SocialSync: Sub-Frame Synchronization in a Smartphone Camera Network

SocialSync is a sub-frame synchronization protocol for capturing images simultaneously using a smartphone camera network. By synchronizing image captures to within a frame period, multiple smartphone cameras, which are often in use in social settings, can be used for a variety of applications including light field capture, depth estimation, and free viewpoint television. Currently, smartphone camera networks are limited to capturing static scenes due to motion artifacts caused by frame misalignment. To overcome this synchronization challenge, we first characterize frame capture on Android devices by analyzing the statistics of camera setup latency and frame delivery to the software application. Next, we develop the SocialSync protocol to achieve sub-frame synchronization between devices by estimating frame capture timestamps millisecond accuracy. Finally, we demonstrate the effectiveness of SocialSync on mobile devices by reducing motion-induced artifacts when recovering the light field.