Investigating the Suitability of a Software Capture Trigger in a 3D Reconstruction System for Telepresence

In this paper we examine how closely together images to be used in 3D reconstruction are captured, when acquisition is started using a software-based trigger delivered to multiple computers on a network. In addition we compare a software triggered pull system to a push system. Synchronisation is a key component in 3D reconstruction systems and can also be one of the most problematic. In a shape-from-silhouette based system, images are captured at the same moment to ensure the position of the object is consistent in all frames. Differences in position between captured frames results in deformations such as holes and missing or extended features. By capturing images of a projected clock, we can tell with around 10ms granularity, how closely together images are captured. This gives us an indication of whether software capture triggers delivered over a network can be used for image acquisition in a 3D reconstruction system, instead of hardware synchronised capture.