An automated technique for real-time production of lifelike animations of American Sign Language


Generating sentences from a library of signs implemented through a sparse set of key frames derived from the segmental structure of a phonetic model of ASL has the advantage of flexibility and efficiency, but lacks the lifelike detail of motion capture. These difficulties are compounded when faced with real-time generation and display. This paper describes a technique for automatically adding realism without the expense of manually animating the requisite detail. The new technique layers transparently over and modifies the primary motions dictated by the segmental model and does so with very little computational cost, enabling real-time production and display. The paper also discusses avatar optimizations that can lower the rendering overhead in real-time displays.

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The authors would like to thank the Deaf experts and qualified interpreters for reviewing drafts of the animations. We are also grateful to the reviewers for their thoughtful comments and valuable feedback.

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Correspondence to John McDonald.

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McDonald, J., Wolfe, R., Schnepp, J. et al. An automated technique for real-time production of lifelike animations of American Sign Language. Univ Access Inf Soc 15, 551–566 (2016).

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  • Sign Language
  • Inverse Kinematic
  • American Sign
  • Inverse Kinematic Solution
  • Sign Synthesis