C++DirectShow检测音视频输入设备及其采集参数

[C++]DirectShow检测⾳视频输⼊设备及其采集参数创建CLR类库项⽬（CSharpDirectShow），编写托管的DirectShow类库，右键项⽬属性-->链接器-->输⼊-->附加依赖项；添加静态库⽂件Strmiids.lib和Quartz.lib；定义头⽂件CSharpDirectShow.h，包含头⽂件dshow.h，定义如下⽅法：#pragmaonce#include<dshow.h>usingnamespaceSystem;usingnamespaceSystem::Runtime::InteropServices;publicrefclassDirectShow{public:///<summary>///在当前线程上初始化COM库，并将并发模型标识为单线程单元（STA）///</summary>///<returns></returns>staticBooleanComInit();///<summary>///关闭当前线程上的COM库，卸载该线程加载的所有DLL，释放该线程维护的所有其他资源，并强制关闭该线程上的所有RPC连接///</summary>staticvoidComUinit();///<summary>///获取视频输⼊设备///</summary>///<paramname="devices"></param>///<returns></returns>staticInt32GetVideoInputDevices([Out]array<VideoInputDsDevice^>^%devices);///<summary>///获取⾳频输⼊设备///</summary>///<paramname="device"></param>///<returns></returns>staticInt32GetAudioInputDevices([Out]array<AudioInputDsDevice^>^%device);};其中，初始化COM库只能在STA线程调⽤，控制台程序直接调⽤会返回失败，在Winform和WPF等应⽤程序应该在第⼀次使⽤时初始化COM库；当前线程初始化COM库和关闭COM库：BooleanDirectShow::ComInit(){HRESULThr=CoInitialize(NULL);returnhr==S_OK||hr==S_FALSE;}voidDirectShow::ComUinit(){CoUninitialize();}1、创建视频输⼊设备的枚举器IEnumMonikerHRESULTDirectShow::EnumerateDevices(REFGUIDcategory,IEnumMoniker**ppEnum){//创建系统设备枚举器ICreateDevEnum*pDevEnum;HRESULThr=CoCreateInstance(CLSID_SystemDeviceEnum,NULL,CLSCTX_INPROC_SERVER,IID_PPV_ARGS(&pDevEnum));if(SUCCEEDED(hr)){//为类别创建枚举数.hr=pDevEnum->CreateClassEnumerator(category,ppEnum,0);if(hr==S_FALSE)hr=VFW_E_NOT_FOUND;//类别是空的，视为错误pDevEnum->Release();}returnhr;}Int32DirectShow::GetVideoInputDevices([Out]array<VideoInputDsDevice^>^%devices){devices=nullptr;IEnumMoniker*pEnum;HRESULThr=EnumerateDevices(CLSID_VideoInputDeviceCategory,&pEnum);//创建视频输⼊设备枚举器if(FAILED(hr))returnhr;hr=EnumerateVideoInputDevices(pEnum,devices);//枚举视频输⼊设备pEnum->Release();returnhr;}2、调⽤IEnumMoniker::Next()⽅法枚举设备，调⽤IPropertyBag::Read⽅法读取设备属性，以获取设备的友好名称和设备标识字符串：HRESULTDirectShow::EnumerateVideoInputDevices(IEnumMoniker*pEnum,[Out]array<VideoInputDsDevice^>^%devices){HRESULThr=S_FALSE;devices=nullptr;List<VideoInputDsDevice^>^list=gcnewList<VideoInputDsDevice^>();IMoniker*pMoniker;while(pEnum->Next(1,&pMoniker,NULL)==S_OK){IPropertyBag*pPropBag;hr=pMoniker->BindToStorage(0,0,IID_PPV_ARGS(&pPropBag));if(FAILED(hr)){pMoniker->Release();continue;}VideoInputDsDevice^device=gcnewVideoInputDsDevice();VARIANTvar;VariantInit(&var);//获取设备友好名hr=pPropBag->Read(L"FriendlyName",&var,0);if(FAILED(hr))hr=pPropBag->Read(L"Description",&var,0);if(SUCCEEDED(hr)){device->FriendlyName=System::String(var.bstrVal).ToString();VariantClear(&var);}//获取设备Moniker名LPOLESTRpOleDisplayName=reinterpret_cast<LPOLESTR>(CoTaskMemAlloc(MAX_MONIKER_NAME_LENGTH*2));hr=pMoniker->GetDisplayName(NULL,NULL,&pOleDisplayName);if(SUCCEEDED(hr)){device->MonikerName=System::String(pOleDisplayName).ToString();array<VideoParams^>^params;hr=EnumerateVideoParams(pMoniker,params);//枚举设备的采集参数if(SUCCEEDED(hr))device->Params=params;}CoTaskMemFree(pOleDisplayName);list->Add(device);pPropBag->Release();pMoniker->Release();}devices=list->ToArray();returnS_OK;}3、枚举视频输⼊设备的采集参数：HRESULTDirectShow::EnumerateVideoParams(IMoniker*pMoniker,[Out]array<VideoParams^>^%params){params=nullptr;IBaseFilter*pFilter;HRESULThr=pMoniker->BindToObject(NULL,NULL,IID_IBaseFilter,(void**)&pFilter);if(FAILED(hr))returnhr;IEnumPins*pinEnum;hr=pFilter->EnumPins(&pinEnum);if(FAILED(hr)){pFilter->Release();returnhr;}List<VideoParams^>^list=gcnewList<VideoParams^>();IPin*pPins;while(pinEnum->Next(1,&pPins,NULL)==S_OK){PIN_INFOpinInfo;hr=pPins->QueryPinInfo(&pinInfo);if(FAILED(hr)||pinInfo.dir!=PINDIR_OUTPUT){pPins->Release();continue;}IEnumMediaTypes*mtEnum;hr=pPins->EnumMediaTypes(&mtEnum);if(FAILED(hr)){pPins->Release();continue;}AM_MEDIA_TYPE*mt;while(mtEnum->Next(1,&mt,NULL)==S_OK){VideoParams^param=nullptr;if(mt->formattype==FORMAT_VideoInfo){VIDEOINFOHEADER*pVih=reinterpret_cast<VIDEOINFOHEADER*>(mt->pbFormat);param=gcnewVideoParams();param->FrameWidth=pVih->bmiHeader.biWidth;param->FrameHeight=pVih->bmiHeader.biHeight;param->AverageFrameRate=pVih->AvgTimePerFrame==0?0:10000000/pVih->AvgTimePerFrame;}elseif(mt->formattype==FORMAT_VideoInfo2){VIDEOINFOHEADER2*pVih=reinterpret_cast<VIDEOINFOHEADER2*>(mt->pbFormat);param=gcnewVideoParams();param->FrameWidth=pVih->bmiHeader.biWidth;param->FrameHeight=pVih->bmiHeader.biHeight;param->AverageFrameRate=pVih->AvgTimePerFrame==0?0:10000000/pVih->AvgTimePerFrame;}if(param&¶m->AverageFrameRate>1){BooleanisExit=false;foreach(VideoParams^iteminlist){if(item->FrameWidth==param->FrameWidth&&item->FrameHeight==param->FrameHeight&&item->AverageFrameRate==param->AverageFrameRate){isExit=true;break;}}if(!isExit)list->Add(param);}}pPins->Release();}pFilter->Release();params=list->ToArray();returnS_OK;}调⽤代码及结果：varret=DirectShow.GetVideoInputDevices(outVideoInputDsDevice[]videoInputDevices);if(ret==0){Console.WriteLine("视频输⼊设备：");foreach(varvideoInputDeviceinvideoInputDevices){Console.WriteLine($"{videoInputDevice.FriendlyName}\t{videoInputDevice.MonikerName}");if(videoInputDevice.Params.Length>0){Console.WriteLine("像素宽度\t像素⾼度\t1秒平均帧数");foreach(varparaminvideoInputDevice.Params){Console.WriteLine($"{param.FrameWidth}\t{param.FrameHeig