【发布时间】：2012-02-12 21:42:43
【问题描述】：
我正在尝试使用 C/C++ 应用程序中的 MIXER API 来控制 Windows 7 中的麦克风增强（电平/（取消）静音），但我没有获得相同的控件。可以使用 WASAPI 完成吗？有人可以建议任何其他 API 来控制 Windows 7 中的麦克风增强功能吗？
这是我目前为止写的……
const IID IID_IDeviceTopology = __uuidof(IDeviceTopology);
const IID IID_IPart = __uuidof(IPart);
const IID IID_IAudioAutoGainControl = __uuidof(IAudioAutoGainControl);
HRESULT hr = S_OK;
CoInitialize(NULL);
IMMDeviceEnumerator *deviceEnumerator = NULL;
hr = CoCreateInstance(__uuidof(MMDeviceEnumerator), NULL, CLSCTX_INPROC_SERVER, __uuidof(IMMDeviceEnumerator), (LPVOID *)&deviceEnumerator);
IMMDevice *pEndptDev = NULL;
hr = deviceEnumerator->GetDefaultAudioEndpoint(eCapture, eConsole, &pEndptDev);
deviceEnumerator->Release();
deviceEnumerator = NULL;
IDeviceTopology *pDevTopoEndpt = NULL;
IConnector *pConnEndpt = NULL;
IConnector *pConnHWDev = NULL;
IPart *pPartConn = NULL;
IAudioAutoGainControl *pAGC = NULL;
IControlInterface *pControl = NULL;
UINT pCount = 0;
LPCGUID pIID = ;
// Get the endpoint device's IDeviceTopology interface.
hr = pEndptDev->Activate(IID_IDeviceTopology, CLSCTX_ALL, NULL, (void**)&pDevTopoEndpt);
// The device topology for an endpoint device always
// contains just one connector (connector number 0).
hr = pDevTopoEndpt->GetConnector(0, &pConnEndpt);
// Use the connector in the endpoint device to get the
// connector in the adapter device.
hr = pConnEndpt->GetConnectedTo(&pConnHWDev);
// Query the connector in the adapter device for
// its IPart interface.
hr = pConnHWDev->QueryInterface(IID_IPart, (void**)&pPartConn);
// Use the connector's IPart interface to get the
// IDeviceTopology interface for the adapter device.
hr = pPartConn->Activate(CLSCTX_ALL, IID_IAudioAutoGainControl, (void**)&pAGC);
hr = pPartConn->GetControlInterfaceCount(&pCount);
hr = pPartConn->GetControlInterface(pCount - 1, &pControl);
hr = pControl->GetIID((GUID *)pIID);
//BOOL bEnabled = false;
hr = pAGC->SetEnabled(true, pIID);
【问题讨论】：