METHOD AND APPARATUS FOR ACCURATE ALIGNMENT OF IMAGES IN DIGITAL IMAGING SYSTEMS BY MATCHING POINTS IN THE IMAGES CORRESPONDING TO SCENE ELEMENTS

A digital imaging system is described that facilitates the location of anchors or targets in images of a scene. In one aspect, the digital imaging system makes use of differences as between the properties of the surfaces of the targets and the properties of the surfaces of the objects that are to be mensurated, reconstructed, etc., to facilitate providing uniform illumination of the targets when recording a set of images of the scene, thereby reducing noise that may arise in connection with determining the locations of the targets if they were illuminated by structured illumination, while contemporaneously providing that the objects can be illuminated by structured illumination when the images are recorded. In this aspect, the digital imaging system can use the positions of the targets in the images to relate a local coordinate system associated with the image set to a global coordinate system. In a second aspect, the digital imaging system makes use of one or more of a plurality of algorithms to determine the locations of targets in the images of the scene in the respective objects. In this aspect, the digital imaging system records two sets of images, including a baseline set and a working set. The baseline set is recorded using uniform illumination, with the baseline set comprising only images of the targets. The working set is recorded using structured illumination, with the working set comprising image of both the targets and the objects. The working set is used in connection with mensuration, virtual reconstruction, etc., and one or more of the algorithms are used to determine the likely positions of the targets in the images in the working image set, and to determine transformations between the baseline and working image set such that the local coordinate system associated with the working image set can be related to the global coordinate system.