1. A Method for Registration of 3D Surfaces ICP Algorithm
Erhan Avinal

2. Introduction Building 3D models of real world objects
Data capture using range camera
Registration
Data merge

3. Registration - Goal
To transform sets of surface measurements into a common coordinate system
A model shape and a data shape

4. Registration
If we know correct correspondences, we can find correct translation and rotation

5. Rotation and translation
Registration
Issue : Finding corresponding points
ICP : Assume closest points correspond to each other, compute the best transform
Rotation and translation

6. ICP Algorithm
Can be used with

7. Distance Euclidian distances Point to point set Point to line segment
Point to triangle
Point to parametric entity
Point to implicit entity

8. Algorithm Point Set P with Np points, model shape X
Iterate until convergence
Compute closest points
Squared Euclidian distances
Compute registration (rotation and translation)
Apply the registration
New point set

9. Other Issues Color matching Orientation Sharp, 2002 Godin, 1995
Johnson, 1997
Orientation
Godin 2001
Schutz 1998

10. Other Issues Weighting Initial point selection
Important nodes
Initial point selection
Uniform sampling
Random
Select in regions of high curvature
k-d trees to find closest points

11. Results

12. Results

13. Results

14. Results

15. Results

16. Conclusions 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

17. Future Work
Computational speedup
Parallel testing
Allow deformations

18. References Original Paper:
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

19. Thanks