Interactive Alignment of Parameterised Object Models to Images

Semi-automatic measurement of objects with regular shapes can be performed efficiently in three steps: (1) selection of an object model and approximate alignment of the object by a human operator, (2) precise alignment to the image by a fitting algorithm, and (3) correction of fitting errors by a human operator. This paper presents a new approach to perform these three steps using the same algorithm in all three steps. This algorithm allows the operator to drag both points and lines of the projected object model wire frame, including curved edges and contour edges, in order to align these features with the image contents. Using the described algorithm there is no need for the operator to specify which parameters of the object models are to be adapted in order to improve the alignment.