Each camera on digital devices is made of hundreds of thousands of sensors, with which it can separate and capture the light from spatial points in a fine-grain manner, enabling high-rate data transfer from the digital display to the camera, i.e. screen-camera communication. Compared with RF (Radio Frequency) technologies, visible light approaches are more convenient and secure.

In this work, we design a mobile-to-mobile screen-camera communication system to handle the rolling shutter issue and increase the reliability. First, a time-domain self-restoration coding scheme is proposed to identify mixed frames for doubling the coding efficiency. Second, we design a feedback channel for reliability. It is further integrated with an adaptive scheme to achieve robustness in challenging conditions. We implement the system prototype on the Android platform and conduct extensive experiments. The results show that our system increases the throughput by an order-of-magnitude (16x) compared with existing rolling-shutter solutions and two times (1.8x) over the color-barcode system.