Automatic alighnment of elecron tomography images using markers

摘要

Electron tomography means recnstructing the interior of an object from its electron microscpe images. In order to successfully perform the 3D reconstruction, the motion between consencutive images must be solved, i.e., the images have to be aligned or registered. Using a set of two-dimensional electron microscope images of a three-dimensional object, we propose a method where the registration is automated using small colloidal gold particles as reference markers between images. The alignment problem is divided into several subproblems: (1) Finding initial mathces from successive images, (2) estimating the epipolar geometry between images, (3) finding and localizing the glod particles with subpixel accuracy in each image, (4) predicting the probable matching goold particles using the epipolar geometry with the disparity information, (5) matching and tracking the gold particles through the tilt series, and (6) optimizing the transformation parameters for the whold image set. The results show the reliability of the suggested method as well as high accuracy in registration.