Obtaining the DVD Interface Pointers

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[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

After the filter graph is built, your application can obtain the pointers it needs to control the DVD Navigator, the Filter Graph Manager, and the video window. The basic steps, with error-checking and other code left out for simplicity, are illustrated in the following code example. The complete code is found in the DVD Sample application in the CDvdCore::BuildGraph method. (For more information, see DirectShow Samples.)

// Create an instance of the DVD Graph Builder object.
HRESULT hr;
hr = CoCreateInstance(CLSID_DvdGraphBuilder,
                          NULL,
                          CLSCTX_INPROC_SERVER,
                          IID_IDvdGraphBuilder,
                          reinterpret_cast<void**>(&m_pIDvdGB));

// Build the DVD filter graph.
AM_DVD_RENDERSTATUS buildStatus;
hr = m_pIDvdGB->RenderDvdVideoVolume(pszwDiscPath, m_dwRenderFlags, &buildStatus);

// Get the pointers to the DVD Navigator interfaces.
hr = m_pIDvdGB->GetDvdInterface(IID_IDvdInfo2, reinterpret_cast<void**>(&m_pIDvdI2));
hr = m_pIDvdGB->GetDvdInterface(IID_IDvdControl2, reinterpret_cast<void**>(&m_pIDvdC2));
   ...    
// Get a pointer to the filter graph manager.
hr = m_pDvdGB->GetFiltergraph(&m_pGraph);
...   
// Use the graph pointer to get a pointer to IMediaControl,
// for controlling the filter graph as a whole.
hr = m_pGraph->QueryInterface(IID_IMediaControl, reinterpret_cast<void**>(&m_pIMC));
...   
// Get a pointer to IMediaEventEx,
// used for handling DVD and other filter graph events.
hr = m_pGraph->QueryInterface(IID_IMediaEventEx, reinterpret_cast<void**>(&m_pME)); 
...                
// Use the graph builder pointer again to get the IVideoWindow interface,
// to set the window style and message-handling behavior of the video renderer filter.
hr = m_pIDvdGB->GetDvdInterface(IID_IVideoWindow, reinterpret_cast<void**>(&m_pIVW));
  
hr = m_pDvdGB->GetDvdInterface(IID_IAMLine21Decoder, reinterpret_cast<void**>(&pL21Dec));

DVD Applications