MPEG-4 compatible faces from orthogonal photos
MPEG-4 is scheduled to become an international standard in March 1999. The paper demonstrates an experiment for a virtual cloning method and animation system, which is compatible with the MPEG-4 standard facial object specification. Our method uses orthogonal photos (front and side view) as input and reconstructs the 3D facial model. The method is based on extracting MPEG-4 face definition parameters (FDP) from photos, which initializes a custom face in a more capable interface, and deforming a generic model. Texture mapping is employed using an image composed of the two orthogonal images, which is done completely automatically. A reconstructed head can be animated immediately inside our animation system, which is adapted to the MPEG-4 standard specification of face animation parameters (FAP). The result is integrated into our virtual human director (VHD) system.

title: Generating Animatable 3D Virtual Humans from Photographs
abstract: We present an easy, practical and efficient full body cloningmethodology. This system utilizes photos taken from the front, side and back of a person in any given imaging envir onment without requiring a special background or a controlled illuminating condition. A seamless generic bo dy specified in the VRML H-Anim 1.1 format is used to generate an individualized virtual human. The system is c of two major components: face-cloning and body-cloning. The face-cloning component uses feature poi nts on front and side images and then applies DFFD for shape modification. Next a fully automatic seamless text ure mapping is generated for 360 o coloring on a 3D polygonal model. The body-cloning component has two step s: (i) feature points specification, which enables automatic silhouette detection in an arbitrary background(ii) two-stage body modification by using feature points and body silhouette respectively. The final integrated huma n model has photo-realistic animatable face, hands, feet and body. The result can be visualized in any VRML compli ant browser.

title: Real Face Communication in a Virtual World
abstract: This paper describes an efficient method to make an individual face for animation from several possible inputs and how to use this result for a realistic talking head communication in a virtual world. We present a method to reconstruct 3D facial model from two orthogonal pictures taken from front and side views. The method is based on extracting features from a face in a semiautomatic way and deforming a generic model. Texture mapping based on cylindrical projection is employed using a composed image from the two images. A reconstructed head is animated immediately and is able to talk with given text, which is transformed to corresponding phonemes and visemes. We also propose a system for individualized face-to-face communication through network using MPEG4.

title: Personalized face and speech communication over the Internet
abstract: We present our system for personalized face and speech communication over the Internet. The overall system consists of three parts: the cloning of real human faces to use as the representative avatars; the Networked Virtual Environment System performing the basic task of network and device management; and the speech system which includes a text-to-speech engine and a real time phoneme extraction engine from natural speech. The combination of these three elements provides a system to allow real humans, represented by their virtual counterparts, to communicate with each other even when they are geographically remote. In addition to this, all elements present use MPEG-4 as a common communication and animation standard and were designed and tested on the Windows operating system (OS). The paper presents the main aim of the work, the methodology and the resulting communication system.

title: Simulating Virtual Humans in Networked Virtual Environments
abstract: In the past decade, networked virtual environments (NVEs) have been an increasingly active area of research, with the first commercial systems emerging recently. Graphical and behavioral representation of users within such systems is a particularly important issue that has lagged in development behind other issues such as network architectures and space structuring. In this paper, we expose the importance of using virtual humans within these systems and provide a brief overview of several virtual humans technologies used in particular for simulation of crowds. As the main technical contribution, the paper presents the integration of these technologies with the COVEN-DIVE platform, the extension of the DIVE system developed within the COVEN project. In conjunction with this, we present our contributions through the COVEN project to the MPEG-4 standard concerning the representation of virtual humans.

title: Facial shape and 3D skin
abstract: We present novel ideas for facial shape and skin simulation on extremely detailed threedimensional facial meshes. Our input database is composed of a small number of scanned human faces with resolutions up to several million triangles, where even the pores are clearly distinguished. We show how to decompose the facial meshes into the global shape of the face plus skin detail (3D skin), and then to reconstitute them. Our modeling methodology allows us to simulate the exaggeration of the facial global shape, retaining the original skin detail, as well as to transfer 3D skin from one face to another. First, we represent all the input faces in terms of a homogeneous structure on the base model in low resolution by using mesh adaptation techniques. Second, the differences between the original mesh and a base mesh, which appear as skin detail, are captured and stored, so that each face is decomposed into the global shape (a base mesh) plus skin detail. Face reconstitution after global shape exaggeration and/or skin transfer enables delicate simulation of facial models. In addition, we can increase the resolution of any model scanned at a low resolution by transferring skin from a higher resolution model. Our method shows successful manipulation of the minute structure of 3D skin differently from other methods such as Normal Mapping, Displacement Mapping, Displaced Subdivision Surfaces, and Normal Meshes where none of these techniques show manipulation of minute structure like ours and only approximation is used while our method recovers the original structure.

title: Grappa: A GRAPh PAckage in Java
abstract: Grappa is an extensible graph drawing package written in Java. The package comprises classes that implement graph representation, presentation and layout services. It provides an application programming interface (API) on top of which Web-based applications that need to visualize information in terms of graphs, such as process flows, business workflows or program dependencies, can be built. Through subclassing, the classes that implement an application inherit graph drawing and layout services provided by Grappa, these services can be enhanced and customized for the specific application. To illustrate its utility, a new version of Improvise, a multimedia process modeling environment, was written on top of Grappa.

title: Trees, windows and tiles for wavelet image compression
abstract: We investigate the task of compressing an image by using different probability models for compressing different regions of the image. In an earlier paper, we introduced a class of probability models for images, the k-rectangular tiling of an image, which is formed by partitioning the image into k rectangular regions and generating the coefficients within each region by using a probability model selected from a finite class C of probability models. We also describe a computationally efficient sequential probability assignment algorithm that is able to code an image with a code length that is close to the code length produced by the best model in the class. In this paper, we investigate the performance of the algorithm experimentally on the task of compressing wavelet subbands. We compare the method with compression methods that aim to compress as well as the best pruning of a quadtree and compression methods that exploit the local statistics in a window around the coefficient being compressed. For a class C consisting of a small number of Laplacian distributions and the uniform distribution, we find that the best tiling method works best, but the difference in performance is significant for only a few of the images tested.

title: A cooperative intrusion detection system for ad hoc networks
abstract: Mobile ad hoc networking (MANET) has become an exciting and important technology in recent years because of the rapid proliferation of wireless devices. MANETs are highly vulnerable to attacks due to the open medium, dynamically changing network topology, cooperative algorithms, lack of centralized monitoring and management point, and lack of a clear line of defense. In this paper, we report our progress in developing intrusion detection (ID) capabilities for MANET. Building on our prior work on anomaly detection, we investigate how to improve the anomaly detection approach to provide more details on attack types and sources. For several well-known attacks, we can apply a simple rule to identify the attack type when an anomaly is reported. In some cases, these rules can also help identify the attackers. We address the run-time resource constraint problem using a cluster-based detection scheme where periodically a node is elected as the ID agent for a cluster. Compared with the scheme where each node is its own ID agent, this scheme is much more efficient while maintaining the same level of effectiveness. We have conducted extensive experiments using the ns-2 and MobiEmu environments to validate our research.

title: Anomaly detection using call stack information
abstract: The call stack of a program execution can be a very good information source for intrusion detection. There is no prior work on dynamically extracting information from the call stack and effectively using it to detect exploits. In this paper we propose a new method to do anomaly detection using call stack information. The basic idea is to extract return addresses from the call stack, and generate an abstract execution path between two program execution points. Experiments show that our method can detect some attacks that cannot be detected by other approaches, while its convergence and false positive performance is comparable to or better than the other approaches. We compare our method with other approaches by analyzing their underlying principles and thus achieve a better characterization of their performance, in particular on what and why attacks will be missed by the various approaches.

title: Interfacing Oz with the PCTE OMS: A Case Study of Integrating a Legacy System with a Standard Object Management System
abstract: The integration of a legacy system and a standard Object Management System (OMS) is often a very challenging task. This paper details a case study, our experiment in interfacing Oz with the PCTE (Portable Common Tool Environment) Object Management System. Oz is a multi-user process-centered software development environment that has been under development in our lab since 1987, originally under the name Marvel. PCTE is a specification that defines a language-independent interface providing support mechanisms for software engineering environments (SEE). One of the premises of PCTE is that, in theory, an SEE such as Oz can be built (or extended) using the services provided by PCTE. The purpose of our experiment was to study how a legacy system such as Oz can be integrated into a new environment framework, e.g., PCTE. The architecture of the legacy system and the services of the framework are the key factors in the integration approach. Because Oz historically has included a native OMS, our experiment focused on modifying Oz to use the PCTE OMS, which has an open and standard API. This paper describes how several Oz components were changed to interface to the PCTE OMS. The resulting proof-of-concept hybrid system has process control and integration services provided by Oz, and data integration services provided in part by PCTE. We discuss in depth the solutions to the concurrency control problems that arise in such an environment, where Oz and PCTE use different approaches to transaction management (i.e., each has its own transaction manager). The PCTE implementation used in our experiment was the Emeraude PCTE V 12.5.1, and the Oz version was V 1.0.1.