Factorization-based Hierarchical Reconstruction for Circular Motion

A new practical method is developed for 3D reconstruction from an image sequence captured by a camera with constant intrinsic parameters undergoing circular motion. We introduce a method for enforcing the circular constraint in a factorization-based projective reconstruction. This is called a circular projective reconstruction. Given a turntable sequence, our method uses a hierarchical approach to reconstructing the objects and cameras, which first computes a circular projective reconstruction of a sub-sequence and then extends the reconstruction to the complete sequence. Camera matrix and the motion parameters, i.e. the rotation angles, are computed iteratively in a way that minimizes the 2D reprojection error. Thus, an optimal reconstruction is obtained upon convergence. The algorithm is evaluated using real image sequence.