Droplet Tracking from Unsynchronized Cameras

We develop a method for reconstructing the three-dimensional (3D) trajectories of droplets in flight captured by multiple unsynchronized cameras. Triangulation techniques that underpin most stereo reconstruction methods do not apply in this context as the image streams recorded by different cameras are not synchronized. We assume instead a priori knowledge about the motion of the droplets to reconstruct their 3D trajectories given unlabelled two-dimensional tracks in videos recorded by different cameras. Our approach also avoids the challenge of accurately matching droplet tracks across multiple video frames. We evaluate the proposed method using both synthetic and real data.