WASAPI在线捕获静态噪声

Question

它似乎只能捕获笔记本电脑和PC上的静态噪声...在我的PC上，录音设备（Stereo Mix-Realtek High Definiton Audio），在笔记本电脑上，我使用录音设备Stereo Mix（Realtek Audio）。我可以修改WAVEFORMATEX并更改驱动程序格式，但仍然只能听到不同种类的大声静态噪声或根本没有声音（00 FF数据字节组合）。

HRESULT InitAudio() {
    HRESULT hr = E_FAIL;
    REFERENCE_TIME hnsRequestedDuration;
    REFERENCE_TIME hnsActualDuration;
    UINT32 bufferFrameCount;
    IMMDeviceEnumerator *pEnumerator = NULL;
    IMMDeviceCollection* pIMMDeviceCollection = NULL;
    IMMDevice *pDevice = NULL;

    _AudioSamplesReadyEvent = CreateEventEx(NULL, NULL, 0, EVENT_MODIFY_STATE | SYNCHRONIZE);
    _ShutdownEvent = CreateEventEx(NULL, NULL, 0, EVENT_MODIFY_STATE | SYNCHRONIZE);

    WAVEFORMATEX                wfx =
  {WAVE_FORMAT_PCM, wavFile.num_channels, wavFile.sample_rate, wavFile.byte_rate, wavFile.sample_alignment, wavFile.bit_depth, 0};

    hr = CoCreateInstance(
           CLSID_MMDeviceEnumerator, NULL,
           CLSCTX_ALL, IID_IMMDeviceEnumerator,
           (void**)&pEnumerator);

    hr = pEnumerator->EnumAudioEndpoints(eCapture,DEVICE_STATE_ACTIVE,&pIMMDeviceCollection);
    hr = pIMMDeviceCollection->Item(0, &pDevice);

    hr = pDevice->Activate(
                    IID_IAudioClient, CLSCTX_ALL,
                    NULL, (void**)&pAudioClient);

    hr = pAudioClient->GetDevicePeriod(NULL, &hnsRequestedDuration);
    hr = pAudioClient->Initialize(
                         AUDCLNT_SHAREMODE_SHARED,
                         AUDCLNT_STREAMFLAGS_EVENTCALLBACK | AUDCLNT_STREAMFLAGS_NOPERSIST,
                         hnsRequestedDuration,
                         0,
                         &wfx,
                         NULL);


    hr = pAudioClient->SetEventHandle(_AudioSamplesReadyEvent);
    if (FAILED(hr)) MessageBox(NULL,TEXT("Unable to set event handle!"), TEXT("Error"), MB_OK);

    hr = pAudioClient->GetService(
                         IID_IAudioCaptureClient,
                         (void**)&pCaptureClient);

    ProcessSoundThread = CreateThread(NULL, 0, ProcessSound, 0, 0, NULL);

    hr = pAudioClient->Start();  // Start recording.

    return hr;
}

DWORD WINAPI ProcessSound(void* arg) {
    UINT32 numFramesAvailable;
    UINT32 packetLength = 0;
    UINT32 dataSize = 0;
    BYTE *pData;
    DWORD  flags;
    HRESULT hr;
    UINT dwDataWrote;

    HANDLE waitArray[2] = { _AudioSamplesReadyEvent, _ShutdownEvent};
    HANDLE mmcssHandle = NULL;
    DWORD mmcssTaskIndex = 0;

    hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
    if (FAILED(hr)) MessageBox(NULL,TEXT("Unable to initialize COM in render thread!"), TEXT("Error"), MB_OK);

    mmcssHandle = AvSetMmThreadCharacteristics("Audio", &mmcssTaskIndex);
    if(mmcssHandle == NULL) MessageBox(NULL,TEXT("Unable to enable MMCSS on capture thread!"), TEXT("Error"), MB_OK);

    while(captureSound) {
        DWORD waitResult = WaitForMultipleObjects(2, waitArray, FALSE, INFINITE);
        switch (waitResult)
            {
            case WAIT_OBJECT_0 + 0:
                hr = pCaptureClient->GetBuffer(&pData,&numFramesAvailable,&flags,NULL,NULL);
                if(hr != AUDCLNT_S_BUFFER_EMPTY) {
                    dataSize = numFramesAvailable * wavFile.sample_alignment; // wavFile.sample_alignment = frameSize = num_channels * (pWav->bit_depth)/8
                    if (FAILED( addWavData(&wavFile, pData, dataSize, &dwDataWrote)))
                        MessageBox(NULL,TEXT("Error writting the data!"), TEXT("Error"), MB_OK); 
                    totalData += dataSize;
                }
                pCaptureClient->ReleaseBuffer(numFramesAvailable);
                break;
            case WAIT_OBJECT_0 + 1:   
                captureSound = false;
                break;
            }`
    }
    return 0;
}