Secure Visible Light Communication via Two-Dimensional Spatially Aliased Patterns

Screen-camera communication has attracted considerable attention as a form of visible light communication (VLC) using commercial-off-the-shelf devices. Nonetheless, the security of screen-camera communications in mobile applications has largely been disregarded, despite the fact that information displayed on an open screen is easily intercepted. One-way communication systems also make it difficult to add security features. In this paper, we propose a secure screen-camera communication system in which a visual encryption algorithm is designed to camouflage transmitted images between the screen and camera. When the targeted receiver holds a camera in a designated viewing position (ie, directly in front of the screen at a distance of 50cm), the camouflaged image is revealed due to aliasing effect. From any other position, only the camouflaged image can be seen.

In Proceedings of the 13th International Workshop on Wireless Network Testbeds, Experimental Evaluation & Characterization