Animating Virtual Signers: The Issue of Gestural Anonymization

This paper presents an ongoing PhD research project on visual perception and motion analysis applied to virtual signers (virtual agents used for Sign Language interaction). Virtual signers (or signing avatars) play an important role in the accesibility of information in sign languages. They have been developed notably for their capability to anonymize shape and ap-pearance of the content producer. While motion capture provides human-like, realistic and comprehensible signing animations, it also arises the question of anonymity. Human body movements contain important information about a person's identity, gender or emotional state. In the present work, we want to address the problem of gestural identity in the context of animated agents in French Sign Language. On the one hand, the ability to identify a person from signing motion is assessed through psychophysical experiments, using point-light displays. On the other hand, a computational framework is developed in order to investigate which features are critical for person identification and to control them over the virtual agent.

[1]  Bastien Berret,et al.  Collecting and Analysing a Motion-Capture Corpus of French Sign Language , 2016 .

[2]  U. Bellugi,et al.  Perception of American sign language in dynamic point-light displays. , 1981, Journal of experimental psychology. Human perception and performance.

[3]  G. Mather,et al.  Gender discrimination in biological motion displays based on dynamic cues , 1994, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[4]  Alice J. O'Toole,et al.  Low-dimensional representation of faces in higher dimensions of the face space , 1993 .

[5]  Michael Filhol,et al.  KAZOO: a sign language generation platform based on production rules , 2016, Universal Access in the Information Society.

[6]  N. Troje,et al.  Embodiment of Sadness and Depression—Gait Patterns Associated With Dysphoric Mood , 2009, Psychosomatic medicine.

[7]  Thierry Dutoit,et al.  Expressive Gait Synthesis Using PCA and Gaussian Modeling , 2010, MIG.

[8]  Martin A. Giese,et al.  Morphable Models for the Analysis and Synthesis of Complex Motion Patterns , 2000, International Journal of Computer Vision.

[9]  A. O'Toole,et al.  Simulating the ‘Other-race Effect* as a Problem in Perceptual Learning , 1991 .

[10]  N. Troje.  Decomposing biological motion: a framework for analysis and synthesis of human gait patterns. , 2002, Journal of vision.

[11]  G. Johansson.  Visual perception of biological motion and a model for its analysis , 1973 .

[12]  Lars Omlor,et al.  Features in the Recognition of Emotions from Dynamic Bodily Expression , 2009 .

[13]  Evguenia Malaia,et al.  Analysis of ASL Motion Capture Data towards Identification of Verb Type , 2008, STEP.

[14]  Lars Omlor,et al.  Extraction of spatio-temporal primitives of emotional body expressions , 2006, Neurocomputing.

[15]  R. Würtz,et al.  The little difference: Fourier based synthesis of gender- specific biological motion , 2002 .

[16]  Nicoletta Adamo-Villani,et al.  Effects of Character Geometric Model on Perception of Sign Language Animation , 2009, 2009 Second International Conference in Visualisation.

[17]  Sylvie Gibet.  Building French Sign Language Motion Capture Corpora for Signing Avatars , 2018 .

[18]  Maggie Shiffrar,et al.  Experience, context, and the visual perception of human movement. , 2004, Journal of experimental psychology. Human perception and performance.

[19]  Kenneth C. Knowlton,et al.  Perception of sign language from an array of 27 moving spots , 1981, Nature.

[20]  Annelies Braffort,et al.  Toward the Study of Sign Language Coarticulation: Methodology Proposal , 2009, 2009 Second International Conferences on Advances in Computer-Human Interactions.

[21]  N. Troje,et al.  Person identification from biological motion: Effects of structural and kinematic cues , 2005, Perception & psychophysics.

[22]  G Johansson,et al.  Spatio-temporal differentiation and integration in visual motion perception , 1976, Psychological research.

[23]  Evie Malaia,et al.  Kinematic parameters of signed verbs. , 2013, Journal of speech, language, and hearing research : JSLHR.

[24]  M. Shiffrar,et al.  Recognizing people from their movement. , 2005, Journal of experimental psychology. Human perception and performance.

[25]  Coralie Vincent,et al.  Variation prosodique et traduction poétique (LSF/français) : Que devient la prosodie lorsqu'elle change de canal ? (Prosodic variation and poetic translation (LSF/French): What happens to prosody with a channel change?) , 2016, JEP-TALN-RECITAL.

[26]  Alexis Héloir,et al.  Sign Language Avatars: Animation and Comprehensibility , 2011, IVA.

[27]  Alexis Héloir,et al.  Assessing the deaf user perspective on sign language avatars , 2011, ASSETS.

[28]  J. Cutting,et al.  Recognizing the sex of a walker from a dynamic point-light display , 1977 .

[29]  J. Cutting,et al.  Temporal and spatial factors in gait perception that influence gender recognition , 1978, Perception & psychophysics.

[30]  J. Cutting,et al.  Recognizing friends by their walk: Gait perception without familiarity cues , 1977 .