在信号处理中，通常需要收集真实的

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在信号处理中，通常需要把采集信号的实时波形显示出来。 如果直接在屏幕上动态绘图的话，会出现闪烁现象，为了克服这个问题，本文采用的就是先在内存绘图，然后再拷贝到屏幕，从而实现动态绘图而不闪烁。-In signal processing, usually need to collect real-time waveform signal is displayed. If the direct dynamic graphics on the screen, then there will be blinking phenomenon, in order to overcome this problem, this paper is the first graphics memory, and then copied to the screen in order to achieve dynamic graphics without blinking.