# Experimental Evaluation of Display Field Communication Based on Machine Learning and Modern Design
## 2 Related Works  
The D2C communication approaches primarily focus on embedding the data in the spatial domain of an image. For instance, [1] proposed a novel screen-to-camera image coding scheme dubbed as TERA. In particular, a new color decomposition-based encoding scheme was designed that encodes the information into a single host frame by creating two complementary frames. The work in [2] introduced an optical covert channel in which attackers can leak sensitive information from air-gapped computers through manipulations on the screen brightness. Malware on a compromised computer can obtain sensitive data and modulate them within the screen brightness, invisible to users. The small changes in brightness are invisible to humans but can be recovered from a video stream taken by a camera such as a local security camera, smartphone camera, or webcam. More recently, the work in [3] proposed embedding 2D barcodes in the blue channel of an image frame to decrease the obtrusiveness. Reference [19] encoded the data in varying pixel translucency of the image frames. Reference [20] presented a demo of imperceptible video communication that takes advantage of both off-the-shelf cameras and LCDs, and transfers data over a normal video without reliance on additional infrastructure. In another work [21], InFrame is proposed that enables dual-mode full-frame communication for both humans and devices simultaneously. It leverages the temporal flick-fusion property of the human visual system and the fast frame rate of modern displays. InFrame multiplexes data onto full-frame video contents through a novel complementary frame design and thus ensures screen-to-camera data communication without affecting the primary video-viewing experience for human users. The effect of vignetting on pixelated multiple-input multiple-output (MIMO) optical wireless communication system was analyzed in [22], which shows that vignetting causes attenuation and intercarrier interference in the spatial frequency domain. Moreover, it proposed error correction schemes to verify and recover the lost blocks and frames during D2C communications. Similarly, the authors of [23] proposed a novel approach to embed hyperlinks into common images, making the hyperlinks invisible to human eyes but detectable for mobile devices equipped with a camera. The work in [24] evaluated the performance of the LCD-to-camera link, where the LCD modulates ambient light by changing its level of transparency. The authors claimed their prototype to be the first screen-to-camera system that works solely with ambient light. DeepLight [25] introduced a novel, holistic approach for robust screen-to-camera communication that incorporates ML models in the decoding pipeline to achieve humanly imperceptible, moderately high communication rates under diverse real-world conditions. On the other hand, the work in [26] presented a hidden screen-to-camera communication system built upon invisible visual and inaudible audio dual channels. It takes the complementary advantages of video and audio channels by exploiting the reliable yet low-rate inaudible audio link as the control channel while the unreliable but high-rate visual link as the data channel. [PERSON] [27] proposed MobiScan, a dynamic and invisible screen-to-camera communication system that can ensure data security, real-time communication, and flexible capture angle. Similarly, the authors of [28] presented DisCo, a novel display-camera communication system, which enables displays and cameras to communicate with each other while also displaying and capturing images for human consumption. Messages are transmitted by temporally modulating the display brightness at high frequencies so that they are imperceptible to humans. Messages are received by a rolling shutter camera that converts the temporally modulated incident light into a spatial flicker pattern. In the captured image, the flicker pattern is superimposed on the pattern shown on the display.