DirectShow实现的虚拟驱动，该代码采集屏幕作为输入源。-DirectShow realize the virtual drive.

window下注册一个虚拟摄像头，并且在内存中开辟一块共享内存，将共享内存中的数据显示在摄像头中。qq等聊天工具可用。-Window registered a virtual camera, and in memory to open a shared memory, the shared memory data display in the camera. QQ chat tools available.