DVBT DirectShow编程收不到信号？？

watchsea

我DirectShow开发DVBT的应用程序。
DVBT接收卡代号：USB 2870 Devie
信号源是用模拟的信号源来代替。
用NewSoft 的PVR软件可以收到音视频信号，至少也可以扫描到频道，但用自己写的代码，却扫描不到信号，不知道为什么。现把代码帖出来，请高手指点迷津。
//这是构建Filter Graph的函数,有些支节的代码删去
HRESULT VVPreviewBuilderDVBT()
{
    HRESULT hr = S_OK;
    if (m_pGraph == NULL)
    {
        return E_FAIL;
    }
    hr = m_pBuild.CoCreateInstance(CLSID_CaptureGraphBuilder2, 0, CLSCTX_INPROC_SERVER);
    hr = m_pBuild->SetFiltergraph(m_pGraph);
    // 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("DVB-T")))
    {
        TearDownGraph();
        return hr;
    }
    hr = m_pNetworkProvider->QueryInterface(__uuidof (ITuner), reinterpret_cast <void**> (&m_pITuner));
    if(FAILED (hr))
    {
        TearDownGraph();
        return hr;
    }
    // create a tune request to initialize the network provider
    // before connecting other filters
    CComPtr <IDVBTuneRequest> pDVBTTuneRequest;
    if(FAILED (hr = CreateDVBTTuneRequest(&pDVBTTuneRequest)))
    {
        TearDownGraph();
        return hr;
    }
    //submit the tune request to the network provider
    hr = m_pITuner->put_TuneRequest(pDVBTTuneRequest);
    if(FAILED(hr))
    {
        TearDownGraph();
        return hr;
    }
    // STEP2: Load tuner device and connect to network provide
    if(FAILED (hr = LoadFilter (KSCATEGORY_BDA_NETWORK_TUNER,
        &m_pTunerDemodDevice,
        m_pNetworkProvider,
        TRUE)))
    {
        TearDownGraph();
        return hr;
    }
    // Step3: Load capture device and connect to tuner/demod device
    if(FAILED (hr = LoadFilter (KSCATEGORY_BDA_RECEIVER_COMPONENT,
        &m_pVideoDevice,
        m_pTunerDemodDevice,
        TRUE)))
    {
        TearDownGraph();
        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
    // Step4: Load demux
    hr = AddFilterByCLSID2(m_pGraph, CLSID_MPEG2Demultiplexer, L"Mpeg2 Demux",
        &m_pDemux);
    if(FAILED (hr))
    {
        TearDownGraph();
        return hr;
    }

    // Step5: Render demux pins
    //if (FAILED (hr = BuildAVSegment()))
    if(FAILED (hr = RenderDemux()))
    {
        TearDownGraph();
        return hr;
    }
    // Step6: get pointer to Tuner and Demod pins on Tuner/Demod filter
    // for setting the tuner and demod. property sets
    if (GetTunerDemodPropertySetInterfaces() == FALSE )
    {
  TearDownGraph();
    }
    return S_OK;
}


//

HRESULT LoadNetworkProvider( CComBSTR pNetworkType)
{
    HRESULT  hr = S_OK;
    CComBSTR bstrNetworkType;
    CLSID    CLSIDNetworkType;
    OutputDebugString(TEXT("BDASample: CBDAFilterGraph:oadNetworkProvider\n"));
    // obtain tuning space then load network provider
    if(m_pITuningSpace == NULL)
    {
        hr = LoadTuningSpace(pNetworkType);
        if(FAILED(hr))
        {
            OutputDebugString(TEXT("BDASample: Cannot find MYDVBT TuningSpace\n"));
            // so we create one.
            hr = CreateTuningSpace(pNetworkType);
            if (FAILED(hr))
            {
                TearDownGraph();
                return E_FAIL;
            }
        }
    }
    if (!m_pITuningSpace)
    {
        TearDownGraph();
        return E_FAIL;
    }
    // Get the current Network Type clsid
    hr = m_pITuningSpace->get_NetworkType(&bstrNetworkType);
    if (FAILED (hr))
    {
        TearDownGraph();
        return hr;
    }
    hr = CLSIDFromString(bstrNetworkType, &CLSIDNetworkType);
    if (FAILED (hr))
    {
        TearDownGraph();
        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))
    {
        TearDownGraph();
        return hr;
    }
    //add the Network Provider filter to the graph
    hr = m_pGraph->AddFilter(m_pNetworkProvider, L"Network Provider");
    return hr;
}


//LoadFilter (....) 该函数将两个Filter 连接起来，具体代码比较简单，就不把代码巾出来了。



HRESULT  CreateTuningSpace(CComBSTR pNetworkType)
{
    HRESULT hr = S_OK;
    OutputDebugString(TEXT("BDASample: CBDAFilterGraph::CreateTuningSpace\n"));
    CComPtr <IDVBTuningSpace> pIDVBTuningSpace;
    hr = pIDVBTuningSpace.CoCreateInstance(CLSID_DVBTuningSpace);
    if (FAILED(hr) || !pIDVBTuningSpace)
    {
        //ErrorMessageBox(TEXT("Failed to create system tuning space."));
        return FALSE;
    }
    // set the Frequency mapping
    WCHAR szFreqMapping[ 3 ]=L"-1";
    BSTR bstrFreqMapping = SysAllocString(szFreqMapping);
    if (bstrFreqMapping)
    {
        hr = pIDVBTuningSpace->put_FrequencyMapping(bstrFreqMapping); // not used
        SysFreeString(bstrFreqMapping);
    }
    // set the Friendly Name of the network type, shown as Name in the registry
    hr = pIDVBTuningSpace->put_UniqueName(pNetworkType);
    if (FAILED(hr))
    {
        OutputDebugString(TEXT("BDASample: put_FriendlyName failed\n"));
        return hr;
    }
    // set the System type to terrestrial
    hr = pIDVBTuningSpace->put_SystemType(DVB_Terrestrial);
    if (FAILED(hr))
    {
        OutputDebugString(TEXT("BDASample: put_SystemType failed\n"));
        return hr;
    }
    // set the Network Type to DVBT
    CComBSTR clsid_dvbt = ("{216C62DF-6D7F-4e9a-8571-05F14EDB766A}");
    hr = pIDVBTuningSpace->put_NetworkType(clsid_dvbt);
    if (FAILED(hr))
    {
        OutputDebugString(TEXT("BDASample: put_NetworkType failed\n"));
        return hr;
    }
    // set the Friendly Name, shown as Description in the registry
    WCHAR szFriendlyName[ 8 ]=L"UK DVBT";
    BSTR bstrFriendlyName = SysAllocString(szFriendlyName);
    if (bstrFriendlyName)
    {
        hr = pIDVBTuningSpace->put_FriendlyName(bstrFriendlyName);
        SysFreeString(bstrFriendlyName);
    }
    // create DVBT Locator
    CComPtr <IDVBTLocator> pIDVBTLocator;
    hr = CoCreateInstance(CLSID_DVBTLocator,
                            NULL,
                            CLSCTX_INPROC_SERVER,
                            IID_IDVBTLocator,
                            reinterpret_cast<void**>(&pIDVBTLocator));
    if (FAILED(hr) || !pIDVBTLocator)
    {
        // ErrorMessageBox(TEXT("BDASample: Failed to create system locator."));
        return hr;
    }
    // NOTE: The below parameter with the exception of
    //       setting the carrier frequency don't need to set.
    //       Thus they are set to -1.  The demodulator can
    //       handle these parameters without having to specifically
    //       set them in the hardware.
    // set the Carrier Frequency
    hr = pIDVBTLocator->put_CarrierFrequency(m_ulCarrierFrequency);
    // set the Bandwidth
    hr = pIDVBTLocator->put_Bandwidth(-1);                            // not used
    // set the Low Priority FEC type
    hr = pIDVBTLocator->put_LPInnerFEC(BDA_FEC_METHOD_NOT_SET);       // not used
    // set the Low Priority code rate
    hr = pIDVBTLocator->put_LPInnerFECRate(BDA_BCC_RATE_NOT_SET);     // not used
    // set the hieriarcy alpha
    hr = pIDVBTLocator->put_HAlpha(BDA_HALPHA_NOT_SET);               // not used
    // set the guard interval
    hr = pIDVBTLocator->put_Guard(BDA_GUARD_NOT_SET);                 // not used
    // set the transmission mode/FFT
    hr = pIDVBTLocator->put_Mode(BDA_XMIT_MODE_NOT_SET);              // not used
    // set whether the frequency is being used by another DVB-T broadcaster
    hr = pIDVBTLocator->put_OtherFrequencyInUse(VARIANT_BOOL(FALSE)); // not used
    // set the inner FEC type
    hr = pIDVBTLocator->put_InnerFEC(BDA_FEC_METHOD_NOT_SET);         // not used
    // set the inner code rate
    hr = pIDVBTLocator->put_InnerFECRate(BDA_BCC_RATE_NOT_SET);       // not used
    // set the outer FEC type
    hr = pIDVBTLocator->put_OuterFEC(BDA_FEC_METHOD_NOT_SET);         // not used
    // set the outer code rate
    hr = pIDVBTLocator->put_OuterFECRate(BDA_BCC_RATE_NOT_SET);       // not used
    // set the modulation type
    hr = pIDVBTLocator->put_Modulation(BDA_MOD_NOT_SET);              // not used
    // set the symbol rate
    hr = pIDVBTLocator->put_SymbolRate(-1);                           // not used
    // set this a default locator
    hr = pIDVBTuningSpace->put_DefaultLocator(pIDVBTLocator);
    // create a tuning space container for the values we just set
    // so we can create in the registry.
    CComPtr <ITuningSpaceContainer> pTunerSpaceContainer;
    hr = CoCreateInstance(CLSID_SystemTuningSpaces,
        NULL,
        CLSCTX_INPROC_SERVER,
        IID_ITuningSpaceContainer,
        reinterpret_cast<void**>(&pTunerSpaceContainer));
    if (FAILED(hr) || !pTunerSpaceContainer)
    {
        // ErrorMessageBox(TEXT("BDASample: Failed to create tuning space container"));
        return hr;
    }
    // get the number of tuning spaces that have been created
    LONG lCount;
    hr = pTunerSpaceContainer->get_Count(&lCount);
    if (FAILED(hr))
    {
        //ErrorMessageBox(TEXT("BDASample: get_Count failed"));
        return hr;
    }
    // add the tuning spacing container values to the registry
    CComVariant varIndex(lCount+1);
    hr = pTunerSpaceContainer->Add(pIDVBTuningSpace, &varIndex);
    if (FAILED(hr))
    {
        //ErrorMessageBox(TEXT("BDASample: Failed to add new tuning space to registry"));
        return hr;
    }
    // create a copy of this tuning space for the
    // class member variable.
    hr = pIDVBTuningSpace->Clone(&m_pITuningSpace);
    if (FAILED(hr))
    {
        //ErrorMessageBox(TEXT("BDASample: Clone failed"));
        m_pITuningSpace = NULL;
        return hr;
    }
    pIDVBTuningSpace     = NULL;
    pIDVBTLocator        = NULL;
    pTunerSpaceContainer = NULL;
    return hr;
}
HRESULT  LoadTuningSpace(CComBSTR pNetworkType)
{
    HRESULT hr;
    ITuningSpace* pTuningSpace           = NULL;
    IEnumTuningSpaces* pEnumTuningSpaces = NULL;
    ITuningSpace** pTuningSpaceArray     = NULL;
    long lCount                          = 0;
    ULONG ulNumFetched = 0, i = 0;
    CComBSTR bstrTemp;
    OutputDebugString(TEXT("BDASample: CBDAFilterGraph:oadTuningSpace\n"));
    // Get the tuning space collection
    hr = CoCreateInstance(CLSID_SystemTuningSpaces, NULL,
        CLSCTX_INPROC_SERVER, IID_ITuningSpaceContainer,
        reinterpret_cast<void**>(&m_pTuningSpaceContainer));
    if (FAILED(hr))
    {
        //ErrorMessageBox(TEXT("Failed to create system tuning space."));
        return hr;
    }
    // Find the tuning space in the collection
    hr = m_pTuningSpaceContainer->get_EnumTuningSpaces(&pEnumTuningSpaces);
    if (FAILED(hr))
    {
        //ErrorMessageBox(TEXT("Failed to get tuning space enumerator."));
        return hr;
    }
    hr = m_pTuningSpaceContainer->get_Count(&lCount);
    if (FAILED(hr))
    {
        //ErrorMessageBox(TEXT("Failed to enumerate tuning spaces."));
        return hr;
    }
    // Read tuning space info into allocated array
    pTuningSpaceArray = new ITuningSpace*[lCount];
    hr = pEnumTuningSpaces->Next(lCount, pTuningSpaceArray, &ulNumFetched);
    if (FAILED(hr))
    {
        //ErrorMessageBox(TEXT("Failed to read tuning spaces."));
        return hr;
    }
    pEnumTuningSpaces = NULL;
    // Find the tuning space
    for (i = 0; i < ulNumFetched; i++)
    {
        hr = pTuningSpaceArray->get_UniqueName(&bstrTemp);
        if (FAILED(hr))
        {
            return hr;
        }
        // Is this the correct tuning space?
        if (bstrTemp == pNetworkType)
        {
            hr = pTuningSpaceArray->Clone(&pTuningSpace);
            break;
        }
    }
    pTuningSpaceArray = NULL;
    if (pTuningSpace == NULL)
    {
        return E_FAIL;
    }
    // QI for IDVBTuningSpace
    hr = pTuningSpace->QueryInterface(IID_IDVBTuningSpace, reinterpret_cast<void**>(&m_pITuningSpace));
    if (FAILED(hr))
    {
        return hr;
    }
    pTuningSpace = NULL;
    delete pTuningSpaceArray;
    return hr;
}


//判断是否有信号的函数

BOOL 　GetDemodLocked(BOOL* pDemodLocked)
{
    if ( !m_KsDemodPropSet )
    {
        return FALSE;
    }
    HRESULT hr;
    ULONG   ulBytesReturned;
    BOOL    bDemodLocked;
    DWORD   type_support = 0;
    // See if a demod. property set is supported
    hr = m_KsDemodPropSet->QuerySupported(KSPROPSETID_BdaSignalStats,
        KSPROPERTY_BDA_SIGNAL_LOCKED,
        &type_support);
    if (FAILED(hr))
    {
        return FALSE;
    }
    if (type_support & KSPROPERTY_SUPPORT_GET)
    {
        KSPROPERTY instance_data;
        instance_data.Id = KSPROPERTY_BDA_SIGNAL_LOCKED;
        // make call into driver
        hr = m_KsDemodPropSet->Get(KSPROPSETID_BdaSignalStats,
            KSPROPERTY_BDA_SIGNAL_LOCKED,
            &instance_data, sizeof(instance_data),
            &bDemodLocked, sizeof(bDemodLocked),
            &ulBytesReturned);
        if (FAILED(hr))
        {
            return FALSE;
        }
    }
    else
    {
        return FALSE;
    }
    *pDemodLocked = bDemodLocked;
    return TRUE;
}

这是比较完整的代码，构建Filter　Graph成功，Run也成功，就是接收不到频道信息以及节目数据？？？？？？？

alan1012

可否將你的完整 source code 寄給我看一下, 我的 mail address yushih_yang@yahoo.com.tw