The objects which are considered can be rather general, including a living being or body parts, e.g., a head or hands.
[3] Another approach is to register a 3D CAD model over the photograph of a known object by optimizing a suitable distance measure with respect to the pose parameters.
The main idea is to determine the correspondences between 2D image features and points on the 3D model curve.
Systems exist which use a database of an object at different rotations and translations to compare an input image against to estimate pose.
These systems accuracy is limited to situations which are represented in their database of images, however the goal is to recognize a pose, rather than determine it.