Mediaspaces have been designed to facilitate informal communication and support group awareness while assuring privacy protection. However, low bandwidth communication is a source of undesirable discontinuities in such systems, resulting in a loss of peripheral awareness. In addition, privacy is often implemented as an accessibility matrix coupled to an all-or-nothing exposure of personal state. In this article, we describe CoMedi, a mediaspace prototype that addresses the problem of discontinuity and privacy in an original way: computer vision and speech recognition are used in conjunction to minimize visual discontinuities while supporting free movements in a room. Privacy is maintained by publication filters at the desired level of transparency.

In this paper we present the Clover architectural model, a new conceptual architectural model for groupware. Our model results from the combination of the layer approach of Dewan's generic architecture with the functional decomposition of the Clover design model. The Clover design model defines three classes of services that a groupware application may support, namely, production, communication and coordination services. The three classes of services can be found in each functional layer of our model. Our model is illustrated with a working system, the CoVitesse system, its software being organized according to our Clover architectural model.

laurence.pasqualetti

The current solutions to disclosing privacy in computer-mediated communication are two-fold: either the connection is permitted and an audio-video link is opened providing a full-blown perceptual view on the distant location, or the connection is denied and the distant visitor has no perceptual access to the remote site. We claim that the disclosure of private data is more complex than these simplistic binary solutions. In this article, we present the concept of published observability as a system property to characterize the disclosure of private data. We propose a technical solution as an instantiation of this property using an eigen-space coding for private video data. This technique has been implemented within CoMedi, a mediaspace under development. KEY WORDS privacy, computer mediated communication, mediaspace, eigen-space coding, computer vision 1. INTRODUCTION Computer Mediated Communication (or CMC) covers multiple forms of person-to-person communication supported by a comput...