System for multiple projector-based tiled video playbacks

To obtain large scale displays tiled video projections are often used. In this paper we present a system for planar tiled video projection based on client server architecture. The system performs following actions: projector calibration, video transformation and video playback. To perform above actions several problems have to be addressed. Calibration of multiple projectors is based on automatic computing of spatial relations between projecting surface plane and each projector image plane using predefined calibration patterns. Transformation of video includes geometric transformation using homography matrices and lighting correction to achieve smooth transitions between each projector image. Finally, videos from all projectors have to be synchronized. In the current client server architecture, a single client performs off-line calibration, video transformation and distribution to clients. The server synchronizes all video playbacks on arbitrary number of clients and the process is designed to be hardware and software independent. Each client handles storage and playback of transformed video. Current implementation of the system performs computationally intensive video processing on a multi-core CPU or NVIDIA GPUs. The system development has been done on several platforms including OpenCV, QT and CUDA.