In the classical approach, called autocalibration or self-calibration, camera motion and parameters are recovered first, using rigidity; then structure is easily computed. Recently, new methods based on the idea of stratification have been proposed. They upgrade the projective structure, achievable from correspondences only, to the Euclidean structure, by exploiting all the available constraints.
The contribution of this paper is to give a critical, unified view of some of the most promising techniques. Such a comparative account sheds light on the relations between different methods, presented in different ways and formalisms in the original research articles.
This document have been adapted from [11].