| 该程序可以用于两个人在LAN/Intranet(或者Internet)上进行视频会议。现在有许多视频会议程序，每个都有各自的性能提升技术。主要的问题是视频会议视频帧的尺寸对于传输来说太大。因此，性能依赖于对帧的编解码。我使用快速h263编码库来达到更好的压缩率提高速度。该程序做些小改动也可以在Internet上使用。
音频的录制与播放
我在以前的语音会议程序中使用了RecordSound和PlaySound类，这里我将提供摘要说明RecordSound和PlaySound类的使用。
// Create and Start Recorder Thread
record=new RecordSound(this);
record->CreateThread();
// Create and Start Player Thread
play=new PlaySound1(this);
play->CreateThread();
// Start Recording
record->PostThreadMessage(WM_RECORDSOUND_STARTRECORDING,0,0);
// Start Playing
play->PostThreadMessage(WM_PLAYSOUND_STARTPLAYING,0,0);
// During audio recording, data will be available in the OnSoundData
// callback function of the RecordSound class. Here, you can place
// your code to send the data to remote host...
// To play the data received from the remote host
play->PostThreadMessage(WM_PLAYSOUND_PLAYBLOCK,size,(LPARAM)data);
// Stop Recording
record->PostThreadMessage(WM_RECORDSOUND_STOPRECORDING,0,0);
// Stop Playing
play->PostThreadMessage(WM_PLAYSOUND_STOPPLAYING,0,0);
// At last, to Stop the Recording Thread
record->PostThreadMessage(WM_RECORDSOUND_ENDTHREAD,0,0);
// To stop playing thread...
play->PostThreadMessage(WM_PLAYSOUND_ENDTHREAD,0,0);
视频捕获
使用VFW(Video For Windows)API进行视频捕获，它提供了通过webcam进行视频捕获。VideoCapture.h 和VideoCapture.cpp包含了处理视频捕获的代码。
如下代码说明了如何使用该类：
// Create instance of Class vidcap=new VideoCapture();
// This is later used to call display function of the main// dialog class when the frame is captured... vidcap->SetDialog(this);
// This does lot of work, including connecting to the driver// and setting the desired video format. Returns TRUE if// successfully connected to videocapture device. vidcap->Initialize();
// If successfully connected, you can get the BITMAPINFO// structure associated with the video format. This is later// used to display the captured frame... this->m_bmpinfo=&vidcap->m_bmpinfo;
// Now you can start the capture.... vidcap->StartCapture();
// Once capture is started, frames will arrive in the "OnCaptureVideo"// callback function of the VideoCapture class. Here you call the// display function to display the frame.
// To stop the capture vidcap->StopCapture();
// If your job is over....just destroy it.. vidcap->Destroy();
要使以上代码通过编译，你应该链接适当的库：
#pragma comment(lib,"vfw32")
#pragma comment(lib,"winmm")
显示捕获的视频帧
有许多方法和API可以显示捕获的视频。你可以使用SetDIBitsToDevice()方法直接显示，但给予GDI的函数非常的慢。更好的方法是使用DrawDib API 显示。DrawDib函数为设备无关位图(DIBs)提供了高性能的图形绘制能力。DrawDib函数直接写入视频内存，因此性能更好。
以下代码摘要演示了使用DrawDib API显示视频帧。
// Initialize DIB for drawing... HDRAWDIB hdib=::DrawDibOpen();
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