【发布时间】：2014-02-28 16:05:56
【问题描述】：
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);
}
另外请注意，我可以在 graphedit 中导入我的过滤器
【问题讨论】：
-
你试过用 COINIT_APARTMENTTHREADED 而不是 CoInitialize(NULL) 调用 CoInitializeEx 吗？
-
未发布相关代码。
MyFilter::NonDelegatingQueryInterface是你应该看的地方。
标签： c++ com directshow