CS Seminar
Wednesday, February 4, 2004
10:30, ST2 Room 430

Resolving Multiple Occluded Layers in Augmented Reality

Dr. J. Edward Swan II
Naval Research Laboratory

Abstract:

A useful function of augmented reality (AR) systems is their ability
to visualize occluded infrastructure directly in a user's view of the
environment.  This is especially important for our application
context, which utilizes mobile AR for navigation and other operations
in an urban environment.  A key problem in the AR field is how to best
depict occluded objects in such a way that the viewer can correctly
infer the depth relationships between different physical and virtual
objects.  Showing a single occluded object with no depth context
presents an ambiguous picture to the user.  But showing all occluded
objects in the environments leads to the  ``Superman's X-ray vision''
problem, in which the user sees too much information to make sense of
the depth relationships of objects.

Our efforts differ qualitatively from previous work in AR occlusion,
because our application domain involves \EM{far-field} occluded
objects, which are tens of meters distant from the user.  Previous
work has focused on \EM{near-field} occluded objects, which are within
or just beyond arm's reach, and which use different perceptual cues.
We designed and evaluated a number of sets of display attributes.  We
then conducted a user study to determine which representations best
express occlusion relationships among far-field objects.  We identify
a drawing style and opacity settings that enable the user to
accurately interpret three layers of occluded objects, even in the
absence of perspective constraints.
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BioDr. J. Edward Swan II is a Computer Scientist with the Virtual Reality
Lab
at the Naval Research Laboratory.  Dr. Swan's research has been
broad-based, centering on the topics of human-computer interaction, human
factors, virtual and augmented reality, visualization, and graphics.  Dr.
Swan is a scientist with the Naval Research Laboratory, where he works in
the Virtual Reality Lab ­ an institution which is widely known for its
innovations in augmented and virtual reality.  Dr. Swan has lead research
efforts in user interface and human factors techniques, including the
perception of occluded objects in augmented reality, navigation and
manipulation in virtual reality, the perception of color and texture in
desktop displays, and an interface for visualizing brain and cranial base
tumors.  He has also been active in formalizing usability engineering
methodologies and evaluation techniques for augmented and virtual
reality.  In computer graphics, he has investigated algorithms for
efficient and accurate rendering of volumetric datasets, rendering
architectural datasets for virtual reality applications, and image-based
rendering techniques for efficient terrain visualization.  Dr. Swan's
current work is motivated by the problem domain of worn and desktop
systems for command and control and battlefield visualization; previous
motivating problem domains include biomedical visualization, terrain rendering,
virtual reality, and empirical studies of software systems.  Dr. Swan is
active in the IEEE Visualization conference; he has served on the
conference committee for eight years, including Program Co-Chair in 2001
and 2002.  Dr. Swan is a member of ACM, SIGGRAPH, SIGCHI, IEEE, and the
IEEE Computer Society.