摘要
基于高速数字信号处理器(DSP)和大规模现场可编程门阵列(FPGA),成功地研制了小型化、低功耗的实时视频采集、处理和显示平台.其中的DSP负责图像处理,其外围的全部数字逻辑功能都集成在一片FPGA内,包括高速视频流FIFO、同步时序产生与控制、接口逻辑转换和对视频编/解码器进行设置的I2C控制核等.通过增大FIFO位宽、提高传输带宽,降低了占用EMIF总线的时间;利用数字延迟锁相环逻辑,提高了显示接口时序控制精度.系统软件由驱动层、管理层和应用层组成,使得硬件管理与算法程序设计彼此分离,并能协同工作.系统中的图像缓冲区采用了三帧的配置方案,使得该平台最终具有对PAL/NTSC两种制式的全分辨率彩色复合视频信号进行实时采集、显示和处理的能力.
Based on high speed DSP and large scale FPGA, a video capture, processing and display system was developed, which is of miniaturization and low power. In this system, DSP processes images and FPGA implements high speed FIFOs, I^2 C controller core, synchronization timing generation, interface logic conversion, and so on. By extending the bits of FIFO data ports the transfer bandwidth was increased and the time of occupying EMIF bus was reduced. By the digital delay-locked loop （DLL） the timing precision of the display interface was improved. The software of the system is composed of three levels, i.e. driver, management and application, whose benefits are that the design tasks of hardware drivers and arithmetic applications can be separated, and can cooperate with each other. A triple buffering scheme was used for the capture and display, so that the application can always get a new buffer without waiting. It is shown that, this platform is capable of capturing, displaying and processing the full resolution color composite video of PAL/NTSC real time.
