TR-04-04: Projective Space Temporal Synchronization of Multiple Video Sequences

Abstract

In this work, we present a novel method to temporally synchronize multiple stationary video cameras with overlapping views. The method uses a two stage approach that first approximates the synchronization by tracking moving objects and identifying inflection points. The method then proceeds to refine the estimate using a consensus based matching heuristic to find frames that best agree with the pre-computed camera geometries from stationary image features. By using the fundamental matrix and the trifocal tensor in the second refinement step, we improve the estimation of the first step and handle a broader range of input scenarios and camera conditions. The method is simple compared to current techniques and is no harder than feature tracking in stage one and computing accurate geometries in stage two. We also provide a robust method to assist synchronization in the presence of inaccurate geometries.