IAudioEndpointVolume

AudioDeviceWindowsCore

源码分析

H:\webrtc-20210315\webrtc-20210315\webrtc\webrtc-checkout\src\media\engine\adm_helpers.cc
void Init(AudioDeviceModule* adm) 方法

webrtc::adm_helpers::Init

void Init(AudioDeviceModule* adm) {
***
 // Recording device.
  {
    if (adm->SetRecordingDevice(AUDIO_DEVICE_ID) != 0) {
      RTC_LOG(LS_ERROR) << "Unable to set recording device.";
      return;
    }
    if (adm->InitMicrophone() != 0) {
      RTC_LOG(LS_ERROR) << "Unable to access microphone.";
    }
    // Set number of channels
    bool available = false;
    if (adm->StereoRecordingIsAvailable(&available) != 0) {
      RTC_LOG(LS_ERROR) << "Failed to query stereo recording.";
    }
    if (adm->SetStereoRecording(available) != 0) {
      RTC_LOG(LS_ERROR) << "Failed to set stereo recording mode.";
    }
  }
}
adm->InitMicrophone()
->
AudioDeviceModuleImpl::InitMicrophone
->
AudioDeviceWindowsCore::InitMicrophone
->
AudioDeviceWindowsCore::InitMicrophoneLocked

AudioDeviceWindowsCore::InitMicrophoneLocked

int32_t AudioDeviceWindowsCore::InitMicrophoneLocked() {
 **
  if (_usingInputDeviceIndex) {
**
  } else {
    ERole role;
    (_inputDevice == AudioDeviceModule::kDefaultDevice)
        ? role = eConsole
        : role = eCommunications;
    // Refresh the selected capture endpoint device using role
    ret = _GetDefaultDevice(eCapture, role, &_ptrDeviceIn);
  }
**
  SAFE_RELEASE(_ptrCaptureVolume);
  ret = _ptrDeviceIn->Activate(__uuidof(IAudioEndpointVolume), CLSCTX_ALL, NULL,
                               reinterpret_cast<void**>(&_ptrCaptureVolume));
  if (ret != 0 || _ptrCaptureVolume == NULL) {
    RTC_LOG(LS_ERROR) << "failed to initialize the capture volume";
    SAFE_RELEASE(_ptrCaptureVolume);
    return -1;
  }
  _microphoneIsInitialized = true;
  return 0;
}