Research And Design Of Digital HD Video Key Control System Based On FPGA

With the continuous development of electronic science and technology, high definition television (HDTV) has been widely applied because of its high quality video and audio. In the television broadcast system, video keying technology provided supports to diversity enhancement of digital television broadcast. Due to advantages including the less difficulty of developing digitizing system, strong system stability and low price, traditional analog video keying devices will also be transformed into digital devices. Therefore, this paper conducts research and design on digital high definition video keying systems based on FPGA.The digital high definition video keying control system designed in this paper is based on Xilinx’s FPGA chip XC6SLX75TFGG676of Spartan6series. This system includes two modules:the reception and transmission modules of HD-SDI signals, synthesis module of multi-channel video linear keying control. The double keying control synthesis scheme of the main program video signals and two-channel logo video signal is presented in this paper, which is the reasonable solution to the problem of high-definition display of multiple logo; The problem of video distortion caused by single hardware is avoided by adopting linear keying control scheme when video is broadcasted; at the same time the reception and transmission of HD-SDI signal is implemented through Xilinx’s high-speed transceiver ports to avoid the quantity and complexity of PCB designing work using specific chips while the development costs of the system can be greatly reduced. Hardware system based on the the main processing core of FPGA is designed, which includes FPGA circuit, GS2984cable equalization circuit, high-speed transceiver interface circuit, configure and test circuit, GS2989output driver circuits and power supply circuits. And signal integrity of PCB designing is analyzed and tested with Hyperlynx8.2software system. The system’s software designing is achieved by Xilinx’s FPGA design platform ISE13.1mainly containing high-speed transceiver port hardcore GTP, pixel adjustment, video double keying synthesis, and the keying control synthesis of multi-channel logo and main program video is implemented through testing system.The research and design shows that high-definition video keying system designed in this thesis achieves the aim at synthesizing the foreign multi-channel video and the main program video, after synthesized by keying system, the video become much more smooth and clear. The keying system design in this thesis is suitable for multi-channel video synthesis under different circumstances and has low designing cost for large-scale promoting. And it is of high practical value in the studio.