach to modeling video content as illustrated in Bryan-Kinns (1998; 2000). The key contribution of this chapter is the illustration of a novel approach to modeling video, rather than how this could be implemented as discussed in other chapters.

A Semiotic Model of Multimedia

Models of multimedia communication are attempts to classify the numerous types of media objects available, and to provide a basis for the use of unambiguous terminology in a new and expanding field. Many of these models are products of theory, rather then practical investigation, and few have been empirically studied to assess their suitability. This chapter firstly presents a novel multimedia model (called TOMUS) which is based on a common classification of semiotic representational systems, and uses three dimensions of sign, syntax and modality. By separating the classification of the nature of the text to be communicated from the nature of the technology or interaction, the model provides a focussed terminology for consistent and appropriate discussion about multimedia texts. The chapter also reports on an experiment which investigated the understandability of the dimensions comprising TOMUS. The experiment entailed subjects classifying various media objects according to the TOMUS model. Error and perceived difficulty data were collected; analysis of this data revealed which of the categories are the most difficult to comprehend. Suggestions are made as to the causes of these difficulties, and recommendations as to how the model might be correspondingly altered are proposed.

Using Animation to Enhance 3D User Interfaces for Multimedia

Cartoon animation techniques have previously been used to enhance the illusion of direct manipulation in 2D graphical user interfaces. In particular, animation may be used to convey a feeling of substance to the objects being manipulated by the user. To lay a solid framework for this work, an extensive review of current applications of animation to user interfaces is presented. This chapter goes on to present an expansion of the 2D animation concepts to the domain of 3D interfaces for multimedia and virtual reality. This chapter focuses on the improvement of the legibility of users’ actions in 3D multimedia and virtual reality applications, and details animation effects to support this legibility. In particular, I present animation effects for 3D graphical object manipulation. These effects include a standard set of 3D direct manipulation operations which have been extended to include animated visual feedback to add substance, operation cues for the user and constraint visualisation. The visual feedback effects using 3D warping can substitute for haptic feedback, as in the case of the squashing of an object when pressed against a wall, or the stretching of an object to show frictional forces. Finally, a pinning effect is explored for multiple users’ manipulating a common object in a collaborative environment.

Semantic Content-Based Retrieval for Video Documents

The advancement of multimedia technologies has enabled electronic processing of information to be recorded in formats that are different from the standard text format. These include image, audio and video formats. The video format is a rich and expressive form of media used in many areas of our everyday life, such as in education, medicine and engineering. The expressiveness of video documents is the main reason for their domination in future information systems. Therefore, effective and efficient access to video information that supports video-based applications has become a critical research area. This has led to the development of, for example, new digitizing and compression tools and technology, video data models and query languages, video data management systems and video analyzers. With applications of a vast amount of stored video data, such as news archives and digital television, video retrieval became, and still is, an active area of research.

Design and Evaluation of a Content-Based Image Retrieval System

The growth in size and accessibility of multimedia databases has changed our approach to information retrieval. Classical text-based systems show their limitations in the context of multimedia retrieval. In this chapter, we address the problem of conceiving and evaluating a content-based image retrieval system. First, we investigate the use of the query-by-example (QBE) paradigm as a base paradigm for the development of a content-based image retrieval system (CBIRS). We show that it should be considered as a complement to the classical textual-based paradigms. We then evaluate the capabilities of the most up-to-date computer vision techniques in contributing to the realisation of such a system. Further, beyond the necessity of accurate image understanding techniques, we show that the amount of the data involved in the process of describing image content should also be considered as an important issue. This aspect of our study is largely based on the experience acquired by the text retrieval (TR) community, which we adapt to the context of CBIR. Similarly, the text retrieval community has also developed significant experience in evaluating retrieval systems, where judgements include subjectivity and context dependency. Extending this experience, we study a coherent framework for performing the evaluation of a CBIRS. As a practical example, we user our Viper CBIR system, using a novel communication protocol called MRML (Multimedia Retrieval Markup Language) to pinpoint the importance of the sharing of resources in facilitating the evaluation and therefore the development of CBIRS.

Fuzzy Query Languages for Multimedia Data

This chapter presents a fuzzy-based algebra, called SAMEW, to query multimedia objects. SAMEW 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 SAMEW 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 SAMEW. Optimization issues are also briefly discussed.

HTSPN

Multimedia authoring involves people not familiar with formal design techniques, but eager to check documents against synchronization, scheduling and resource allocation errors. Visual modeling with Petri Nets answers that need with a graphic syntax and a formal semantics that makes models executable. A Petri Net defines a bipartite graph where summits are divided into places associated with data processing functions and transitions which represent synchronization points. The chapter discusses an experiment with Hierarchical Time Stream Petri Nets, a timed extension of Petri Nets which was designed with distributed multimedia systems in mind. HTSPNs define a unified framework to structure complex and interactive documents. Dynamic synchronization strategies based on temporal intervals composition make it possible to take the asynchronous nature of distributed systems into account. Last but not least, a HTSPN remains an open model, which can be extended with implementation details regarding, e.g., the URLs and the presentation characteristics. The interpreted model or I-HTSPN for short, has been instantiated for MHEG and Java, respectively. The MHEG I-HTSPN editor, document checker and code generator were prototyped in C++ for Solaris. The Java I-HTSPN counterpart has been developed in Java. Their use is exemplified on a guided tour of a university and a distance learning application.