estimateRigidTransform

estimate the rigid transformation between two sets of 3D point clouds, given a set of point matches

Description

This is a simple utility for estimating the rigid transformation that aligns two sets of 3D point clouds, given 3 (or more) point matches.

Input: two sets of 3D point clouds (P1 and P2)
Output: homogeneous transformation that aligns the two clouds
Assumptions:
1- point i in the first point cloud corresponds to point i in the second cloud
2- the transformation is rigid (i.e. only a rotation and a translation)
3- you need at least 3 (non-degenerate) point matches (i.e. they don't lie on a straight line)

The math is basic and well-known. The point of this upload is just to save the little bit of time it would've taken you to code it yourself.

Reference: "Computer Vision, a modern approach" by Forsyth and Ponce

Related:
1- Click3dPoint (on the File Exchange) to manually find a few point correspondences
2- ICP (e.g. Matlat implementation by A. Mian)

Acknowledgements

The author wishes to acknowledge the following in the creation of this submission:
Click3dPoint

• MATLAB release: MATLAB 7.9 (2009b)

[Janti]

Great work.
Correct me if I'm wrong but I think line 28 should read

alignedP1h = estT * P1h;

instead of

alignedP1h = T * P1h;

[Babak Taati]

Thanks Janti. You're correct. I fixed it.

[Andreas]