dshow枚举设备,声音回放...

 

HRESULT EnumerateAudioOutputFilters(IBaseFilter  ** pFilter)
... {
    HRESULT hr;
    ULONG cFetched;
    ICreateDevEnum *pSysDevEnum = NULL;
    IEnumMoniker *pEnumCat = NULL;
    IMoniker *pMoniker = NULL;
    char szDevName[MAX_PATH] = ...{0};

    // 创建系统设备枚举COM对象.
    if (FAILED(hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC, 
                                                IID_ICreateDevEnum, (void **)&pSysDevEnum)))
    ...{
        return hr;
    }
    
    // 创建音频输出设备枚举COM对象.
    if (FAILED(hr = pSysDevEnum->CreateClassEnumerator(CLSID_AudioRendererCategory, &pEnumCat, 0)))
    ...{
        pSysDevEnum->Release();
        return hr;
    }
    
    // 系统循环枚举音频输出设备表.
    while(pEnumCat->Next(1, &pMoniker, &cFetched) == S_OK)
    ...{
        IPropertyBag *pPropBag;
        VARIANT varName;

        varName.vt = VT_BSTR;

        // 绑定设备属性到一个COM对象.
        if (FAILED(pMoniker->BindToStorage(0, 0, IID_IPropertyBag, (void **)&pPropBag)))
        ...{
            goto FAILED_RET;
        }            
        
        // 读取属性中的设备名称项.
        if (FAILED(hr = pPropBag->Read(L"FriendlyName", &varName, 0)))
        ...{
            pPropBag->Release();
            goto FAILED_RET;
        }    
        
        WideCharToMultiByte(CP_ACP, 0, varName.bstrVal, wcslen(varName.bstrVal), szDevName, MAX_PATH, NULL, NULL); 
        TRACE1("Audio Output Device: %s ", szDevName);

        // 设置条件,绑定到过滤器.
        if (FAILED(hr = pMoniker->BindToObject(NULL, NULL, IID_IBaseFilter, (void**)pFilter)))
        ...{            
            pPropBag->Release();
            pMoniker->Release();
            goto FAILED_RET;
        }        
        
        SysFreeString(varName.bstrVal);
        pPropBag->Release();
        pMoniker->Release();
    }

FAILED_RET:
    pEnumCat->Release();
    pSysDevEnum->Release();

    return hr;
}

HRESULT EnumerateAudioInputFilters(IBaseFilter  ** pFilter)
... {
    HRESULT hr;
    ULONG cFetched;
    ICreateDevEnum *pSysDevEnum = NULL;
    IEnumMoniker *pEnumCat = NULL;
    IMoniker *pMoniker = NULL;
    char szDevName[MAX_PATH] = ...{0};
        
    // 创建系统设备枚举COM对象.
    if (FAILED(hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC, 
                                                IID_ICreateDevEnum, (void **)&pSysDevEnum)))
    ...{
        return hr;
    }
    
    // 创建音频输出设备枚举COM对象.
    if (FAILED(hr = pSysDevEnum->CreateClassEnumerator(CLSID_AudioInputDeviceCategory, &pEnumCat, 0)))
    ...{
        pSysDevEnum->Release();
        return hr;
    }
    
    // 系统循环枚举音频输出设备表.
    while(pEnumCat->Next(1, &pMoniker, &cFetched) == S_OK)
    ...{
        IPropertyBag *pPropBag;
        VARIANT varName;
        
        varName.vt = VT_BSTR;
        
        // 绑定设备属性到一个COM对象.
        if (FAILED(pMoniker->BindToStorage(0, 0, IID_IPropertyBag, (void **)&pPropBag)))
        ...{
            goto FAILED_RET;
        }
        
        // 读取属性中的设备名称项.
        if (FAILED(hr = pPropBag->Read(L"FriendlyName", &varName, 0)))
        ...{
            pPropBag->Release();
            goto FAILED_RET;
        }
        
        WideCharToMultiByte(CP_ACP, 0, varName.bstrVal, wcslen(varName.bstrVal), szDevName, MAX_PATH, NULL, NULL); 
        TRACE1("Audio Input Device: %s ", szDevName);
        
        // 设置条件,绑定到过滤器.
        if (FAILED(hr = pMoniker->BindToObject(NULL, NULL, IID_IBaseFilter, (void**)pFilter)))
        ...{            
            pPropBag->Release();
            pMoniker->Release();
            goto FAILED_RET;
        }        
        
        SysFreeString(varName.bstrVal);
        pPropBag->Release();
        pMoniker->Release();
    }
    
FAILED_RET:
    pEnumCat->Release();
    pSysDevEnum->Release();
    
    return hr;
}

int  main( int  argc,  char *  argv[])
... {
    IGraphBuilder            *pGraph;
    ICaptureGraphBuilder2    *pBuilder;
    IMediaControl            *pMediaControl;
    IMediaEvent                *pEvent;
    IBaseFilter                *pSrc;
    IBaseFilter                *pDst;
    HRESULT                    hr;

    CoInitialize(NULL);

    // 设置各接口.
    EnumerateAudioInputFilters(&pSrc);
    EnumerateAudioOutputFilters(&pDst);
  
    if (FAILED(hr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC_SERVER, IID_IGraphBuilder, (void **)&pGraph)))
    ...{
        return 1;
    }

    if (FAILED(hr = CoCreateInstance(CLSID_CaptureGraphBuilder2, NULL, CLSCTX_INPROC, IID_ICaptureGraphBuilder2, (void **)&pBuilder)))
    ...{
        return 2;
    }

    if (FAILED(hr = pBuilder->SetFiltergraph(pGraph)))
    ...{
        return 3;
    }

    if (FAILED(pGraph->AddFilter(pDst, L"Audio Renderers")))
    ...{
        return 4;
    }

    if (FAILED(pGraph->AddFilter(pSrc, L"Audio Capture")))
    ...{
        return 5;
    }

    if (FAILED(hr = pBuilder->RenderStream(
        &PIN_CATEGORY_CAPTURE,  // Pin category
        &MEDIATYPE_Audio,       // Media type
        pSrc,                   // Capture filter
        NULL,                   // Compression filter (optional)
        NULL                    // Multiplexer or renderer filter
        )))
    ...{
        return 6;
    }

    pDst->Release();
    pSrc->Release();

    // 查询接口.
    if (FAILED(hr = pGraph->QueryInterface(IID_IMediaControl, (void **)&pMediaControl)))
    ...{
        return 7;
    }

    if (FAILED(hr = pGraph->QueryInterface(IID_IMediaEvent, (void **)&pEvent)))
    ...{
        return 8;
    }

    // 开始运行.
    if (FAILED(hr = pMediaControl->Run()))
    ...{
        return 9;
    }
    
    // 等待完成. 
    long evCode;
    if (FAILED(hr = pEvent->WaitForCompletion(INFINITE, &evCode)))
    ...{
        return 10;
    }
    
    // 撤消.
    pMediaControl->Release();
    pEvent->Release();
    pBuilder->Release();
    pGraph->Release();

    CoUninitialize();

    return 0;
}