Mobile上 Directshow開發Camera問題,该怎么解决

Mobile上 Directshow開發Camera問題
我們利用DirectShow開發Camera

平常都能正常開啟關閉

但連續開啟關閉數十次後，Camera會開始出現全黑畫面，

發現問題在於Transform filter 跟Render filter連接時失敗

ConnectFilters( pGraphBuilder, m_pTransformFilter, m_pRender );

C/C++ code

HRESULT ConnectFilters(IGraphBuilder *pGraph,IBaseFilter *pSrc,IBaseFilter *pDest)
{
    if(( !pGraph ) || ( !pSrc ) || ( !pDest )) return E_POINTER; 

    // Find an output pin on the first filter.
    HRESULT hr = E_FAIL; 
    CComPtr<IPin> pOut = NULL; 
    CHK( GetUnconnectedPin( pSrc, PINDIR_OUTPUT, &pOut )); 
    CHK( ConnectFilters( pGraph, pOut, pDest )); 

Cleanup:
    if( FAILED( hr ))
        RETAILMSG( 1, ( L"CAMERA >>> Connect Filters Failed...\r\n" )); 

    if( pOut )
        pOut.Release(); 

    return hr;
}

//=============================================================================
HRESULT ConnectFilters(IGraphBuilder *pGraph, IPin *pOut, IBaseFilter *pDest)
{
    if( (!pGraph) || (!pOut) || (!pDest) ) return E_POINTER; 

    // Find an input pin on the downstream filter.
    HRESULT hr = E_FAIL; 
    CComPtr<IPin> pIn = NULL; 
    CHK( GetUnconnectedPin( pDest, PINDIR_INPUT, &pIn )); 

    PIN_INFO pinInfo_OUT, pinInfo_IN; 
    memset( &pinInfo_OUT, 0, sizeof( PIN_INFO )); 
    memset( &pinInfo_IN, 0, sizeof( PIN_INFO )); 

    hr = pOut->QueryPinInfo( &pinInfo_OUT ); 
    hr = pIn->QueryPinInfo( &pinInfo_IN ); 

    // Try to connect them.
    CHK( pGraph->Connect( pOut, pIn )); 

Cleanup:
    if( FAILED( hr ))
        RETAILMSG( 1, ( L"CAMERA >>> Connect Pins Failed...\r\n" )); 

    if( pIn )
        pIn.Release(); 

    return hr;
}

//=============================================================================
HRESULT GetUnconnectedPin(IBaseFilter *pFilter,PIN_DIRECTION PinDir,IPin **ppPin)
{
    HRESULT hr = E_FAIL; 
    *ppPin = 0;
    CComPtr<IEnumPins> pEnum = NULL; 
    IPin *pPin = 0; 
    
    CHK( pFilter->EnumPins( &pEnum )); 

    while( pEnum->Next(1, &pPin, NULL) == S_OK )
    {
        PIN_DIRECTION ThisPinDir; 
        hr = pPin->QueryDirection( &ThisPinDir ); 
        if( ThisPinDir == PinDir )
        {
            CComPtr<IPin> pTmp = NULL; 
            hr = pPin->ConnectedTo(&pTmp); 
            if( SUCCEEDED( hr ))  // Already connected, not the pin we want.
            {
                pTmp.Release(); 
            }
            else  // Unconnected, this is the pin we want.
            {
                *ppPin = pPin; 
                hr = S_OK; 
                break; 
            }
        }
        pPin->Release(); 
    }

Cleanup:
    if( FAILED( hr ))
        RETAILMSG( 1, ( L"CAMERA >>> Get Unconnected Pin Failed...\r\n" )); 

    if( pEnum )
        pEnum.Release(); 

    return hr; 
}

檢驗此function後，發現有正確找出Transform filter的output pin及Render filter的Input pin

卻在連接兩個Pin時失敗，

hr = pOut->QueryPinInfo( &pinInfo_OUT ); <====S_Ok
hr = pIn->QueryPinInfo( &pinInfo_IN ); <====S_Ok

// Try to connect them.
hr = pGraph->Connect( pOut, pIn ); <====出現Error code為0x80040217

請問有可能是什麼原因照成這樣的情況發生呢??

------解决方案--------------------
0x80040217
VFW_E_CANNOT_CONNECT
No combination of intermediate filters could be found to make the connection.

应该是上游Filter能接受的媒体类型发生改变造成的，查查Video Capture Filter？

Mobile上 Directshow開發Camera問題,该怎么解决

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