Extract projective homography from two Kinect depth maps

Question

Given two consecutive 3D point clouds 1 and 2 (not the whole cloud, say 100 points selected from the cloud with OpenCV\'s GoodFeaturesToMatch), obtained from a Kinect depthm

Answer 1

"The correct" algorithm to use for computing difference between two snapshots of 2D or 3D point clouds is called ICP (Iterative Closest Point). The algorithm solves

In human-readable-format: For given point sets P1 and P2 find the rotation matrix R and translation T that transforms P1 to P2. Just make sure they are normalized around their origin.

The algorithm is conceptually simple and is commonly used in real-time. It iteratively revises the transformation (translation, rotation) needed to minimize the distance between the points of two raw scans.

For those interested this is a topic within Computational Geometry Processing