3D Audiovisual Rendering and Real-Time Interactive Control of Expressivity in a Talking Head

The integration of virtual agents in real-time interactive virtual applications raises several challenges. The rendering of the movements of the virtual character in the virtual scene (locomotion of the character or rotation of its head) and the binaural rendering in 3D of the synthetic speech during these movements need to be spatially coordinated. Furthermore, the system must enable real-time adaptation of the agent’s expressive audiovisual signals to user’s on-going actions. In this paper, we describe a platform that we have designed to address these challenges as follows: (1) the modules enabling real time synthesis and spatial rendering of the synthetic speech, (2) the modules enabling 3D real time rendering of facial expressions using a GPU-based 3D graphic engine, and (3) the integration of these modules within an experimental platform using gesture as an input modality. A new model of phoneme-dependent human speech directivity patterns is included in the speech synthesis system, so that the agent can move in the virtual scene with realistic 3D visual and audio rendering. Future applications of this platform include perceptual studies about multimodal perception and interaction, expressive real time question and answer system and interactive arts.