直接上代码吧：
代码是参考网上大神分享的，在原基础上做了些修改(只检测视频设备)：
int DeviceIsBusy(char *videoName)
{
//输入设备的音视频名称
HRESULT hr;
HRESULT hhr;
int ret = ;
int videoBusy = ;
int audioBusy = ; CoInitialize(NULL); ICreateDevEnum* pSysDevEnum = NULL; hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER, IID_ICreateDevEnum, (void**)&pSysDevEnum); IEnumMoniker* pEnumCat; hr = pSysDevEnum->CreateClassEnumerator(CLSID_VideoInputDeviceCategory, &pEnumCat, ); if (hr == S_OK)
{
IMoniker* pMoniker = NULL;
IMoniker* pm1 = NULL;
ULONG cFetched; while (pEnumCat->Next(, &pMoniker, &cFetched) == S_OK)
{
IPropertyBag* pPropBag;
hr = pMoniker->BindToStorage(, , IID_IPropertyBag, (void**)&pPropBag); if (SUCCEEDED(hr))
{ VARIANT varName;
varName.vt = VT_BSTR; VariantInit(&varName); hr = pPropBag->Read(L"FriendlyName", &varName, ); USES_CONVERSION;
LPTSTR lpstrMsg = W2T(varName.bstrVal); std::wstring cs = (LPCTSTR)lpstrMsg;
std::string name_;
StringConverter::WStringToString(cs, name_); if (SUCCEEDED(hr))
{
if (!strcmp(videoName, name_.c_str()))//存在设备
{
LPBC *pbc = NULL;
IBaseFilter *P_VCamTrans = NULL;
IBaseFilter *pCap = NULL; CreateBindCtx(, pbc); hr = pMoniker->BindToObject((IBindCtx *)pbc, , IID_IBaseFilter, (void **)&pCap); ICaptureGraphBuilder2 *m_pCapGB;
IGraphBuilder *m_pGB;
IMediaControl *m_pMC;
IVideoWindow *m_pVW; hr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC, IID_IGraphBuilder, (void **)&m_pGB); if (FAILED(hr)) return hr; m_pGB->AddFilter(pCap, NULL); hr = CoCreateInstance(CLSID_CaptureGraphBuilder2, NULL, CLSCTX_INPROC_SERVER, IID_ICaptureGraphBuilder2, (void **)&m_pCapGB); if (FAILED(hr)) return hr; m_pCapGB->SetFiltergraph(m_pGB); IAMCrossbar *pXBar1 = NULL; hr = m_pCapGB->FindInterface(&LOOK_UPSTREAM_ONLY, NULL, pCap, IID_IAMCrossbar, (void **)&pXBar1); if (SUCCEEDED(hr))
{
long OutputPinCount;
long InputPinCount;
long PinIndexRelated;
long PhysicalType;
long inPort = ;
long outPort = ; pXBar1->get_PinCounts(&OutputPinCount, &InputPinCount); //对于存在输入输出引脚的摄像头。此处采用轮询所有的引脚
for (int i = ; i < InputPinCount; i++)
{
pXBar1->get_CrossbarPinInfo(TRUE, i, &PinIndexRelated, &PhysicalType); if (PhysConn_Video_Composite == PhysicalType)
{
inPort = i;
break;
} } for (int i = ; i < OutputPinCount; i++)
{
pXBar1->get_CrossbarPinInfo(FALSE, i, &PinIndexRelated, &PhysicalType); if (PhysConn_Video_VideoDecoder == PhysicalType)
{
outPort = i;
break;
}
} for (int i = ; i < InputPinCount; i++)
{
for (int j = ; j < OutputPinCount; j++)
{
if (S_OK == pXBar1->CanRoute(j, i))
{
pXBar1->Route(j, i); m_pGB->AddFilter(pCap, L"Capture Filter");
m_pGB->QueryInterface(IID_IMediaControl, (void **)&m_pMC);
hr = m_pGB->QueryInterface(IID_IVideoWindow, (LPVOID*)&m_pVW);
hr = m_pCapGB->RenderStream(NULL, NULL, pCap, NULL, P_VCamTrans); hr = m_pVW->put_Owner((OAHWND)NULL);
hr = m_pVW->put_WindowStyle(WS_CHILD | WS_CLIPCHILDREN);
hr = m_pVW->put_Visible(OAFALSE);
hr = m_pVW->put_AutoShow(OAFALSE); hhr = m_pMC->StopWhenReady(); if (SUCCEEDED(hhr))
{
videoBusy = ;
} }
}
} if (videoBusy == )
{
ret = -; //视频设备占用
}
}
else
{
m_pGB->AddFilter(pCap, L"Capture Filter");
m_pGB->QueryInterface(IID_IMediaControl, (void **)&m_pMC);
hr = m_pGB->QueryInterface(IID_IVideoWindow, (LPVOID*)&m_pVW);
hr = m_pCapGB->RenderStream(NULL, NULL, pCap, NULL, P_VCamTrans); hr = m_pVW->put_Owner((OAHWND)NULL);
hr = m_pVW->put_WindowStyle(WS_CHILD | WS_CLIPCHILDREN);
hr = m_pVW->put_Visible(OAFALSE);
hr = m_pVW->put_AutoShow(OAFALSE); hhr = m_pMC->StopWhenReady(); if (FAILED(hhr))
{
ret = -; //视频设备占用
} }
//如果找到设备匹配的就直接跳出循环
break;
} } pPropBag->Release(); }
pMoniker->Release();
} }
pSysDevEnum->Release(); CoUninitialize(); return ret;
}
上面代码是只检测视频设备，然后稍微改了一点逻辑。
下面是原始代码仅供参考：
int DeviceIsBusy(char *videoName,char *audioName)
{
//输入设备的音视频名称
HRESULT hr;
HRESULT hhr;
int ret=;
int videoBusy=;
int audioBusy=; CoInitialize(NULL); ICreateDevEnum* pSysDevEnum = NULL; hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER, IID_ICreateDevEnum, (void**)&pSysDevEnum); IEnumMoniker* pEnumCat ; hr = pSysDevEnum->CreateClassEnumerator(CLSID_VideoInputDeviceCategory, &pEnumCat, ); if(hr == S_OK)
{
IMoniker* pMoniker = NULL;
IMoniker* pm1=NULL;
ULONG cFetched; while(pEnumCat->Next(, &pMoniker, &cFetched) == S_OK)
{
IPropertyBag* pPropBag;
hr = pMoniker->BindToStorage(, , IID_IPropertyBag, (void**)&pPropBag); if(SUCCEEDED(hr))
{ VARIANT varName;
varName.vt=VT_BSTR; VariantInit(&varName); hr = pPropBag->Read(L"FriendlyName", &varName, ); USES_CONVERSION;
LPTSTR lpstrMsg = W2T(varName.bstrVal); if(SUCCEEDED(hr))
{
if (!strcmp(videoName,lpstrMsg))//存在设备
{
LPBC *pbc=NULL;
IBaseFilter *P_VCamTrans=NULL;
IBaseFilter *pCap=NULL; CreateBindCtx(,pbc); hr=pMoniker->BindToObject((IBindCtx *)pbc,,IID_IBaseFilter,(void **)&pCap); ICaptureGraphBuilder2 *m_pCapGB;
IGraphBuilder *m_pGB;
IMediaControl *m_pMC;
IVideoWindow *m_pVW; hr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC, IID_IGraphBuilder, (void **)&m_pGB); if (FAILED(hr)) return hr; m_pGB->AddFilter(pCap,NULL); hr = CoCreateInstance(CLSID_CaptureGraphBuilder2, NULL,CLSCTX_INPROC_SERVER, IID_ICaptureGraphBuilder2, (void **)&m_pCapGB); if (FAILED(hr)) return hr; m_pCapGB->SetFiltergraph(m_pGB); IAMCrossbar *pXBar1 = NULL; hr=m_pCapGB->FindInterface(&LOOK_UPSTREAM_ONLY,NULL,pCap,IID_IAMCrossbar,(void **)&pXBar1); if (SUCCEEDED(hr))
{
long OutputPinCount;
long InputPinCount;
long PinIndexRelated;
long PhysicalType;
long inPort = ;
long outPort = ; pXBar1->get_PinCounts(&OutputPinCount,&InputPinCount); //对于存在输入输出引脚的摄像头。此处采用轮询所有的引脚
for(int i =;i<InputPinCount;i++)
{
pXBar1->get_CrossbarPinInfo(TRUE,i,&PinIndexRelated,&PhysicalType); if(PhysConn_Video_Composite==PhysicalType)
{
inPort = i;
break;
} } for(int i =;i<OutputPinCount;i++)
{
pXBar1->get_CrossbarPinInfo(FALSE,i,&PinIndexRelated,&PhysicalType); if(PhysConn_Video_VideoDecoder==PhysicalType)
{
outPort = i;
break;
}
} for (int i=;i<InputPinCount;i++)
{
for (int j=;j<OutputPinCount;j++)
{
if(S_OK==pXBar1->CanRoute(j,i))
{
pXBar1->Route(j,i); m_pGB->AddFilter(pCap, L"Capture Filter");
m_pGB->QueryInterface(IID_IMediaControl, (void **)&m_pMC);
hr = m_pGB->QueryInterface(IID_IVideoWindow,(LPVOID*)&m_pVW);
hr = m_pCapGB->RenderStream(NULL, NULL, pCap, NULL, P_VCamTrans); hr = m_pVW->put_Owner((OAHWND)NULL);
hr = m_pVW->put_WindowStyle( WS_CHILD | WS_CLIPCHILDREN);
hr = m_pVW->put_Visible(OAFALSE);
hr=m_pVW->put_AutoShow(OAFALSE); hhr=m_pMC->StopWhenReady(); if (SUCCEEDED(hhr))
{
videoBusy=;
} }
}
} if (videoBusy == )
{
ret=-; //视频设备占用
}
}
else
{
m_pGB->AddFilter(pCap, L"Capture Filter");
m_pGB->QueryInterface(IID_IMediaControl, (void **)&m_pMC);
hr = m_pGB->QueryInterface(IID_IVideoWindow,(LPVOID*)&m_pVW);
hr = m_pCapGB->RenderStream(NULL, NULL, pCap, NULL, P_VCamTrans); hr = m_pVW->put_Owner((OAHWND)NULL);
hr = m_pVW->put_WindowStyle( WS_CHILD | WS_CLIPCHILDREN);
hr = m_pVW->put_Visible(OAFALSE);
hr=m_pVW->put_AutoShow(OAFALSE); hhr=m_pMC->StopWhenReady(); if (FAILED(hhr))
{
ret=-; //视频设备占用
} } } } pPropBag->Release(); }
pMoniker->Release();
} } //判断音频的方法和上面的一样 重复。
hr = pSysDevEnum->CreateClassEnumerator(CLSID_AudioInputDeviceCategory, &pEnumCat, ); if(hr == S_OK)
{
IMoniker* pMoniker = NULL;
IMoniker* pm1=NULL;
ULONG cFetched; while(pEnumCat->Next(, &pMoniker, &cFetched) == S_OK)
{
IPropertyBag* pPropBag;
hr = pMoniker->BindToStorage(, , IID_IPropertyBag, (void**)&pPropBag); if(SUCCEEDED(hr))
{ VARIANT varName;
varName.vt=VT_BSTR; VariantInit(&varName); hr = pPropBag->Read(L"FriendlyName", &varName, ); USES_CONVERSION;
LPTSTR lpstrMsg = W2T(varName.bstrVal); if(SUCCEEDED(hr))
{
if (!strcmp(videoName,lpstrMsg))//存在设备
{
LPBC *pbc=NULL;
IBaseFilter *P_VCamTrans=NULL;
IBaseFilter *pCap=NULL; CreateBindCtx(,pbc); hr=pMoniker->BindToObject((IBindCtx *)pbc,,IID_IBaseFilter,(void **)&pCap); ICaptureGraphBuilder2 *m_pCapGB;
IGraphBuilder *m_pGB;
IMediaControl *m_pMC;
IVideoWindow *m_pVW; hr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC, IID_IGraphBuilder, (void **)&m_pGB); if (FAILED(hr)) return hr; m_pGB->AddFilter(pCap,NULL); hr = CoCreateInstance(CLSID_CaptureGraphBuilder2, NULL,CLSCTX_INPROC_SERVER, IID_ICaptureGraphBuilder2, (void **)&m_pCapGB); if (FAILED(hr)) return hr; m_pCapGB->SetFiltergraph(m_pGB); IAMCrossbar *pXBar1 = NULL; hr=m_pCapGB->FindInterface(&LOOK_UPSTREAM_ONLY,NULL,pCap,IID_IAMCrossbar,(void **)&pXBar1); if (SUCCEEDED(hr))
{
long OutputPinCount;
long InputPinCount;
long PinIndexRelated;
long PhysicalType;
long inPort = ;
long outPort = ; pXBar1->get_PinCounts(&OutputPinCount,&InputPinCount); for(int i =;i<InputPinCount;i++)
{
pXBar1->get_CrossbarPinInfo(TRUE,i,&PinIndexRelated,&PhysicalType); if(PhysConn_Video_Composite==PhysicalType)
{
inPort = i;
break;
} } for(int i =;i<OutputPinCount;i++)
{
pXBar1->get_CrossbarPinInfo(FALSE,i,&PinIndexRelated,&PhysicalType); if(PhysConn_Video_VideoDecoder==PhysicalType)
{
outPort = i;
break;
}
} for (int i=;i<InputPinCount;i++)
{
for (int j=;j<OutputPinCount;j++)
{
if(S_OK==pXBar1->CanRoute(j,i))
{
pXBar1->Route(j,i); m_pGB->AddFilter(pCap, L"Capture Filter");
m_pGB->QueryInterface(IID_IMediaControl, (void **)&m_pMC);
hr = m_pGB->QueryInterface(IID_IVideoWindow,(LPVOID*)&m_pVW);
hr = m_pCapGB->RenderStream(NULL, NULL, pCap, NULL, P_VCamTrans); hr = m_pVW->put_Owner((OAHWND)NULL);
hr = m_pVW->put_WindowStyle( WS_CHILD | WS_CLIPCHILDREN);
hr = m_pVW->put_Visible(OAFALSE);
hr=m_pVW->put_AutoShow(OAFALSE); hhr=m_pMC->StopWhenReady(); if (SUCCEEDED(hhr))
{
audioBusy=;
} }
}
} if (audioBusy == )
{
ret=-; //音频设备占用
}
}
else
{
m_pGB->AddFilter(pCap, L"Capture Filter");
m_pGB->QueryInterface(IID_IMediaControl, (void **)&m_pMC);
hr = m_pGB->QueryInterface(IID_IVideoWindow,(LPVOID*)&m_pVW);
hr = m_pCapGB->RenderStream(NULL, NULL, pCap, NULL, P_VCamTrans); hr = m_pVW->put_Owner((OAHWND)NULL);
hr = m_pVW->put_WindowStyle( WS_CHILD | WS_CLIPCHILDREN);
hr = m_pVW->put_Visible(OAFALSE);
hr=m_pVW->put_AutoShow(OAFALSE); hhr=m_pMC->StopWhenReady(); if (FAILED(hhr))
{
ret=-; //音频设备占用
} } } } pPropBag->Release(); }
pMoniker->Release();
} } pSysDevEnum->Release(); CoUninitialize(); return ret;
}
转载地址：http://blog.csdn.net/ren65432/article/details/43086975