Friday, July 14, 2006

Virtual Heads

A team of psychologists has been studying the use of virtual heads (that is, images of heads generated using computers) for eyewitness identification. For instance, in one study, subjects watched video clips of human faces; later they looked at pairs of images to pick which one was of a face they'd seen in a clip. Some of the images were photos and some were screen-shots of virtual models. Jeremy N. Bailenson, Andrew C. Beall & Jim Blascovich, Using Virtual Heads for Person Identification: An Empirical Study Comparing Photographs to Photogrammetrically-Generated Models, 53 J. Forensic Identification 722-728 (2003).

The authors point to potential advantages of this technology over standard line-ups and photo arrays:

[U]sing virtual heads for conducting police lineups (as opposed to either live lineups or photograph lineups) has three major advantages. First, the witness or identifier has the opportunity to explore the suspect at any possible viewing angle or distance while maintaining complete anonymity. Second, by using morphing techniques, the designer of the lineup can easily manufacture an infinite set of distracter heads (i.e., the virtual foils in the lineup) that are dissimilar to the suspect’s head. Third, using animation sequences, the lineup conductor can render any facial expression or verbal utterance from the virtual head. Because of the advantages, it is possible to conduct lineups that are more realistic than when using mere photographs.
For more on virtual reality and eyewitness identification, see this page from the Research Center for Virtual Environments and Behavior (UC Santa Barbara), where authors Andrew Beall and Jim Blascovich are co-directors.

The lead author, Jeremy Bailenson, is at Stanford's Virtual Human Interaction Lab. He has also worked on projects using virtual reality in other courtroom applications, including witness preparation and scene re-enactment. See list of publications (the law-related ones are at the bottom of the page).

Image from Research Center for Virtual Environments and Behavior. Used with permission.

Categories: , , , , , , , , ,

No comments: