Image-Based Rendering for Teleconference Systems

To obtain an image-based immersive presence in a virtual world, two important factors should be considered: system configuration and multiview representation. We present two non-adversary system configurations. The first is the well-known convergent wide-baseline set-up while the second is a unique proposal under investigation at our institute, which is based around a parallel multiple narrow-baseline camera set-up. In the domain of multiview representation we introduce two non-conflicting representations that can be implemented independent of the chosen system configuration, dependent on whether compression or scalability is important to the overall system. We then discuss our implementation of an image-based rendering system for an immersive teleconferencing application where three conferees meet around a shared virtual table. The system uses a wide-baseline configuration with two stereo camera pairs capturing the reference images. The system is designed to deal with hand gestures as well as the synthesis of areas occluded in one or more of the reference images but required in the derived view. We introduce the notion of a confidence map designed to indicate, for the derived image, which reference image should provide the required texture and disparity information for a surface.

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