#### Transcript A Method for Registration of 3D Surfaces ICP Algorithm

```A Method for Registration of 3D
Surfaces
ICP Algorithm
Erhan Avinal
Introduction
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Building 3D models of real world objects
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Data capture using range camera
Registration
Data merge
Registration - Goal
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To transform sets of
surface measurements
into a common
coordinate system
A model shape and a
data shape
Registration
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If we know correct correspondences, we can
find correct translation and rotation
Registration
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Issue : Finding corresponding points
ICP : Assume closest points correspond to
each other, compute the best transform
Rotation and translation
ICP Algorithm
Can be used with
Distance
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Euclidian distances
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Point to point set
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Point to line segment
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Point to triangle
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Point to parametric entity
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Point to implicit entity
Algorithm
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Point Set P with Np points, model shape X
Iterate until convergence
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Compute closest points
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Squared Euclidian distances
Compute registration (rotation and translation)
Apply the registration
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New point set
Other Issues
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Color matching
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Sharp, 2002
Godin, 1995
Johnson, 1997
Orientation
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Godin 2001
Schutz 1998
Other Issues
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Weighting
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Initial point selection
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Important nodes
Uniform sampling
Random
Select in regions of high curvature
k-d trees to find closest points
Results
Results
Results
Results
Results
Conclusions
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ICP can register a data shape to a model
shape
Independent of shape representation
Does not require preprocessing of 3D data
A good initial estimate of transformation is
required
High computation cost
Future Work
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Computational speedup
Parallel testing
Allow deformations
References
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Original Paper:
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P.J. Besl, N.D. McKay,A Method of Registration of 3D
Shapes, 1992
T. Jost, Fast Geometric Matching for Shape
Registration, 2002
S.M. Rusinkiewicz, Real time Acquisition and
Rendering of Large 3D Models, 2001
http://www.ee.surrey.ac.uk/Research/VSSP/3DVisio
n/model_building/model.html
Thanks
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