声音调节器

 

1.包含文件

#include <mmsystem.h>

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

2.定义变量

UINT m_nNumMixers;

HMIXER m_hMixer;

MIXERCAPS m_mxcaps;

CString m_strDstLineName,m_strVolumeControlName;

DWORD m_dwMinimum,m_dwMaximum;

DWORD m_dwVolumeControlID;

3.初始化:

BOOL CVolumeCtrl::amdInitialize()

{

m_nNumMixers = ::mixerGetNumDevs();

m_hMixer = NULL;

::ZeroMemory(&m_mxcaps,sizeof(MIXERCAPS));

if(m_nNumMixers != 0) {

  if(::mixerOpen(&m_hMixer,

      0,

      (DWORD)m_hParent->GetSafeHwnd(),

      NULL,

      MIXER_OBJECTF_MIXER|CALLBACK_WINDOW)

   != MMSYSERR_NOERROR) {

   return FALSE;

  }

  if(::mixerGetDevCaps((UINT)m_hMixer,&m_mxcaps,sizeof(MIXERCAPS))

   != MMSYSERR_NOERROR) {

   return FALSE;

  }

}

else {

  return FALSE;

}

return TRUE;

}

­

4.设置声音

BOOL CVolumeCtrl::SetVolume(DWORD dwVol)

{

if(m_hMixer == NULL ||

  m_strDstLineName.IsEmpty() ||

  m_strVolumeControlName.IsEmpty()

  ) {

  return FALSE;

}

MIXERCONTROLDETAILS_UNSIGNED mxcdVolume = {dwVol};

MIXERCONTROLDETAILS mxcd;

mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS);

mxcd.dwControlID = m_dwVolumeControlID;

mxcd.cChannels = 1;

mxcd.cMultipleItems = 0;

mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_UNSIGNED);

mxcd.paDetails = &mxcdVolume;

if(::mixerSetControlDetails((HMIXEROBJ)m_hMixer,

    &mxcd,

    MIXER_OBJECTF_HMIXER | MIXER_SETCONTROLDETAILSF_VALUE)

   != MMSYSERR_NOERROR) {

  return FALSE;

}

return TRUE;

}

­

5.获取声音:

BOOL CVolumeCtrl::GetVolume(DWORD &dwVol)

{

if(m_hMixer == NULL ||

  m_strDstLineName.IsEmpty() ||

  m_strVolumeControlName.IsEmpty()

  ) {

  return FALSE;

}

MIXERCONTROLDETAILS_UNSIGNED mxcdVolume = {dwVol};

MIXERCONTROLDETAILS mxcd;

mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS);

mxcd.dwControlID = m_dwVolumeControlID;

mxcd.cChannels = 1;

mxcd.cMultipleItems = 0;

mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_UNSIGNED);

mxcd.paDetails = &mxcdVolume;

if(::mixerGetControlDetails((HMIXEROBJ)m_hMixer,

    &mxcd,

    MIXER_OBJECTF_HMIXER | MIXER_SETCONTROLDETAILSF_VALUE)

   != MMSYSERR_NOERROR) {

  return FALSE;

}

dwVol = mxcdVolume.dwValue;

return TRUE;

}

6.

­

BOOL CVolumeCtrl::amdGetVolumeControl()

{

m_strDstLineName.Empty();

m_strVolumeControlName.Empty();

if(m_hMixer == NULL) {

  return FALSE;

}

MIXERLINE mxl;

mxl.cbStruct = sizeof(MIXERLINE);

mxl.dwComponentType = MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;

if(::mixerGetLineInfo((HMIXEROBJ)m_hMixer,

    &mxl,

    MIXER_OBJECTF_HMIXER |

    MIXER_GETLINEINFOF_COMPONENTTYPE)

   != MMSYSERR_NOERROR) {

  return FALSE;

}

MIXERCONTROL mxc;

MIXERLINECONTROLS mxlc;

mxlc.cbStruct = sizeof(MIXERLINECONTROLS);

mxlc.dwLineID = mxl.dwLineID;

mxlc.dwControlType = MIXERCONTROL_CONTROLTYPE_VOLUME;

mxlc.cControls = 1;

mxlc.cbmxctrl = sizeof(MIXERCONTROL);

mxlc.pamxctrl = &mxc;

if(::mixerGetLineControls((HMIXEROBJ)m_hMixer,

    &mxlc,

    MIXER_OBJECTF_HMIXER |

    MIXER_GETLINECONTROLSF_ONEBYTYPE)

   != MMSYSERR_NOERROR) {

  return FALSE;

}

m_strDstLineName = mxl.szName;

m_strVolumeControlName = mxc.szName;

m_dwMinimum = mxc.Bounds.dwMinimum;

m_dwMaximum = mxc.Bounds.dwMaximum;

m_dwVolumeControlID = mxc.dwControlID;

return TRUE;

}