#include <Windows.h>  
#include <Endpointvolume.h>  
#include <Mmdeviceapi.h>  
#include <conio.h>  
#pragma comment(lib, "Winmm.lib")  

IAudioEndpointVolume *m_pEndptVolCtrl;
IMMDeviceEnumerator *m_pEnumerator;
IMMDevice *m_pDevice;

int _tmain(int argc, _TCHAR* argv[])
{
    HRESULT hr = S_OK;
    int ret = 0;

    // Initialize COM component  
    hr = CoInitialize(NULL);

    if (FAILED(hr)) {
        printf("CoInitialize failed");
        return 1;
    }

    // Create instance for MMDevices...  
    hr = CoCreateInstance(__uuidof(MMDeviceEnumerator),
        NULL, CLSCTX_INPROC_SERVER,
        __uuidof(IMMDeviceEnumerator),
        (void**)&m_pEnumerator);
    if (FAILED(hr)) {
        printf("CoCreateInstance failed");
        return 1;
    }

    // Get default Andio Endpoint  
    hr = m_pEnumerator->GetDefaultAudioEndpoint(eRender, eConsole, &m_pDevice);
    if (FAILED(hr)) {
        printf("GetDefaultAudioEndpoint failed");
        return 1;
    }

    // Activate devices...  
    hr = m_pDevice->Activate(__uuidof(IAudioEndpointVolume),
        CLSCTX_ALL, NULL,
        (void**)&m_pEndptVolCtrl);
    if (FAILED(hr)) {
        printf("Activate failed");
        return 1;
    }

/*
    // Now you can operate it....  
    printf("SetMute...\n");
    hr = m_pEndptVolCtrl->SetMute(1, &GUID_NULL);
    getchar();

    printf("UnSetMute...\n");
    hr = m_pEndptVolCtrl->SetMute(0, &GUID_NULL);
    getchar();
*/
    UINT chan;
    hr = m_pEndptVolCtrl->GetChannelCount(&chan);
    if (FAILED(hr)) {
        printf("GetChannelCount fail\n");
        ret = 1;
    }
    printf("Set volume to Max...\nChannels: %d\n", chan);
    float vol;
    float vol1;
    float vol2;

    hr = m_pEndptVolCtrl->GetMasterVolumeLevelScalar(&vol);
    if (FAILED(hr)) {
        printf("GetMasterVolumeLevel fail\n");
        ret = 1;
    }
    hr = m_pEndptVolCtrl->GetChannelVolumeLevelScalar(0, &vol1);
    if (FAILED(hr)) {
        printf("GetChannelVolumeLevel fail\n");
        ret = 1;
    }
    hr = m_pEndptVolCtrl->GetChannelVolumeLevelScalar(1, &vol2);
    if (FAILED(hr)) {
        printf("GetChannelVolumeLevel fail\n");
        ret = 1;
    }
    printf("Before Master : %1.2f Left %1.2f  Right: %1.2f\n", vol, vol1, vol2);

    vol  = 1.0;
    vol1 = 1.0;
    vol2 = 1.0;

    printf("Set UnMute... ");
    hr = m_pEndptVolCtrl->SetMute(0, &GUID_NULL);
    if (FAILED(hr)) {
        printf("fail\n");
        ret = 1;
    }
    else {
        printf("ok\n");
    }
    
    printf("Set Master Volume Level... ");
    hr = m_pEndptVolCtrl->SetMasterVolumeLevelScalar(vol, &GUID_NULL);
    if (FAILED(hr)) {
        printf("fail\n");
        ret = 1;
    }
    else {
        printf("ok\n");
    }

    printf("Set Right  Volume Level... ");
    hr = m_pEndptVolCtrl->SetChannelVolumeLevelScalar(0, vol1, &GUID_NULL);
    if (FAILED(hr)) {
        printf("fail\n");
        ret = 1;
    }
    else {
        printf("ok\n");
    }
    
    printf("Set Left   Volume Level... ");
    hr = m_pEndptVolCtrl->SetChannelVolumeLevelScalar(1, vol2, &GUID_NULL);
    if (FAILED(hr)) {
        printf("fail\n");
        ret = 1;
    }
    else {
        printf("ok\n");
    }

    hr = m_pEndptVolCtrl->GetMasterVolumeLevelScalar(&vol);
    if (FAILED(hr)) {
        printf("GetMasterVolumeLevel fail\n");
        ret = 1;
    }
    hr = m_pEndptVolCtrl->GetChannelVolumeLevelScalar(0, &vol1);
    if (FAILED(hr)) {
        printf("GetChannelVolumeLevel fail\n");
        ret = 1;
    }
    hr = m_pEndptVolCtrl->GetChannelVolumeLevelScalar(1, &vol2);
    if (FAILED(hr)) {
        printf("GetChannelVolumeLevel fail\n");
        ret = 1;
    }
    printf("After Master : %1.2f Left %1.2f  Right: %1.2f\n", vol, vol1, vol2);

    CoUninitialize();
    return ret;
}