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GMFBridge usage in DirectShow


enter code hereI have to stop and start Video Renderer Filter dynamically . That is not possible with "normal" Direct Show Architecture without creating new graph. But with GMFBridge it seems it is possible.

But i can not figure out how to use it.( yes i read the paper at http://www.gdcl.co.uk/gmfbridge/index.htm )

My Graph is:

SourceFilter ---> MyCustomTransformFilter ---> Video Rendrer Filter

So GMFBridge fits where?

i) I can devide my graph two pieces 
       [ Source Filter + MyCustomFilter ] + Video Rendere


ii) Then how to add my filters to graph, and stop start Video Rendrere without 
affecting the rest of my grapg using GMFBridge?

Update:

Thanks Wimmel

I just confused... Let me clear what i understand

i) I have single graph at first

 (SingleGraph) SourceFilter ---> MyCustomTransformFilter ---> Video Rendrer Filter

ii) In order to use GMFBridge i divede my single graph into two separate graph

 First Graph  :  SourceFilter ---> MyCustomTransformFilter --> GMFBridgeSinkFilter
 Second Graph :  GMFBridgeSourceFilter ---> Video Renderer Filter

Well, GMFBridgeSinkFilter and GMFBridgeSourceFilter ? what are they? their class type?

iii) Then i create an intance of IGMFBridgeControllerPtr and make necessary init...

IGMFBridgeControllerPtr bridgeController = ......

.....
bridgeController->AddStream(true, eUncompressed, true); 
bridgeController->AddStream(false, eUncompressed, true); 

iv) Bridge Controller add a sink filter to the source graph and connect it:

 bridgeController->InsertSinkFilter(sourceGraph, sourceGraphSinkFilter);

What are sourceGraph, sourceGraphSinkFilter s ?

// now connect it like this:
// SourceFilter ---> MyCustomTransformFilter ---> SourceGraphSinkFilter

You mean programtically connect those filters in the source graph?

iv) In the second graph let the controller add a source filter, and connect it to the renderer:

bridgeController->InsertSourceFilter(sinkFilter, renderGraph, renderGraphSourceFilter);

Again what are sinkFilter,renderGraphSourceFilter etc?

 // now connect it like this:
 // RenderGraphSourceFilter ---> Video Renderer Filter

And You mean programtically connect those filters in the source graph?


Solution

  • You probably want to create the following two graphs:

    1: SourceFilter ---> MyCustomTransformFilter ---> GMFBridgeSinkFilter
    
    2: GMFBridgeSourceFilter ---> Video Renderer Filter
    

    Basically you do the following:

    Create a GMFBridgeController and configure it, for example one video and one audio stream:

    IGMFBridgeControllerPtr  m_pController; 
    HRESULT hr = m_pController.CreateInstance(__uuidof(GMFBridgeController)); 
    m_pController->AddStream(true, eUncompressed, true); 
    m_pController->AddStream(false, eUncompressed, true); 
    

    Now let the controller add a sink filter to the source graph and connect it:

    hr = m_pController->InsertSinkFilter(m_pSourceGraph, &m_pSourceGraphSinkFilter);
    // now connect it like this:
    // SourceFilter ---> MyCustomTransformFilter ---> SourceGraphSinkFilter
    

    In your second graph let the controller add a source filter, and connect it to the renderer:

    hr = m_pController->InsertSourceFilter(m_pSourceGraphSinkFilter, m_pRenderGraph, &m_pRenderGraphSourceFilter); 
    // now connect it like this:
    // RenderGraphSourceFilter ---> Video Renderer Filter
    

    Start both graphs and connect them:

    hr = m_pController->BridgeGraphs(m_pSourceGraphSinkFilter, m_pRenderGraphSourceFilter); 
    

    If you want to stop one graph, first disconnect:

    m_pController->BridgeGraphs(NULL, NULL);
    

    edit

    Here are some clarifications you asked for:

    GMFBridgeSinkFilter and GMFBridgeSourceFilter are the filters created by GMFBridge. I don't know their exact types, but at least they derive from IBaseFilter.

    m_pSourceGraph and m_pRenderGraph are the IGraphBuilder interfaces of both graphs you have created.

    m_pSourceGraphSinkFilter and m_pRenderGraphSourceFilter are pointers to IBaseFilter to receive the pointer to the filter created by GMFBridge.

    And yes, when I say connect filters, I mean programtically connect them. As far as I know you cannot test GMFBridge in graphedit.