Expressive textures

ABSTRACT

If a moving image is more expressive than words or than a still image, then an animated facial expression can explain more in depth the feelings of a virtual character. Facial animation has been used in many applications, from entertainment to research on virtual humans and tele-presence. The aim of most of the approaches is to achieve high degrees of realism of virtual characters and is supplemented by complex models of kinematics, muscle movement, movement of clothing as well as cognition and behavioral models. Video avatars and image-based techniques are also used for creating virtual humans. However, the complexity of the geometric and physically simulated facial models used by the above methods make them unsuitable for use in distributed collaborative virtual environments running on low bandwidth networks or over the internet. Therefore, the majority of approaches for such environments are using simplified models of virtual human, which the obvious disadvantage of lower degrees of realism.The Reflective Textures method, presented in this paper, makes use of textures of images of both synthetic faces or faces captured from video and of a simple low-polygon face/head model. It provides an interactive way of fine-tuning and adjusting the underlined model to allow a more realistic mapping for a specific facial image. Furthermore, it concentrates in creating facial expressions by manipulation of the texture. Facial Expressions such as Fear, Happiness, Melancholy or Surprise, blinking of the eyes and movement of the pupils is automatically achieved for any mapped facial image by the system.

REFERENCES

• 1: Brooke, N.M. & Scott, S.D. Computer graphics animations of talking faces based on stochastic models, Proceedings of the International Symposium on Speech, Image-processing and Neural Networks, Hong Kong, 1994, IEEE, pages 73-76.
• 2: Marc Escher , Nadia Magnenat Thalmann, Automatic 3D Cloning and Real-Time Animation of a Human Face, Proceedings of the Computer Animation, p.58, June 04-07, 1997
• 3: Brian Guenter , Cindy Grimm , Daniel Wood , Henrique Malvar , Fredric Pighin, Making faces, Proceedings of the 25th annual conference on Computer graphics and interactive techniques, p.55-66, July 1998 [doi>10.1145/280814.280822]
• 4: Karpouzis K., Tsapatsoulis N., Kollias S. Moving to continuous facial expression space using the MPEG-4 facial definition parameter set, SPIE Electronic Imaging 2000, San Jose, CA, USA, January 2000.
• 5: Yuencheng Lee , Demetri Terzopoulos , Keith Walters, Realistic modeling for facial animation, Proceedings of the 22nd annual conference on Computer graphics and interactive techniques, p.55-62, September 1995 [doi>10.1145/218380.218407]
• 6: P. Maes , T. Darrell , B. Blumberg , A. Pentland, The ALIVE system: full-body interaction with autonomous agents, Proceedings of the Computer Animation, p.11, April 19-21, 1995
• 7: Nadia Magnenat Thalmann , Daniel Thalmann, Animating virtual actors in real environments, Multimedia Systems, v.5 n.2, p.113-125, March 1997 [doi>10.1007/s005300050047]
• 8: M. Nahas , H. Huitric , M. Rioux , J. Domey, Facial image synthesis using skin texture recording, The Visual Computer: International Journal of Computer Graphics, v.6 n.6, p.337-343, Dec. 1990 [doi>10.1007/BF01901020]
• 9: Frédéric Pighin , Jamie Hecker , Dani Lischinski , Richard Szeliski , David H. Salesin, Synthesizing realistic facial expressions from photographs, Proceedings of the 25th annual conference on Computer graphics and interactive techniques, p.75-84, July 1998 [doi>10.1145/280814.280825]
• 10: Keith Waters, A muscle model for animation three-dimensional facial expression, Proceedings of the 14th annual conference on Computer graphics and interactive techniques, p.17-24, August 1987
• 11: Stéphane Valente , Jean-Luc Dugelay, Face Tracking and Realistic Animations for Telecommunicant Clones, IEEE MultiMedia, v.7 n.1, p.34-43, January 2000 [doi>10.1109/93.839309]

INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Animation

Additional Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Virtual reality

General Terms:
Algorithms

Keywords:
Facial expressions, character animation, collaborative virtual environments, texture mapping