用于直接显示筛选器的 CoCreateInstance 返回E_NOINTERFACE

我已经成功编译并注册了一个直接显示过滤器。现在我想在我的代码中使用它。但是对 COCreateInstance 的调用会返回错误代码E_NOINTERFACE。

这是我的过滤器的注册码

 #include "MyFilter.h"
#include <aviriff.h>
static WCHAR g_wszName[] = L"MyFilter";
CFactoryTemplate g_Templates[] = 
{
  { 
    g_wszName,
        &CLSID_MyFilter,
        MyFilter::CreateInstance,
    NULL,
    NULL
  }
};
int g_cTemplates = sizeof(g_Templates) / sizeof(g_Templates[0]); 

// Declare media type information.
FOURCCMap fccMap = FCC('MRLE'); 
REGPINTYPES sudInputTypes = { &MEDIATYPE_Video, &GUID_NULL };
REGPINTYPES sudOutputTypes = { &MEDIATYPE_Video, (GUID*)&fccMap };
// Declare pin information.
REGFILTERPINS sudPinReg[] = {
    // Input pin.
    { TEXT("PinInput0"), FALSE, // Rendered?
         FALSE, // Output?
         FALSE, // Zero?
         FALSE, // Many?
         0, 0, 
         1, &sudInputTypes  // Media types.
    },
    { TEXT("PinInput1"), FALSE,
        FALSE,
        FALSE,
        FALSE,
        0, 0, 1, &sudInputTypes
    },
    {
        TEXT("PinInput2"), FALSE,
            FALSE,
            FALSE,
            FALSE,
            0, 0, 1, &sudInputTypes
    },
    // Output pin.
    { 0, FALSE, // Rendered?
         TRUE, // Output?
         FALSE, // Zero?
         FALSE, // Many?
         0, 0, 
         1, &sudOutputTypes      // Media types.
    }
};
// Declare filter information.
REGFILTER2 rf2FilterReg = {
    1,                // Version number.
    MERIT_DO_NOT_USE, // Merit.
    4,                // Number of pins.
    sudPinReg         // Pointer to pin information.
};
STDAPI DllRegisterServer(void)
{
    HRESULT hr = AMovieDllRegisterServer2(TRUE);
    if (FAILED(hr))
    {
        return hr;
    }
    IFilterMapper2 *pFM2 = NULL;
    hr = CoCreateInstance(CLSID_FilterMapper2, NULL, CLSCTX_INPROC_SERVER,
            IID_IFilterMapper2, (void **)&pFM2);
    if (SUCCEEDED(hr))
    {
        hr = pFM2->RegisterFilter(
            CLSID_MyFilter,                // Filter CLSID. 
            g_wszName,                       // Filter name.
            NULL,                            // Device moniker. 
            &CLSID_VideoCompressorCategory,  // Video compressor category.
            g_wszName,                       // Instance data.
            &rf2FilterReg                    // Filter information.
            );
        pFM2->Release();
    }
    return hr;
}
STDAPI DllUnregisterServer()
{
    HRESULT hr = AMovieDllRegisterServer2(FALSE);
    if (FAILED(hr))
    {
        return hr;
    }
    IFilterMapper2 *pFM2 = NULL;
    hr = CoCreateInstance(CLSID_FilterMapper2, NULL, CLSCTX_INPROC_SERVER,
            IID_IFilterMapper2, (void **)&pFM2);
    if (SUCCEEDED(hr))
    {
        hr = pFM2->UnregisterFilter(&CLSID_VideoCompressorCategory, 
            g_wszName, CLSID_MyFilter);
        pFM2->Release();
    }
    return hr;
}

extern "C" BOOL WINAPI DllEntryPoint(HINSTANCE, ULONG, LPVOID);
BOOL APIENTRY DllMain(HANDLE hModule, DWORD dwReason, LPVOID lpReserved)
{
    return DllEntryPoint((HINSTANCE)(hModule), dwReason, lpReserved);
}

这里是使用过滤器的代码

#include <DShow.h>
#include "MyFilter.h"
#include <streams.h>

IPin *GetPin(IBaseFilter *pFilter, PIN_DIRECTION PinDir)
{
    BOOL       bFound = FALSE;
    IEnumPins  *pEnum;
    IPin       *pPin;
    pFilter->EnumPins(&pEnum);
    while(pEnum->Next(1, &pPin, 0) == S_OK)
    {
        PIN_DIRECTION PinDirThis;
        pPin->QueryDirection(&PinDirThis);
        if (bFound = (PinDir == PinDirThis))
            break;
        pPin->Release();
    }
    pEnum->Release();
    return (bFound ? pPin : 0);  
}

int CALLBACK WinMain(
  _In_  HINSTANCE hInstance,
  _In_  HINSTANCE hPrevInstance,
  _In_  LPSTR lpCmdLine,
  _In_  int nCmdShow
)
{
    CoInitialize(NULL);
    IGraphBuilder* pGraph = NULL;
    IMediaControl* pMediaControl = NULL;
    IMediaEvent* pMediaEvent = NULL;
    HRESULT hr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_ALL, IID_IFilterGraph, (void **) &pGraph);
    if(hr < 0)
    {
        return -1;
    }
    IBaseFilter* pSource = NULL;
    pGraph->QueryInterface(IID_IMediaControl, (void **) pMediaControl);
    pGraph->QueryInterface(IID_IMediaEvent, (void **) pMediaEvent);
    pGraph->AddSourceFilter(TEXT("C:\TEMP\video1.avi"), 0, &pSource);
    IPin* pSourceOut = GetPin(pSource, PINDIR_OUTPUT);
    IBaseFilter* pAVISplitter = NULL;
    CoCreateInstance(CLSID_AviSplitter, NULL,   
                             CLSCTX_INPROC_SERVER,
                             IID_IBaseFilter,
              (void**)&pAVISplitter);
    IPin* pAvIIn = GetPin(pAVISplitter, PINDIR_INPUT);
    pGraph->AddFilter(pAVISplitter, L"Splitter");
    pGraph->Connect(pSourceOut, pAvIIn);
    IPin* pAVIOut = GetPin(pAVISplitter, PINDIR_OUTPUT);

    MyFilter* myfilter;
    hr = CoCreateInstance(CLSID_MyFilter, NULL, CLSCTX_INPROC_SERVER, IID_MyFilter, (void **)& myfilter);
    if(hr < 0)
    {
        return -1;
    }
    IPin* myfilterIn = myfilter->GetPin(0);
    IPin* myFilterOut = myfilter->GetPin(3);
    pGraph->Connect(pAVIOut, myfilterIn);
    pGraph->Render(myFilterOut);
    CoUninitialize();

    return 0;
}

只需调用基类：

STDMETHODIMP MyFilter::NonDelegatingQueryInterface(REFIID riid, void **ppv)
{
    return CBaseFilter::NonDelegatingQueryInterface(riid, ppv);
}

另请注意，我可以在图形编辑器中导入我的过滤器