一种外置式视频同步信号发生器的设计

对随机视频信号的特点进行了研究，提出了采用谱分析提取随机视频信号的同步频率的方法，根据数据传输的要求设计了基于USB接口的外置式视频同步信号发生器并给出了系统的硬件框图和软件流程。系统具有自动分析随机视频信息隐含的同步信号频率，精确产生同步脉冲信号的特点，满足随机视频信号采集和稳定显示的同步要求。同步精度达到300帧内图像漂移小于1个像素。利用该视频同步信号发生器控制非标准图像采集卡实现了计算机辐射的随机视频信号的采集和稳定显示。

Design of External Generator of Video Synchronous Signals

On the base of stochastic video information, the method of using spectral analysis to extract the synchronous frequency of stochastic video information was presented. An external generator video synchronous signal based on USB interface was designed according to the requirement of data transmission. The block diagram of system's hardware and software step were given. Automatic analysis of the synchronous frequency hid in stochastic video information and the accurate generation of synchronous impulse signal were the important features of this system. The system meets the requirement of acquisition and stable display of stochastic video information, the image excursion was less than one pixel within 300 frames. Using this generator of video synchronous signals to control an image capture card, the acquisition and steady display of the stochastic video information radiated from computer were achieved.