Harnessing Mobile Ubiquitous Video

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Harnessing Mobile Ubiquitous Video
Neil J. McCurdy, Jennifer N. Carlisle, William G.
Griswold Department of Computer Science and
Engineering University of California, San
Diego nemccurd, jcarlisl, wgg_at_ucsd.edu
Reality Flythrough
How it Works
A transition provides the user with a dynamic
conversion from one camera to the next while also
providing a model of the virtual space to give
the user a spatial context For
transitions across a wide area(as shown above),
composite transitions are formed by piecing
together a series of simple transitions to
provide the user with a unique view that supplies
the necessary context and distance Conveys the
idea of distance traveled between cameras
Provides to the user a virtual floor grid that
visually displays the distance between
cameras Duration of the transition is
proportional to the distance traveled
Embracing the idea of ubiquity, RealityFlythrough
has the ability to harness video streams, such
as camera cell phones or webcams, without prior
information about the scene RealityFlythrough
works because we only require knowledge of a
cameras position and orientation Position
is determined from GPS units or other locating
infrastructure Orientation is taken
from a compass and inclinometers Demands
no standard of camera quality Eliminates the
need for advance spatial knowledge Allows
the system to be utilized by first responders in
disaster situations who may enter an area
whose floor plan, if previously known,
has changed dramatically RealityFlythrough is
successful as a real-time live telepresence
system because it taps into the power of the
human visual system Offloads many
processing requirements to the user
Reveals rather than conceals defects so that the
user can make the necessary cognitive
connections Makes real-time exploration of
a live scene possible
Experimental Results
Subjects were given either a short video of a
transition or two still images and had to select
a birdseye depiction that best represented their
position in the space Transitions were
determined to be more effective in conveying
information about the spatial relationships
between cameras Provided a quicker understanding
of the space through a first-person immersion
With transitions subjects reported a feeling
of learning the area
86.67 of subjects had a greater or equal score
on transition questions Success rate on
answering transition questions increased as
subjects saw more transitions Subjects
also increased answering speed
Comprehension for expert users was shown to
approach 100 In the location familiar
to the subjects the second to last and
last questions were answered correctly 93.33 and
100 of the time respectively
Demonstrates that this is a learnable skill