directshow摄像头录像代码

 HRESULT Cvp::RecordPlay(CString szFile)
{
 if(isStop!=m_status) Stop();
 HRESULT hr;
 CHECK_ERROR( GetInterfaces(),"GetInterfaces failed." );
 CHECK_ERROR( CoCreateInstance (CLSID_CaptureGraphBuilder2 , NULL, CLSCTX_INPROC,
  IID_ICaptureGraphBuilder2, (void **) &m_pC) ,"CoCreateInstan ICaptureGraphBuilder2 failed:");
 CHECK_ERROR( m_pC->SetFiltergraph(m_pG),"Failed to set capture filter graph.");
 
 hr = FindCaptureDevice(&m_pBF);
    if (FAILED(hr))
      return hr;
   
 if(m_pBF) hr=m_pG->AddFilter(m_pBF,L"Video Capture");
 if(hr!=NOERROR)
 {
  MessageBox(m_hWnd,"Cannot add vidcap to filtergraph./r/n/r/n"
        "If you have a working video capture device, please make sure/r/n"
        "that it is connected and is not being used by another application./r/n"
        "The application will now close.","Error",MB_OK);
  return hr;
 }

 IBaseFilter* pASFWriter = 0;
 CHECK_ERROR( m_pC->SetOutputFileName(&MEDIASUBTYPE_Avi,CA2W(szFile),&pASFWriter,NULL),"Failed to setOutputFile");
 //connect source filter with render filter
  CHECK_ERROR( m_pC->RenderStream (&PIN_CATEGORY_PREVIEW, &MEDIATYPE_Video,m_pBF, NULL, NULL),
               "Couldn't render the video capture stream./r/n"
               "The capture device may already be in use by another application./r/n"
               "The sample will now close.");
    CHECK_ERROR( m_pC->RenderStream (&PIN_CATEGORY_CAPTURE, &MEDIATYPE_Video,m_pBF, NULL, pASFWriter),
               "Couldn't render the video capture stream./r/n"
               "The capture device may already be in use by another application./r/n"
               "The sample will now close.");
 
 HELPER_RELEASE(m_pBF);
 DisplayVideoWin();
 CHECK_ERROR(m_pM->Run(),"Failed to run:");
 m_status=isRecord;
 return hr;
}