Many computer applications depend on the visual realism of virtual human character motion. Unfortunately, it is difficult to describe what makes a motion look real yet easy to recognize when a motion looks fake. These characteristics make synthesizing motions for a virtual human character a difficult challenge. A potentially useful approach is to synthesize high-quality, nuanced motions from a database of example motions. Unfortunately, none of the existing example-based synthesis techniques has been able to supply the quality, flexibility, efficiency and control needed for interactive applications, or applications where a user directs a virtual human character through an environment. At runtime, interactive applications, such as training simulations and video games, must be able to synthesize motions that not only look realistic but also quickly and accurately respond to a user’s request. This dissertation shows how motion parameter decoupling and highly structured control mechanisms can be used to synthesize high-quality motions for interactive applications using an example-based approach. The main technical contributions include three example-based motion synthesis algorithms that directly address existing interactive motion synthesis problems: a method for splicing upper-body actions with lower-body locomotion, a method for controlling character gaze using a biologically and psychologically inspired model, and a method for using a new data structure called a parametric motion graph to synthesize accurate, quality motion streams in realtime.

@PhdThesis{Hec07,
  author       = "Heck, Rachel",
  title        = "Automated Authoring of Quality Human Motion for Interactive Environments",
  school       = "University of Wisconsin Madison",
  year         = "2007",
  ee           = "http://pages.cs.wisc.edu/~heckr/Thesis/",
  url          = "http://graphics.cs.wisc.edu/Papers/2007/Hec07"
}