How to mute microphone in Windows 7 with C/C++?

Question

I made a program to mute microphone using WinAPI and it seems to work perfectly in Windows XP but doesn\'t do a thing in Windows 7. Is it possible to control microphone volu

Answer 1

You need to use the new audio APIs introduced by Windows Vista.

Here is an example.

*EDIT: Visual Studio 2015 (C++):

Usange:

// To 100%
ConsoleApplication3.exe -f 1

// To  0%
ConsoleApplication3.exe -f 0

// To 50%
ConsoleApplication3.exe -f 0.50

Code:

#include "stdafx.h"
#include 
#include 
#include 
#include 

void Usage()
{
    printf("Usage: \n");
    printf(" SetVolume [Reports the current volume]\n");
    printf(" SetVolume -d  [Sets the current default render device volume to the new volume]\n");
    printf(" SetVolume -f  [Sets the current default render device volume to the new volume]\n");

}
int _tmain(int argc, _TCHAR* argv[])
{
    HRESULT hr;
    bool decibels = false;
    bool scalar = false;
    double newVolume;
    if (argc != 3 && argc != 1)
    {
        Usage();
        return -1;
    }
    if (argc == 3)
    {
        if (argv[1][0] == '-')
        {
            if (argv[1][1] == 'f')
            {
                scalar = true;
            }
            else if (argv[1][1] == 'd')
            {
                decibels = true;
            }
        }
        else
        {
            Usage();
            return -1;
        }

        newVolume = _tstof(argv[2]);
    }

    // -------------------------
    CoInitialize(NULL);
    IMMDeviceEnumerator *deviceEnumerator = NULL;
    hr = CoCreateInstance(__uuidof(MMDeviceEnumerator), NULL, CLSCTX_INPROC_SERVER, __uuidof(IMMDeviceEnumerator), (LPVOID *)&deviceEnumerator);
    IMMDevice *defaultDevice = NULL;

    hr = deviceEnumerator->GetDefaultAudioEndpoint(eRender, eConsole, &defaultDevice);
    deviceEnumerator->Release();
    deviceEnumerator = NULL;

    IAudioEndpointVolume *endpointVolume = NULL;
    hr = defaultDevice->Activate(__uuidof(IAudioEndpointVolume), CLSCTX_INPROC_SERVER, NULL, (LPVOID *)&endpointVolume);
    defaultDevice->Release();
    defaultDevice = NULL;

    // -------------------------
    float currentVolume = 0;
    endpointVolume->GetMasterVolumeLevel(¤tVolume);
    printf("Current volume in dB is: %f\n", currentVolume);

    hr = endpointVolume->GetMasterVolumeLevelScalar(¤tVolume);
    printf("Current volume as a scalar is: %f\n", currentVolume);
    if (decibels)
    {
        hr = endpointVolume->SetMasterVolumeLevel((float)newVolume, NULL);
    }
    else if (scalar)
    {
        hr = endpointVolume->SetMasterVolumeLevelScalar((float)newVolume, NULL);
    }
    endpointVolume->Release();

    CoUninitialize();
    return 0;
}