混音器DEMO

#include "stdafx.h"

void SetAudio()
{
    MMRESULT mmResult;
    HMIXER hMixer;
    MIXERCAPS mixercaps;

    MIXERLINE mixerline;
    memset(&mixerline,0,sizeof(MIXERLINE));
    mixerline.cbStruct = sizeof(MIXERLINE);

    MIXERLINECONTROLS mlc;
    memset(&mlc,0,sizeof(MIXERLINECONTROLS));
    mlc.cbStruct = sizeof(MIXERLINECONTROLS);

    MIXERCONTROL mc;
    memset(&mc,0,sizeof(MIXERCONTROL));
    mc.cbStruct = sizeof(MIXERCONTROL);

    DWORD dwStereoSelControlID;
    DWORD dwTotalItems;

    BOOL bFinished = FALSE;

    UINT uNum = mixerGetNumDevs();
    for ( int i = 0; i < uNum; i++ )
    {
        mmResult = mixerOpen(&hMixer,i,0,0,MIXER_OBJECTF_MIXER);
        mmResult = mixerGetDevCaps(i,&mixercaps,sizeof(MIXERCAPS));
        for ( int j = 0; j < mixercaps.cDestinations; j++ )
        {
            mixerline.dwDestination = j;
            mmResult = mixerGetLineInfo((HMIXEROBJ)hMixer,&mixerline,MIXER_GETLINEINFOF_DESTINATION);
            if ( mixerline.dwComponentType == MIXERLINE_COMPONENTTYPE_DST_WAVEIN && mixerline.dwLineID == 4294901761 )
            {
                mlc.cControls = 1;
                mlc.cbmxctrl = sizeof(MIXERCONTROL);                  
                mlc.pamxctrl = &mc;
                mlc.dwLineID = mixerline.dwLineID;
                mlc.dwControlType = MIXERCONTROL_CONTROLTYPE_MUX;
                mmResult = mixerGetLineControls((HMIXEROBJ)hMixer,&mlc,MIXER_OBJECTF_HMIXER | MIXER_GETLINECONTROLSF_ONEBYTYPE);

                dwStereoSelControlID = mc.dwControlID;
                dwTotalItems = mc.cMultipleItems;

                MIXERLINE line;
                memset(&line,0,sizeof(MIXERLINE));
                line.cbStruct = sizeof(MIXERLINE);
                line.dwDestination = j;

                MIXERCONTROLDETAILS_BOOLEAN *pmxcdMute = (MIXERCONTROLDETAILS_BOOLEAN*)malloc(sizeof(MIXERCONTROLDETAILS_BOOLEAN)*dwTotalItems);
                for ( int i = 0; i < dwTotalItems; i++ )
                { 
                    line.dwSource = i;
                    mmResult = mixerGetLineInfo((HMIXEROBJ)hMixer,&line,MIXER_GETLINEINFOF_SOURCE);                         
                    if ( line.dwComponentType == MIXERLINE_COMPONENTTYPE_SRC_ANALOG && line.dwLineID == 65537 )                  
                    {
                        int nIndex = dwTotalItems-1-i;
                        for ( int k = 0; k < dwTotalItems; k++ )
                        {
                            pmxcdMute[k].fValue = FALSE;
                        }
                        pmxcdMute[nIndex].fValue = TRUE;
                    }
                }     

                MIXERCONTROLDETAILS mixercontroldetails;
                memset(&mixercontroldetails,0,sizeof(MIXERCONTROLDETAILS));

                mixercontroldetails.cbStruct = sizeof(MIXERCONTROLDETAILS);
                mixercontroldetails.cbDetails = sizeof(MIXERCONTROLDETAILS_BOOLEAN);
                mixercontroldetails.cChannels = 1;             
                mixercontroldetails.paDetails = pmxcdMute;
                mixercontroldetails.dwControlID = dwStereoSelControlID;
                mixercontroldetails.cMultipleItems = dwTotalItems;
              
                mmResult = mixerSetControlDetails((HMIXEROBJ)hMixer,&mixercontroldetails,MIXER_SETCONTROLDETAILSF_VALUE | MIXER_OBJECTF_HMIXER);
                free(pmxcdMute);
           
                DWORD dwConnections = mixerline.cConnections;
                for ( int count = 0; count < dwConnections; count++ )
                {
                    mixerline.dwSource = count;
                    mmResult = mixerGetLineInfo((HMIXEROBJ)hMixer,&mixerline,MIXER_OBJECTF_HMIXER | MIXER_GETLINEINFOF_SOURCE);
                    if ( mixerline.dwComponentType == MIXERLINE_COMPONENTTYPE_SRC_ANALOG && mixerline.dwLineID == 65537 )
                    {
                        DWORD dwChannel = mixerline.cChannels;

                        mlc.cControls = 1;
                        mlc.cbmxctrl = sizeof(MIXERCONTROL);                  
                        mlc.pamxctrl = &mc;
                        mlc.dwLineID = mixerline.dwLineID;
                        mlc.dwControlType = MIXERCONTROL_CONTROLTYPE_VOLUME;
                        mmResult = mixerGetLineControls((HMIXEROBJ)hMixer,&mlc,MIXER_OBJECTF_HMIXER | MIXER_GETLINECONTROLSF_ONEBYTYPE);

                        MIXERCONTROLDETAILS_BOOLEAN* pControlDetail_BOOL = (MIXERCONTROLDETAILS_BOOLEAN*)malloc(dwChannel*sizeof(MIXERCONTROLDETAILS_BOOLEAN));
                        if ( !pControlDetail_BOOL )
                            return;
                        for ( int i = 0; i < dwChannel; i++ )
                        {
                            pControlDetail_BOOL[i].fValue = 65535;
                        }

                        MIXERCONTROLDETAILS mixercontroldetails;
                        memset(&mixercontroldetails,0,sizeof(MIXERCONTROLDETAILS));

                        mixercontroldetails.cbStruct = sizeof(MIXERCONTROLDETAILS);
                        mixercontroldetails.cbDetails = sizeof(MIXERCONTROLDETAILS_BOOLEAN);
                        mixercontroldetails.cChannels = 1;
                        mixercontroldetails.cMultipleItems = 0;
                        mixercontroldetails.paDetails = &pControlDetail_BOOL[0];
                        mixercontroldetails.dwControlID = mc.dwControlID;

                        mmResult = mixerSetControlDetails((HMIXEROBJ)hMixer,&mixercontroldetails,MIXER_SETCONTROLDETAILSF_VALUE | MIXER_OBJECTF_HMIXER);
                        free(pControlDetail_BOOL);

                        bFinished = TRUE;

                        break;
                    }
                }
                break;
            }
        }
        mixerClose(hMixer);
        if ( bFinished )
            break;
    }
}

int _tmain(int argc, _TCHAR* argv[])
{
    SetAudio();
    return 0;
}