通过API选择声卡输入通道

网上此类贴子很多，工作原理就不用介绍了，请看代码：

// AudioInputChannel.cpp : 定义控制台应用程序的入口点。

//

#include "stdafx.h"

#include <stdio.h>

#include <stdlib.h>

#include <tchar.h>

#include <windows.h>

#ifndef _INC_MMSYSTEM

#include <mmsystem.h>

#pragma comment(lib, "winmm.lib")

#endif

void PrintMixerLinesInfo(void);

bool ActiveMixerInputChannel(UINT, UINT);

int _tmain(int argc, _TCHAR* argv[])

{

UINT di, li;

PrintMixerLinesInfo ();

_tcprintf( TEXT("输入设备编号与录音通道编号(例：0 1)") );

_tscanf ( TEXT("%d %d"), &di, &li );

if ( !ActiveMixerInputChannel ( di, li ) ){

_tcprintf( TEXT("设置失败！/n") );

} else {

_tcprintf( TEXT("设置成功！/n") );

PrintMixerLinesInfo ();

}

system("pause");

return 0;

}

void PrintMixerLinesInfo(void)

{

MIXERCAPS mxcaps = {0};

HMIXER hMixer = NULL;

for ( UINT i = 0; i < mixerGetNumDevs (); i++ ){

if ( MMSYSERR_NOERROR != mixerGetDevCaps ( i, &mxcaps, sizeof ( MIXERCAPS ) ) ){ continue; }

if ( MMSYSERR_NOERROR != mixerOpen ( &hMixer, i, NULL, NULL, 0 ) ){ continue; }

MIXERLINE mxl = { sizeof ( MIXERLINE ), 0, 0, 0, 0, 0, MIXERLINE_COMPONENTTYPE_DST_WAVEIN, 0};

if ( MMSYSERR_NOERROR != mixerGetLineInfo ( (HMIXEROBJ)hMixer, &mxl, MIXER_GETLINEINFOF_COMPONENTTYPE ) ){

mixerClose ( hMixer );

continue;

}

_tcprintf( TEXT("%d: %s /t[%s]/n"), i, mxcaps.szPname, mxl.szName );

MIXERCONTROL mxc = { sizeof ( MIXERCONTROL ), 0 };

MIXERLINECONTROLS mxlc = { sizeof ( MIXERLINECONTROLS ), mxl.dwLineID, MIXERCONTROL_CONTROLTYPE_MIXER, 1, mxc.cbStruct, &mxc };

if ( MMSYSERR_NOERROR != mixerGetLineControls ( (HMIXEROBJ)hMixer, &mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE ) ){

mxlc.dwControlType = MIXERCONTROL_CONTROLTYPE_MUX;

if ( MMSYSERR_NOERROR != mixerGetLineControls ( (HMIXEROBJ)hMixer, &mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE ) ){

mixerClose ( hMixer );

continue;

}

}

if ( mxc.cMultipleItems == 0 ){

mixerClose ( hMixer );

continue;

}

MIXERCONTROLDETAILS mxcd = { sizeof ( MIXERCONTROLDETAILS ), mxc.dwControlID, 1, 0 };

PMIXERCONTROLDETAILS_LISTTEXT mxcdlts = (PMIXERCONTROLDETAILS_LISTTEXT)malloc ( sizeof ( MIXERCONTROLDETAILS_LISTTEXT ) * mxc.cMultipleItems );

mxcd.cbDetails = sizeof ( MIXERCONTROLDETAILS_LISTTEXT );

mxcd.cMultipleItems = mxc.cMultipleItems;

mxcd.paDetails = mxcdlts;

if ( MMSYSERR_NOERROR != mixerGetControlDetails ( (HMIXEROBJ)hMixer, &mxcd, MIXER_GETCONTROLDETAILSF_LISTTEXT ) ){

free ( mxcdlts );

mixerClose ( hMixer );

continue;

}

PMIXERCONTROLDETAILS_BOOLEAN mxcdbls = (PMIXERCONTROLDETAILS_BOOLEAN)malloc ( sizeof ( MIXERCONTROLDETAILS_BOOLEAN ) * mxc.cMultipleItems );

mxcd.cbDetails = sizeof ( MIXERCONTROLDETAILS_BOOLEAN );

mxcd.cMultipleItems = mxc.cMultipleItems;

mxcd.paDetails = mxcdbls;

if ( MMSYSERR_NOERROR != mixerGetControlDetails ( (HMIXEROBJ)hMixer, &mxcd, MIXER_GETCONTROLDETAILSF_VALUE ) ){

free ( mxcdbls );

mixerClose ( hMixer );

continue;

}

DWORD dwConnections = mxl.cConnections;

DWORD dwDestination = mxl.dwDestination;

for ( DWORD j = 0; j < dwConnections; j++ ){

mxl.dwDestination = dwDestination;

mxl.dwSource = j;

if ( MMSYSERR_NOERROR != mixerGetLineInfo ( (HMIXEROBJ)hMixer, &mxl, MIXER_GETLINEINFOF_DESTINATION | MIXER_GETLINEINFOF_SOURCE ) ){ continue; }

for ( DWORD k = 0; k < mxc.cMultipleItems; k++ ){

if ( mxcdlts[k].dwParam1 == mxl.dwLineID ){

_tcprintf( TEXT("/t%d %s /t%s/n"), j, mxl.szName, mxcdbls[k].fValue ? TEXT("Enabled") : TEXT("Disabled") );

break;

}

}

}

_tcprintf( TEXT("/n") );

free ( mxcdbls );

free ( mxcdlts );

mixerClose ( hMixer );

}

}

bool ActiveMixerInputChannel(UINT nMixerDeviceIndex, UINT nMixerLineIndex)

{

bool result = false;

HMIXER hMixer = NULL;

MIXERCONTROL mxc = { sizeof ( MIXERCONTROL ), 0 };

MIXERLINE mxl = { sizeof ( MIXERLINE ), 0, 0, 0, 0, 0, MIXERLINE_COMPONENTTYPE_DST_WAVEIN, 0};

if ( MMSYSERR_NOERROR != mixerOpen ( &hMixer, nMixerDeviceIndex, NULL, NULL, 0 ) ){ return false; }

if ( MMSYSERR_NOERROR != mixerGetLineInfo ( (HMIXEROBJ)hMixer, &mxl, MIXER_GETLINEINFOF_COMPONENTTYPE ) ){

mixerClose ( hMixer );

return false;

}

MIXERLINECONTROLS mxlc = { sizeof ( MIXERLINECONTROLS ), mxl.dwLineID, MIXERCONTROL_CONTROLTYPE_MIXER, 1, mxc.cbStruct, &mxc };

mxl.dwSource = nMixerLineIndex;

if ( MMSYSERR_NOERROR != mixerGetLineInfo ( (HMIXEROBJ)hMixer, &mxl, MIXER_GETLINEINFOF_DESTINATION | MIXER_GETLINEINFOF_SOURCE ) ){

mixerClose ( hMixer );

return false;

}

if ( MMSYSERR_NOERROR != mixerGetLineControls ( (HMIXEROBJ)hMixer, &mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE ) ){

mxlc.dwControlType = MIXERCONTROL_CONTROLTYPE_MUX;

if ( MMSYSERR_NOERROR != mixerGetLineControls ( (HMIXEROBJ)hMixer, &mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE ) ){

mixerClose ( hMixer );

return false;

}

}

if ( mxc.cMultipleItems == 0 ){ mixerClose ( hMixer ); return false; }

PMIXERCONTROLDETAILS_BOOLEAN mxcdbls = (PMIXERCONTROLDETAILS_BOOLEAN)malloc ( sizeof ( MIXERCONTROLDETAILS_BOOLEAN ) * mxc.cMultipleItems );

PMIXERCONTROLDETAILS_LISTTEXT mxcdlts = (PMIXERCONTROLDETAILS_LISTTEXT)malloc ( sizeof ( MIXERCONTROLDETAILS_LISTTEXT ) * mxc.cMultipleItems );

MIXERCONTROLDETAILS mxcd = { sizeof ( MIXERCONTROLDETAILS ), mxc.dwControlID, 1, (HWND)mxc.cMultipleItems, sizeof ( MIXERCONTROLDETAILS_LISTTEXT ), mxcdlts };

if ( MMSYSERR_NOERROR == mixerGetControlDetails ( (HMIXEROBJ)hMixer, &mxcd, MIXER_GETCONTROLDETAILSF_LISTTEXT ) ){

memset ( mxcdbls, 0, sizeof ( MIXERCONTROLDETAILS_BOOLEAN ) * mxc.cMultipleItems );

for ( DWORD i = 0; i < mxc.cMultipleItems; i++ ){

if ( mxcdlts[i].dwParam1 == mxl.dwLineID ){

mxcdbls[i].fValue = 1;

mxcd.paDetails = mxcdbls;

mxcd.cbDetails = sizeof ( MIXERCONTROLDETAILS_BOOLEAN );

result = (MMSYSERR_NOERROR == mixerSetControlDetails ( (HMIXEROBJ)hMixer, &mxcd, MIXER_SETCONTROLDETAILSF_VALUE ) ); break;

}

}

}

free ( mxcdbls );

free ( mxcdlts );

mixerClose ( hMixer );

return result;

}