Automatic 3D Scan Matching

Since the relative orientation of multiple reliefs is usually not known a priori in the desired accuracy, these reliefs have to be merged in one coordinate system. This process -also known as scan matching since it originally referred to the orientation of scans from laser triangulation systems- is called registration. The geometric structure of overlapping 3D reliefs that correspond to a single shape has to be considered for registration. In general, scan matching approaches can be classified into two categories:

1. Matching as an optimization problem uses a cost function to evaluate the quality of the 3D scan alignment. The range images are registered by determining the rigid transformation (rotation and translation) which minimizes the cost function.
2. Feature based matching extracts distinguishing features of the range images and uses corresponding features for calculating the alignment the reliefs.