Research And Realization Of Device For Multi-Channel Video Encoding

Video monitoring system has been widely used in the fields of scientific research, security control, intelligent traffic system, flying target tracking, etc. and it plays an important role in national economy and national defense construction. Most of video monitoring systems on the market are composed of industrial computer and video image data acquiring card and they work unstably, and are unsuitable for unmanned transformer substation. This thesis comprehensively compares several compression schemes which break away from PC. On the basis of this, an embedded multi-channel video monitoring system is designed based on digital signal processor (DSP). The system regards TMS320C6211 of TI as core processor and accomplishes digital acquisition and compression for analog video signal through high-speed decoding circuit.This paper introduces overall design thoughts of the system and concrete software and hardware design work in detail and discusses several main problems of overall design of the system such as signal integrality, I2C BUS control means and video signal acquiring means, etc. Because the compression module based on TMS320C6211 is a high-speed circuit board, so the design procedure and rules of the PCB are described in detail. On this basis, the problem of signal integrality is found and solved by systematic analysis and software emulation before routing. Because the control interface of video decoding chip in the system is I2C bus, so according to concrete conditions of DSP chip, the hardware interface of DSP simulating I2C bus timing is designed and the I2C bus communication program is worked out to adapt the system to accomplish configuration and communication of the video decoding chip. According to the characteristics of video signal that the system processed, this thesis adopts interrupt management method by using FIFO and digital video signals are collected and saved through EDMA controller of C6211. Based on this, software layer model of the whole video compression system is designed and bottom layer software module of the system is worked out to offer soft interrupt interface for the program.