Applications of Psychovisual Modulation Technology
Current display technologies have achieved high refresh rates and resolutions. However, spatial and temporal discrimination abilities of human eyes are limited. Some displays have spatial or temporal resolutions that are beyond the spatial and temporal discrimination thresholds of human visual systems (HVS). Those displays have psychovisual redundancy in spatial or temporal domains, thus extra capacity in the displays can be used. Psychovisual modulation exploits spatial and temporal redundancies of modern displays. There are mainly two ways to utilize the extra capacity. First, the psychovisual redundancy of display device can be used to generate multiple visual percepts for different viewers. Second, the redundancy can be used for data transmission to computing devices (i.e., visible light communication from display devices to computing devices). Thus, a unidirectional communication channel from display device to computing device can be widely used in many fields.
Fig. 1. Snapshot of information security display system. First row, the original information frames. Second row, the glass-free views of the blank screen. Third row, direct comparison of glass/glass-free views. The first to fifth columns gives the results for applications of an image viewer, ebook reader, PDF reader, video player, and random area hiding, respectively.
Fig. 2. Results of the dual-view medical image visualization system. (a) and (d) show two pair of T1 and T2 weighted MRI images. (b) and (e) T1 weighted images viewed through the upper part of the glasses. (c) and (f) T2 weighted images viewed through the lower part of the glasses.
Fig. 3. Two example applications of the proposed invisible QR codes. (a) The user views images without perceiving the invisible QR codes. (b) Smartphones detect and recolonize the invisible QR codes. (c) Smartphones open the links stored in the invisible QR codes. In the first row, the user scans a dress (Elsa’s dress in the movie of Frozen 2013) on the screen and the smartphone detect the invisible QR code that links to an online store. In the second row, the user scans a person (Agnes Gru in the movie of Despicable Me 2010) about who he wants to get more information and the invisible QR code links to the corresponding Wikipedia page.
FIg. 4. Working mechanism of camcorder piracy tracking by temporal psychovisual modulation (TPVM) display technology.