Electromagnetic radiation of computer contains video information which causes the information leakage. Electromagnetic radiation of PC contains video information, and the image can be reconstructed. In this paper, the way of computer video information transmission of DVI video interface be analyzed. The model of time and frequency domain corresponding to serial transmission and parallel transmission of video information is built. According to the principle of video information interception and reconstruction, the radiation leakage characteristics when different video signal is transmitted through the serial and parallel way is researched in this paper. Through the analysis and measurement of the electromagnetic information leakage, then we can get a conclusion that it is easy to be intercepted when the gray image is transmitted in serial way, black and white image is transmitted in parallel way, because it shows the characteristic of 'false parallel and real serial'. 2016 IEEE.