Camera tracking based on circular point factorization

Concentric circles (C
²
Tag's) are planar markers which offer great advantages for detection and tracking. As the circular point-pair (CPP) is the geometric information encoded by a C
²
Tag, this work is focused on factorization techniques for Structure-and-Motion from multiple CPP images. Gathering all of them in a measurement matrix, two issues are addressed: how to scale the existing entries and how to fill the missing ones. We describe a complete algorithm and prove it. We validate our contributions on simulated and real images.