◆◆◆◆ 怎样才可以查询windows当前音量？◆◆◆◆

[skymartin]

比如我现在放一首mp3，电脑的音量肯定时刻在变化，我怎么才能够查询出当前的音量呢？

我说的音量不是只右下角那个黄色小喇叭可以调节的那个音量，那个音量如果你不去动他，基本上是固定不变的。

windows有没有提供什么api完成上面的功能的呢？

[kingzai]

MMRESULT mmr;
HMIXER m_hmx;
MIXERCAPS m_mxcaps;
MIXERLINE m_mxl;
MIXERLINECONTROLS m_mxlc;
MIXERCONTROL m_mxctrl;
ULONG cConnections,v;
mmr = mixerGetDevCaps(0, &m_mxcaps, sizeof(m_mxcaps));
if (MMSYSERR_NOERROR != mmr)
{
MessageBox("Can't Get Device Caps.");
return TRUE;
}
mmr = mixerOpen(&m_hmx, 0, (DWORD)m_hWnd, 0L, CALLBACK_WINDOW);
if (MMSYSERR_NOERROR != mmr)
{
MessageBox("Can't Open Mixer Device.");
return TRUE;
}
m_mxl.cbStruct = sizeof(m_mxl);
m_mxl.dwDestination = 0;
mmr = mixerGetLineInfo((HMIXEROBJ)m_hmx, &m_mxl, MIXER_GETLINEINFOF_DESTINATION);
if (MMSYSERR_NOERROR != mmr)
{
MessageBox("Can't Get Mixer Device Line Info For Volume Controls");
return TRUE;
}
cConnections=m_mxl.cConnections;
m_mxlc.cbStruct = sizeof(m_mxlc);
m_mxlc.dwLineID = m_mxl.dwLineID;
m_mxlc.cControls = m_mxl.cControls;
m_mxlc.cbmxctrl = sizeof(m_mxctrl);
m_mxlc.dwControlType = MIXERCONTROL_CONTROLTYPE_VOLUME;
m_mxlc.pamxctrl = &m_mxctrl;
mmr = mixerGetLineControls((HMIXEROBJ)m_hmx, &m_mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE);
if (MMSYSERR_NOERROR != mmr)
{
MessageBox("Can't Get Line Info For Volume Controls");
return TRUE;
}

[skymartin]

音量值是保存在m_mxlc中吗？
但是我MSDN查了一下，没有发现m_mxlc中那个成员表示音量的.

[kingzai]

m_mxlc 是MIXERLINECONTROLS变量，你查询MIXERLINECONTROLS结构

[skymartin]

是放在MIXERLINECONTROLS的LPMIXERCONTROL pamxctrl成员中吗?

pamxctrl是一个MIXERCONTROL结构,但是MIXERCONTROL中也没有发现有音量的属性啊.

还请教大侠~~

[skymartin]

好像出了点问题.

mmr = mixerOpen(&m_hmx, 0, (DWORD)m_hWnd, 0L, CALLBACK_WINDOW);
一句中m_hWnd是必须的吗? 我最终的程序是控制台程序,没有窗口怎么办?

还有m_mxctrl.Metrics.cbCustomData我估计就是音量了,但是为什么无论我放什么mp3, 其值总为192啊, 不明白为什么~~~

[kingzai]

MIXERCONTROLDETAILS mxcd;
MIXERCONTROLDETAILS_UNSIGNED vol; vol.dwValue=0;
mxcd.hwndOwner = 0;
mxcd.cbStruct = sizeof(mxcd);
mxcd.dwControlID = mxc->dwControlID;
mxcd.cbDetails = sizeof(vol);
mxcd.paDetails = &vol;
mxcd.cChannels = 1;
if(mixerGetControlDetails((HMIXEROBJ)hmixer, &mxcd, MIXER_OBJECTF_HMIXER|MIXER_GETCONTROLDETAILSF_VALUE))
return -1;
return vol.dwValue;
http://search.csdn.net/Expert/topic/1431/1431476.xml?temp=.8853113

[skymartin]

试过了, 的确可以, 但是我要的不是右下角黄色喇叭中设置的那个音量啊:(

换个说法问法把: 播mp3时, 怎么可以得到声卡中当前声音波形的振幅.

当然不同频率有不同频率的波形.

请问大侠有其他办法吗? 不过真的很谢谢您^_^

[kingzai]

用低级音频函数。
waveInGetNumDevs();
waveInGetDevCaps (0, &m_WaveInDevCaps, sizeof(WAVEINCAPS));}
WaveInitFormat(1/* mono*/,m_WaveInSampleRate /* khz */,16 /* bits */);
waveInOpen( &m_WaveIn,0, &m_WaveFormat,(DWORD)
waveInPrepareHeader( m_WaveIn, &m_WaveHeader, sizeof(WAVEHDR) ); }
waveInAddBuffer( m_WaveIn, &m_WaveHeader, sizeof(WAVEHDR) );
waveInStart( m_WaveIn );
www.csdn.net/develop/Read_Article.asp?Id=9780

[skymartin]

谢谢大侠们,正在尝试中^_^

[oyljerry]

waveOutGetVolume

[NowCan]

用低级音频函数。
waveInGetNumDevs();
waveInGetDevCaps (0, &m_WaveInDevCaps, sizeof(WAVEINCAPS));}
WaveInitFormat(1/* mono*/,m_WaveInSampleRate /* khz */,16 /* bits */);
waveInOpen( &m_WaveIn,0, &m_WaveFormat,(DWORD)
waveInPrepareHeader( m_WaveIn, &m_WaveHeader, sizeof(WAVEHDR) ); }
waveInAddBuffer( m_WaveIn, &m_WaveHeader, sizeof(WAVEHDR) );
waveInStart( m_WaveIn );
www.csdn.net/develop/Read_Article.asp?Id=9780

除此之外，还要将录音源设置为“Mixer Out”或者是“Wave Out”

[yszmax]

gz

[mybios]

成功了告诉一声！我也想用。