Leveraging technology for research.

In a computerized method, the three-dimensional structure of an object is recovered from a closed-loop sequence of two-dimensional images taken by a camera undergoing some arbitrary motion. In one type of motion, the camera is held fixed, while the object completes a full 360 DEG rotation about an arbitrary axis. Alternatively, the camera can make a complete rotation about the object. In the sequence of images, feature tracking points are selected using pair-wise image registration. Ellipses are fitted to the feature tracking points to estimate the tilt of the axis of rotation. A set of variables are set to fixed values while minimizing an image-based objective function to extract a set of first structure and motion parameters. Then the set of variables freed while minimizing of the objective function continues to extract a second set of structure and motion parameters that are substantially the same as the first set of structure and motion parameters.