Robust marker-based projector–camera synchronization

Recording clean pictures of projected images requires the projector and camera to be synchronized. This task usually requires additional hardware or imposes major restrictions on the devices with software-based approaches, e.g., a specific frame rate of the camera. We present a novel software-based synchronization technique that supports projectors and cameras with different frame rates and at the same time tolerates camera frame drops. We focus on the special needs of LCD projectors and the effect of their liquid crystal response time on the projected image. By relying on visible marker detection we entirely refrain from taking time measurements, allowing for a robust and fast synchronization.