Interactive
Model Reconstruction with User Guidance [Home][2009 ISMAR
(2.4MB)][Longer Version (5.6MB)][Poster (1.9MB)]
Generating 3D
models of real world objects is a common task during development of any
augmented reality application. This paper describes how ProFORMA
(Probabilistic Feature-based On-line Rapid Model Acquisition), a rapid
reconstruction system, has been designed to simplify and speed up this
task. ProFORMA uses a fixed video camera to allow on-line
reconstruction of objects held in a user's hand. Partial models are
generated very quickly and displayed instantly, allowing the user to
plan how to manipulate the object's pose in order to generate
additional views for reconstruction. We demonstrate how augmented
reality can be used to assist the user in view planning, guiding the
user to collect new keyframes from desirable views in order to complete
and refine the model.
Figure
1: The viewing sphere of the object is discretised into an
icosahedron.
Unseen faces on the model increase the uncertainty score of icosahedron
faces (views) in the direction of the normal, whereas camera views
decrease the uncertainty score of isocahedron faces. Icosahedron faces
(views) with high uncertainty are coloured red, and low uncertainty
green. A 3D arrow is augmented onto the object showing the user which
way to rotate the object. Left:
(a)
First phase of user guidance - the user is guided to continue the
current rotation if it will visit views with high uncertainty in the
near future. Camera positions of previous keyframes are shown in green.
Extrapolated camera positions if the current rotation is continued are
shown in cyan. If extrapolated camera positions intersect highly
uncertain faces in the next 90 degrees, the user is asked to continue
the current rotation, otherwise the second phase of user guidance is
initiated. Right: (b)
Second
phase of user guidance - the user is guided to the most uncertain view
(shown in cyan). The user continues to be guided to this face until the
uncertainty is below a threshold, at which point the user is then
guided to the face which now has highest uncertainty. Once all faces
have an uncertainty level below a threshold, reconstruction is complete
and keyframe acquisition is halted.
Contact Information
Email:
Address:
Department of Engineering. University of Cambridge
Trumpington Street, Cambridge CB2 1PZ
