在 C# 中获取主音量

Question

我需要获得输出到声卡的当前音量。

任何想法如何？

Answer 1

您可以使用 Vista 和 Win 7 中 CoreAudio API 中的IAudioMeterInformation获取这些值。

NAudio中提供了托管包装器（从 MMDevice 获取 AudioMeterInformation）。

Answer 2

    static int PlayerVolume()
    {
        RecordPlayer rp = new RecordPlayer();
        rp.PlayerID = -1;
        int playerVolume = rp.PlayerVolume;
        return playerVolume;
    }

来自c#文章中修改后的麦克风音量

Answer 3

我在开发一个（尚未发布......）应用程序时解决了这个问题，该应用程序在没有其他声音时启动某种“电梯音乐”。

按照 Mark Heath 给出的精彩提示，我得到了我想要的：

 using NAudio.CoreAudioApi; 
 MMDeviceEnumerator devEnum = new MMDeviceEnumerator();
 MMDevice defaultDevice = devEnum.GetDefaultAudioEndpoint(DataFlow.Render, Role.Multimedia);
 string currVolume = "MasterPeakVolume : " + defaultDevice.AudioMeterInformation.MasterPeakValue.ToString();

Answer 4

在 MSDN 信息中查找：

• IMMDeviceCollection、IMMDevice 和 IAudioEndpointVolume（仅限 Windows Vista、Windows 7）。
• mixerGetNumDevs、mixerGetLineControls、...

这是“常见”信息。 C# 可能有更方便的方法（我不知道）。

Answer 5

也许 winmm.dll 可以帮助您：

来自 EDDYKT (VB)：

Private Const HIGHEST_VOLUME_SETTING = 100 '%
Private Const AUX_MAPPER = -1&
Private Const MAXPNAMELEN = 32
Private Const AUXCAPS_CDAUDIO = 1   '  audio from internal CD-ROM drive
Private Const AUXCAPS_AUXIN = 2   '  audio from auxiliary input jacks
Private Const AUXCAPS_VOLUME = &H1          '  supports volume control
Private Const AUXCAPS_LRVOLUME = &H2          '  separate left-right volume control
Private Const MMSYSERR_NOERROR = 0
Private Const MMSYSERR_BASE = 0
Private Const MMSYSERR_BADDEVICEID = (MMSYSERR_BASE + 2)
Private Type AUXCAPS
       wMid As Integer
       wPid As Integer
       vDriverVersion As Long
       szPname As String * MAXPNAMELEN
       wTechnology As Integer
       dwSupport As Long
End Type
Private Type VolumeSetting
    LeftVol As Integer
    RightVol As Integer
End Type
Private Declare Function auxGetNumDevs Lib "winmm.dll" () As Long
Private Declare Function auxGetDevCaps Lib "winmm.dll" Alias "auxGetDevCapsA" (ByVal uDeviceID As Long, lpCaps As AUXCAPS, ByVal uSize As Long) As Long
Private Declare Function auxSetVolume Lib "winmm.dll" (ByVal uDeviceID As Long, ByVal dwVolume As Long) As Long
Private Declare Function auxGetVolume Lib "winmm.dll" (ByVal uDeviceID As Long, ByRef lpdwVolume As VolumeSetting) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (hpvDest As Any, hpvSource As Any, ByVal cbCopy As Long)
Private Function nSigned(ByVal lUnsignedInt As Long) As Integer
    Dim nReturnVal As Integer                          ' Return value from Function
    If lUnsignedInt > 65535 Or lUnsignedInt < 0 Then
        MsgBox "Error in conversion from Unsigned to nSigned Integer"
        nSignedInt = 0
        Exit Function
    End If
    If lUnsignedInt > 32767 Then
        nReturnVal = lUnsignedInt - 65536
    Else
        nReturnVal = lUnsignedInt
    End If
    nSigned = nReturnVal
End Function
Private Function lUnsigned(ByVal nSignedInt As Integer) As Long
    Dim lReturnVal As Long                          ' Return value from Function
    If nSignedInt < 0 Then
        lReturnVal = nSignedInt + 65536
    Else
        lReturnVal = nSignedInt
    End If
    If lReturnVal > 65535 Or lReturnVal < 0 Then
        MsgBox "Error in conversion from nSigned to Unsigned Integer"
        lReturnVal = 0
    End If
    lUnsigned = lReturnVal
End Function
Private Function lSetVolume(ByRef lLeftVol As Long, ByRef lRightVol As Long, lDeviceID As Long) As Long
    Dim Volume As VolumeSetting, lBothVolumes As Long
    Volume.LeftVol = nSigned(lLeftVol * 65535 / HIGHEST_VOLUME_SETTING)
    Volume.RightVol = nSigned(lRightVol * 65535 / HIGHEST_VOLUME_SETTING)
    'copy our Volume-variable to a long
    CopyMemory lBothVolumes, Volume.LeftVol, Len(Volume)
    'call the SetVolume-function
    lSetVolume = auxSetVolume(lDeviceID, lBothVolumes)
End Function
Private Sub Form_Load()
    'KPD-Team 2000
    'URL: http://www.allapi.net/
    'E-Mail: KPDTeam@Allapi.net
    Dim Volume As VolumeSetting, Cnt As Long, AC As AUXCAPS
    'set the output to a persistent graphic
    Me.AutoRedraw = True
    'loop through all the devices
    For Cnt = 0 To auxGetNumDevs - 1 'auxGetNumDevs is zero-based
        'get the volume
        auxGetVolume Cnt, Volume
        'get the device capabilities
        auxGetDevCaps Cnt, AC, Len(AC)
        'print the name on the form
        Me.Print "Device #" + Str$(Cnt + 1) + ":  " + Left(AC.szPname, InStr(AC.szPname, vbNullChar) - 1)
        'print the left- and right volume on the form
        Me.Print "Left volume:" + Str$(HIGHEST_VOLUME_SETTING * lUnsigned(Volume.LeftVol) / 65535)
        Me.Print "Right volume:" + Str$(HIGHEST_VOLUME_SETTING * lUnsigned(Volume.RightVol) / 65535)
        'set the left- and right-volume to 50%
        lSetVolume 50, 50, Cnt
        Me.Print "Both volumes now set to 50%"
        'empty line
        Me.Print
    Next
End Sub

或者也许这个： http : //blackbeltvb.com/index.htm?free/mcisamp.htm

Answer 6

从代码项目中查看此代码： 使用 DirectX 的 LED 风格音量计

本文用作我创建的名为 AnalogSignalMeter 的 UserControl 的使用手册。 此控件使用 Direct3D 绘制控件，并使用 DirectSound 对音频信号进行采样。

它有一个 AnalogSignalMeter 对象，它会触发一个报告当前左右扬声器电平的事件。

Answer 7

我不相信有一种简单的方法可以在 XP 下获得当前的峰值。 MIXERC​​ONTROL_CONTROLTYPE_PEAKMETER 存在，但我相信它在很大程度上不受支持（它在我当前的机器上）。 我猜您已经创建了自己的分析当前音频输出的方法，请查看此处的 DSP 部分。

您可以在运行时决定要使用哪种方法，XP 和 Vista/7 处理音频的方法非常不同。 我之前写的关于这个问题的一些可能有用的信息可以在这里。

在我看来，MSDN 文档和 Larry Osterman（他也是 SO 的成员）的博客可能是当前 Windows 音频基础设施的两个最有用的来源。