Open Access

Parameterized Facial Expression Synthesis Based on MPEG-4

  • Amaryllis Raouzaiou1Email author,
  • Nicolas Tsapatsoulis1,
  • Kostas Karpouzis1 and
  • Stefanos Kollias1
EURASIP Journal on Advances in Signal Processing20022002:521048

Received: 25 October 2001

Published: 22 October 2002


In the framework of MPEG-4, one can include applications where virtual agents, utilizing both textual and multisensory data, including facial expressions and nonverbal speech help systems become accustomed to the actual feelings of the user. Applications of this technology are expected in educational environments, virtual collaborative workplaces, communities, and interactive entertainment. Facial animation has gained much interest within the MPEG-4 framework; with implementation details being an open research area (Tekalp, 1999). In this paper, we describe a method for enriching human computer interaction, focusing on analysis and synthesis of primary and intermediate facial expressions (Ekman and Friesen (1978)). To achieve this goal, we utilize facial animation parameters (FAPs) to model primary expressions and describe a rule-based technique for handling intermediate ones. A relation between FAPs and the activation parameter proposed in classical psychological studies is established, leading to parameterized facial expression analysis and synthesis notions, compatible with the MPEG-4 standard.


facial expressionMPEG-4 facial definition parametersactivationparameterized expression synthesis

Authors’ Affiliations

Department of Electrical and Computer Engineering, National Technical University of Athens, Zographou, Greece


© Raouzaiou et al. 2002