graph.cpp

非常有用的VC视频音频开发所需要的东西 需要有用

//------------------------------------------------------------------------------
// File: Graph.cpp
//
// Desc: Sample code for BDA graph building.
//
// Copyright (c) 2000-2002, Microsoft Corporation. All rights reserved.
//------------------------------------------------------------------------------

#include "graph.h"


// 
// NOTE: In this sample, text strings are hard-coded for 
// simplicity and for readability.  For product code, you should
// use string tables and LoadString().
//

//
// An application can advertise the existence of its filter graph
// by registering the graph with a global Running Object Table (ROT).
// The GraphEdit application can detect and remotely view the running
// filter graph, allowing you to 'spy' on the graph with GraphEdit.
//
// To enable registration in this sample, define REGISTER_FILTERGRAPH.
//
#define REGISTER_FILTERGRAPH

// We use channel 46 internally for testing.  Change this constant to any value.
#define DEFAULT_PHYSICAL_CHANNEL    46L


// Constructor, initializes member variables
// and calls InitializeGraphBuilder
CBDAFilterGraph::CBDAFilterGraph() :
    m_fGraphBuilt(FALSE),
    m_fGraphRunning(FALSE),
    m_NetworkType(ATSC),
    m_lMajorChannel(-1), 
    m_lMinorChannel(-1),
    m_lPhysicalChannel(DEFAULT_PHYSICAL_CHANNEL),
    m_dwGraphRegister (0)
{
    if(FAILED(InitializeGraphBuilder()))
        m_fGraphFailure = TRUE;
    else
        m_fGraphFailure = FALSE;
}


// Destructor
CBDAFilterGraph::~CBDAFilterGraph()
{
    if(m_fGraphRunning)
    {
        StopGraph();
    }

    if(m_fGraphBuilt || m_fGraphFailure)
    {
        TearDownGraph();
    }
}


// Instantiate graph object for filter graph building
HRESULT
CBDAFilterGraph::InitializeGraphBuilder()
{
    HRESULT hr = S_OK;
    
    // we have a graph already
    if (m_pFilterGraph)
        return S_OK;

    // create the filter graph
    if (FAILED (hr = m_pFilterGraph.CoCreateInstance (CLSID_FilterGraph)))
    {
        ErrorMessageBox(TEXT("Couldn't CoCreate IGraphBuilder\n"));
        m_fGraphFailure = true;
        return hr;
    }
    
    return hr;
}


// BuildGraph sets up devices, adds and connects filters
HRESULT
CBDAFilterGraph::BuildGraph(NETWORK_TYPE NetType)
{
    HRESULT hr = S_OK;
    m_NetworkType = NetType;

    // if we have already have a filter graph, tear it down
    if(m_fGraphBuilt)
    {
        if(m_fGraphRunning)
        {
            hr = StopGraph ();
        }

        hr = TearDownGraph ();
    }

    // STEP 1: load network provider first so that it can configure other
    // filters, such as configuring the demux to sprout output pins.
    // We also need to submit a tune request to the Network Provider so it will
    // tune to a channel
    if(FAILED (hr = LoadNetworkProvider()))
    {
        ErrorMessageBox(TEXT("Cannot load network provider\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    hr = m_pNetworkProvider->QueryInterface(__uuidof (ITuner), reinterpret_cast <void**> (&m_pITuner));
    if(FAILED (hr))
    {
        ErrorMessageBox(TEXT("pNetworkProvider->QI: Can't QI for ITuner.\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    // create a tune request to initialize the network provider
    // before connecting other filters
    CComPtr <IATSCChannelTuneRequest>  pATSCTuneRequest;
    if(FAILED (hr = CreateATSCTuneRequest(
                                        m_lPhysicalChannel,
                                        m_lMajorChannel, 
                                        m_lMinorChannel,
                                        &pATSCTuneRequest
                                        )))
    {
        ErrorMessageBox(TEXT("Cannot create tune request\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    //submit the tune request to the network provider
    hr = m_pITuner->put_TuneRequest(pATSCTuneRequest);
    if(FAILED(hr))
    {
        ErrorMessageBox(TEXT("Cannot submit the tune request\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }


    // STEP2: Load tuner device and connect to network provider
    if(FAILED (hr = LoadFilter (
                                KSCATEGORY_BDA_NETWORK_TUNER, 
                                &m_pTunerDevice,
                                m_pNetworkProvider, 
                                TRUE
                                )))
    {
        ErrorMessageBox(TEXT("Cannot load tuner device and connect network provider\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    // STEP3: Load tuner device and connect to demodulator device
    if(FAILED (hr = LoadFilter (
                                KSCATEGORY_BDA_RECEIVER_COMPONENT, 
                                &m_pDemodulatorDevice,
                                m_pTunerDevice, 
                                TRUE
                                )))
    {
        ErrorMessageBox(TEXT("Cannot load capture device and connect tuner\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    // Step4: Load capture device and connect to tuner device
    if(FAILED (hr = LoadFilter (
                                KSCATEGORY_BDA_RECEIVER_COMPONENT, 
                                &m_pCaptureDevice,
                                m_pDemodulatorDevice, 
                                TRUE
                                )))
    {
        ErrorMessageBox(TEXT("Cannot load capture device and connect tuner\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    // Step5: Load demux
    if(FAILED (hr = LoadDemux()))
    {
        ErrorMessageBox(TEXT("Cannot load demux\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    //
    // this next call loads and connects filters associated with
    // the demultiplexor. if you want to manually load individual
    // filters such as audio and video decoders, use the code at
    // the bottom of this file
    //
#ifdef REGISTER_FILTERGRAPH
    hr = AddGraphToRot (m_pFilterGraph, &m_dwGraphRegister);
    if (FAILED(hr))
    {
        ///ErrorMessageBox(TEXT("Failed to register filter graph with ROT!  hr=0x%x"), hr);
        m_dwGraphRegister = 0;
    }
#endif

    // Step6: Render demux pins
    if(FAILED (hr = RenderDemux()))
    {
        ErrorMessageBox(TEXT("Cannot load demux\n"));
        TearDownGraph();
        m_fGraphFailure = true;
        return hr;
    }

    m_fGraphBuilt = true;
    m_fGraphFailure = false;
    
    return S_OK;
}


// Loads the correct tuning space based on NETWORK_TYPE that got
// passed into BuildGraph()
HRESULT
CBDAFilterGraph::LoadTuningSpace()
{   
    CComPtr <ITuningSpaceContainer>  pITuningSpaceContainer;

    // get the tuningspace container for all the tuning spaces from SYSTEM_TUNING_SPACES
    HRESULT hr = pITuningSpaceContainer.CoCreateInstance(CLSID_SystemTuningSpaces);
    if (FAILED (hr))
    {
        ErrorMessageBox(TEXT("Could not CoCreate SystemTuningSpaces\n"));
        return hr;
    }

    CComVariant var (m_NetworkType);

    hr = pITuningSpaceContainer->get_Item(var, &m_pITuningSpace);

    if(FAILED(hr))
    {
        ErrorMessageBox(TEXT("Unable to retrieve Tuning Space\n"));
    }

    return hr;
}


// Creates an ATSC Tune Request
HRESULT
CBDAFilterGraph::CreateATSCTuneRequest(
        LONG lPhysicalChannel,
        LONG lMajorChannel, 
        LONG lMinorChannel,
        IATSCChannelTuneRequest**   pTuneRequest
    )
{
    HRESULT hr = S_OK;

    if (pTuneRequest == NULL)
    {
        ErrorMessageBox (TEXT("Invalid pointer\n"));
        return E_POINTER;
    }

    // Making sure we have a valid tuning space
    if (m_pITuningSpace == NULL)
    {
        ErrorMessageBox(TEXT("Tuning Space is NULL\n"));
        return E_FAIL;
    }

    //  Create an instance of the ATSC tuning space
    CComQIPtr <IATSCTuningSpace> pATSCTuningSpace (m_pITuningSpace);
    if (!pATSCTuningSpace)
    {
        ErrorMessageBox(TEXT("Cannot QI for an IATSCTuningSpace\n"));
        return E_FAIL;
    }

    //  Create an empty tune request.
    CComPtr <ITuneRequest> pNewTuneRequest;
    hr = pATSCTuningSpace->CreateTuneRequest(&pNewTuneRequest);

    if (FAILED (hr))
    {
        ErrorMessageBox(TEXT("CreateTuneRequest: Can't create tune request.\n"));
        return hr;
    }

    //query for an IATSCChannelTuneRequest interface pointer
    CComQIPtr <IATSCChannelTuneRequest> pATSCTuneRequest (pNewTuneRequest);
    if (!pATSCTuneRequest)
    {
        ErrorMessageBox(TEXT("CreateATSCTuneRequest: Can't QI for IATSCChannelTuneRequest.\n"));
        return E_FAIL;
    }

    //  Set the initial major and minor channels
    hr = pATSCTuneRequest->put_Channel(lMajorChannel);
    if(FAILED(hr))
    {
        ErrorMessageBox(TEXT("put_Channel failed\n"));
        return hr;
    }

    hr = pATSCTuneRequest->put_MinorChannel(lMinorChannel);
    if(FAILED(hr))
    {
        ErrorMessageBox(TEXT("put_MinorChannel failed\n"));
        return hr;
    }

    CComPtr <IATSCLocator> pATSCLocator;
    hr = pATSCLocator.CoCreateInstance (CLSID_ATSCLocator);
    if (FAILED( hr))
    {
        ErrorMessageBox(TEXT("Cannot create the ATSC locator failed\n"));
        return hr;
    }

    //  Set the initial physical channel.
    //
    hr = pATSCLocator->put_PhysicalChannel (lPhysicalChannel);
    if (FAILED( hr))
    {
        ErrorMessageBox(TEXT("Cannot put the physical channel\n"));
        return hr;
    }

    hr = pATSCTuneRequest->put_Locator (pATSCLocator);
    if (FAILED (hr))
    {
        ErrorMessageBox(TEXT("Cannot put the locator\n"));
        return hr;
    }

    hr = pATSCTuneRequest.QueryInterface (pTuneRequest);

    return hr;
}


// LoadNetworkProvider loads network provider
HRESULT
CBDAFilterGraph::LoadNetworkProvider()
{
    HRESULT     hr = S_OK;
    CComBSTR    bstrNetworkType;
    CLSID       CLSIDNetworkType;

    // obtain tuning space then load network provider
    if(m_pITuningSpace == NULL)
    {
        hr = LoadTuningSpace();
        if(FAILED(hr))
        {
            ErrorMessageBox(TEXT("Cannot load TuningSpace\n"));
            return hr;
        }
    }

    // Get the current Network Type clsid
    hr = m_pITuningSpace->get_NetworkType(&bstrNetworkType);
    if (FAILED (hr))
    {
        ErrorMessageBox(TEXT("ITuningSpace::Get Network Type failed\n"));
        return hr;
    }

    hr = CLSIDFromString(bstrNetworkType, &CLSIDNetworkType);
    if (FAILED (hr))
    {
        ErrorMessageBox(TEXT("Couldn't get CLSIDFromString\n"));
        return hr;
    }

    // create the network provider based on the clsid obtained from the tuning space
    hr = CoCreateInstance(CLSIDNetworkType, NULL, CLSCTX_INPROC_SERVER,
                          IID_IBaseFilter, 
                          reinterpret_cast<void**>(&m_pNetworkProvider));
    if (FAILED (hr))
    {
        ErrorMessageBox(TEXT("Couldn't CoCreate Network Provider\n"));
        return hr;
    }

    //add the Network Provider filter to the graph
    hr = m_pFilterGraph->AddFilter(m_pNetworkProvider, L"Network Provider");

    return hr;
}


// enumerates through registered filters
// instantiates the the filter object and adds it to the graph
// it checks to see if it connects to upstream filter
// if not,  on to the next enumerated filter
// used for tuner, capture, MPE Data Filters and decoders that
// could have more than one filter object
// if pUpstreamFilter is NULL don't bother connecting
HRESULT