This book is a collection of the best papers originally presented as state-of-the-art reports or tutorials at the Eurographics '91 conference in Vienna. A choice has been made giving priority to timeless information. Another goal was to cover all aspects of computer graphics - except hardware - as completely as possible from modelling to advanced visualization and communication. The ten contributions by internationally renowned experts fulfil this goal perfectly. Some important problem areas treated from different viewpoints thus enhancing and deepening the reader's perspective.

The area of computer graphics is characterized by rapid evolution. New techniques in hardware and software developments, e. g. , new rendering methods, have led to new ap plications and broader acceptance of graphics in fields such as scientific visualization, multi-media applications, computer aided design, and virtual reality systems. The evolving functionality and the growing complexity of graphics algorithms and sys tems make it more difficult for the application programmer to take full advantage of these systems. Conventional programming methods are no longer suited to manage the increasing complexity, so new programming paradigms and system architectures are re quired. One important step in this direction is the introduction and use of object-oriented methods. Intuition teils us that visible graphical entities are objects, and experience has indeed shown that object-oriented software techniques are quite useful for graphics. The expressiveness of object-oriented languages compared to pure procedurallanguages gives the graphics application programmer much better support when transforming his mental intentions into computer code. Moreover, object-oriented software development is a, weil founded technology, allowing software to be built from reusable and extensible compo nents. This book contains selected, reviewed and thoroughly revised vers ions of papers submit ted to and presented at the Fourth Eurographies Workshops on Object-Oriented Graphics, held on May 9-11, 1994 in Sintra, Portugal.

The Blaubeuren Conference "Theory and Practice of Geometric Modeling" has become a meeting place for leading experts from industrial and academic research institutions, CAD system developers and experienced users to exchange new ideas and to discuss new concepts and future directions in geometric modeling. The relaxed and calm atmosphere of the Heinrich-Fabri-Institute in Blaubeuren provides the appropriate environment for profound and engaged discussions that are not equally possible on other occasions. Real problems from current industrial projects as well as theoretical issues are addressed on a high scientific level. This book is the result of the lectures and discussions during the conference which took place from October 14th to 18th, 1996. The contents is structured in 4 parts: Mathematical Tools Representations Systems Automated Assembly. The editors express their sincere appreciation to the contributing authors, and to the members of the program committee for their cooperation, the careful reviewing and their active participation that made the conference and this book a success.

Making systems easier to use implies increasingly complex management of communication between users and applications. An increasing part of the application program is devoted to the user interface. In order to manage this complexity, it is very important to have tools, notations, and methodologies that support the designer's work during the refinement process from specification to implementation. The purpose of this proceedings of the first (1994) Eurographics workshop on this area is to review the state of the art. It compares the different existing approaches in order to identify the principal requirements and the most suitable notations and methods, and indicates the relevant results.

The 14 papers in this volume vividly demonstrate the current state of research in real-time animation. Half of the papers are dedicated to algorithm allowing the real-time animation of complex articulated structure in particular (humans, legged robots, plants) and of dynamic scenes in general. The proposed approaches cover from motion capture to motion reusability which are essential issues for high-end applications as 3D games, virtual reality, etc. Other topics treated are motion management for fast design of realistic movements, 2D and 3D deformations, and various optimization techniques for simulation (adaptive mass-spring refinement, huge particule systems).

Pacific Graphics is an international conference on computer graphics and applications. The conference will provide a forum for researchers, developers, and practitioners to exchange ideas and discuss future directions of computer graphics. The past two conferences were held in Korea (1993) and China (1994), and future conferences are planned in Taiwan (1996), Korea (1997), and Singapore (1998).

In recent years, the paradigm of video coding has shifted from that of a frame-based approach to a content-based approach, particularly with the finalization of the ISO multimedia coding standard, MPEG-4. MPEG-4 is the emerging standard for the coding of multimedia content. It defines a syntax for a set of content-based functionalities, namely, content-based interactivity, compression and universal access. However, it does not specify how the video content is to be generated. To generate the video content, video has to be segmented into video objects and tracked as they transverse across the video frames. This book addresses the difficult problem of video segmentation, and the extraction and tracking of video object planes as defined in MPEG-4. It then focuses on the specific issue of face segmentation and coding as applied to videoconferencing in order to improve the quality of videoconferencing images especially in the facial region. Modal-based coding is a content-based coding technique used to code synthetic objects that have become an important part of video content. It results in extremely low bit rates because only the parameters needed to represent the modal are transmitted. Model-based coding is included to provide background information for the synthetic object coding in MPEG-4. Lastly, MPEG-4, the first coding standard for multimedia content is described in detail. The topics covered include the coding of audio objects, the coding of natural and synthetic video objects, and error resilience. Advanced Video Coding is one of the first books on content-based coding and MPEG-4 coding standard. It serves as an excellent information source and reference for both researchers and practicing engineers.