控制声道问题，急、在线等！

[tomhuang]

我用vb提供的Multimedia MCI 控件，想通过该控件实现对wav文件的播放，现在的问题是：wav文件是两个声道的，我如何控制其只通过左声道发音或者右声道发音，也就是说要关闭一个声道，请各位大侠指导，有示例更好，急、在线等！解决立即给分！！分不够再加

[tomhuang]

拜托还是发个给我吧。[e-mail]

[tomhuang]

为什么没人理我呢？都没办法吗？救命啊...

[bydisplay]

'VB源程序以下：
'1.modu1.bas
'2.form1.frm
'3.三个过程


'一、---------------modu1.bas
Private Declare Function auxGetVolume Lib "winmm.dll" (ByVal uDeviceID As Long, lpdwVolume As Long) As Long
Private Declare Function auxSetVolume Lib "winmm.dll" (ByVal uDeviceID As Long, ByVal dwVolume As Long) As Long
Private Declare Function waveOutGetVolume Lib "winmm.dll" ( _
ByVal uDeviceID As Long, _
lpdwVolume As Long _
) As Long
Private Declare Function waveOutSetVolume Lib "winmm.dll" (ByVal uDeviceID As Long, ByVal dwVolume As Long) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (hpvDest As Any, hpvSource As Any, ByVal cbCopy As Long)


Type VolumeSetting
LeftVol As Integer
RightVol As Integer
End Type

Public Const HIGHEST_VOLUME_SETTING = 12
Public Const WAVE_MAPPER = -1&

'下面是获取音量的函数:
Public Function lGetVolume(ByRef lLeftVol As Long, ByRef lRightVol As Long, lDeviceID As Long) As Long
Dim bReturnValue As Boolean
Dim Volume As VolumeSetting
Dim lAPIReturnVal As Long
Dim lBothVolumes As Long
lAPIReturnVal = waveOutGetVolume(lDeviceID, lBothVolumes)
lDataLen = Len(Volume)
CopyMemory Volume.LeftVol, lBothVolumes, lDataLen
lLeftVol = HIGHEST_VOLUME_SETTING * lUnsigned(Volume.LeftVol) / 65535
lRightVol = HIGHEST_VOLUME_SETTING * lUnsigned(Volume.RightVol) / 65535
lGetVolume = lAPIReturnVal
End Function

'下面是设置音量的函数:
Public Function lSetVolume(ByRef lLeftVol As Long, ByRef lRightVol As Long, lDeviceID As Long) As Long
Dim bReturnValue As Boolean
Dim Volume As VolumeSetting
Dim lAPIReturnVal As Long
Dim lBothVolumes As Long
Volume.LeftVol = nSigned(lLeftVol * 65535 / HIGHEST_VOLUME_SETTING)
Volume.RightVol = nSigned(lRightVol * 65535 / HIGHEST_VOLUME_SETTING)
lDataLen = Len(Volume)
CopyMemory lBothVolumes, Volume.LeftVol, lDataLen
lAPIReturnVal = waveOutSetVolume(lDeviceID, lBothVolumes)
lSetVolume = lAPIReturnVal
End Function

'** -> * 转换函数
Public Function nSigned(ByVal lUnsignedInt As Long) As Integer
Dim nReturnVal As Integer
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


'转换函数
Public Function lUnsigned(ByVal nSignedInt As Integer) As Long
Dim lReturnVal As Long
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


'二、---------------form1.frm
Private Sub cmd_Chancel_Click() '改变声道的按钮 caption='9左声'
'Sound PROC
If cmd_Chancel.Caption = "9立体" Then
cmd_Chancel.Caption = "9左声"
Call cmd_right_0_Click
Exit Sub
End If
If cmd_Chancel.Caption = "9左声" Then
cmd_Chancel.Caption = "9右声"
Call cmd_left_0_Click
Exit Sub
End If
If cmd_Chancel.Caption = "9右声" Then
cmd_Chancel.Caption = "9立体"
Call cmd_left_right_Click
Exit Sub
End If
End Sub

'三、---------------三个过程
Private Sub cmd_right_0_Click()
Dim L As Long, lleft As Long, lright As Long

lleft = lUnsigned(HIGHEST_VOLUME_SETTING)
lright = lUnsigned(0)

L = lSetVolume(lleft, lright, WAVE_MAPPER)

End Sub


Private Sub cmd_left_0_Click()
Dim L As Long, lleft As Long, lright As Long

lleft = lUnsigned(0)
lright = lUnsigned(HIGHEST_VOLUME_SETTING)

L = lSetVolume(lleft, lright, WAVE_MAPPER)

End Sub


Private Sub cmd_left_right_Click()
Dim L As Long, lleft As Long, lright As Long
lleft = lUnsigned(12)
lright = lUnsigned(12)

L = lSetVolume(lleft, lright, WAVE_MAPPER)

End Sub
'------------------完

[道素]

Public Sub SetBalance(mValue As Long)
Dim z As Long
Dim MxDetails As MIXERCONTROLDETAILS
Dim MxVolume(1) As MIXERCONTROLDETAILS_UNSIGNED
Dim volL As Long, volR As Long, tmpVol As Long
tmpVol = slVolume.Max - slVolume.Value
tmpVol = IIf(tmpVol = 0, 655, tmpVol)
volR = tmpVol * (IIf(mValue >= 0, 1, (100 + mValue) / 100))
volL = tmpVol * (IIf(mValue <= 0, 1, (100 - mValue) / 100))
MxDetails.item = Mix_Ctl.cMultipleItems
MxDetails.dwControlID = Mix_Ctl.dwControlID
MxDetails.cbStruct = Len(MxDetails)
MxDetails.cbDetails = Len(MxVolume(0))
MxDetails.cChannels = 2
hmem = GlobalAlloc(&H40, Len(MxVolume(0)))
MxDetails.paDetails = GlobalLock(hmem)
MxVolume(1).dwValue = volR
MxVolume(0).dwValue = volL
'two channels
CopyPtrFromStruct MxDetails.paDetails, MxVolume(1).dwValue, Len(MxVolume(0)) * MxDetails.cChannels
CopyPtrFromStruct MxDetails.paDetails, MxVolume(0).dwValue, Len(MxVolume(1)) * MxDetails.cChannels
z = mixerSetControlDetails(m_Mixer, MxDetails, MIXER_SETCONTROLDETAILSF_VALUE)
GlobalFree hmem
End Sub


Public Declare Function mixerClose Lib "winmm.dll" (ByVal hmx As Long) As Long
Public Declare Function mixerGetControlDetails Lib "winmm.dll" Alias "mixerGetControlDetailsA" (ByVal hmxobj As Long, pmxcd As MIXERCONTROLDETAILS, ByVal fdwDetails As Long) As Long
Public Declare Function mixerGetDevCaps Lib "winmm.dll" Alias "mixerGetDevCapsA" (ByVal uMxId As Long, pmxcaps As MIXERCAPS, ByVal cbmxcaps As Long) As Long
Public Declare Function mixerGetID Lib "winmm.dll" (ByVal hmxobj As Long, pumxID As Long, ByVal fdwId As Long) As Long
Public Declare Function mixerGetLineControls Lib "winmm.dll" Alias "mixerGetLineControlsA" (ByVal hmxobj As Long, pmxlc As MIXERLINECONTROLS, ByVal fdwControls As Long) As Long
Public Declare Function mixerGetLineInfo Lib "winmm.dll" Alias "mixerGetLineInfoA" (ByVal hmxobj As Long, pmxl As MIXERLINE, ByVal fdwInfo As Long) As Long
Public Declare Function mixerGetNumDevs Lib "winmm.dll" () As Long
Public Declare Function mixerMessage Lib "winmm.dll" (ByVal hmx As Long, ByVal uMsg As Long, ByVal dwParam1 As Long, ByVal dwParam2 As Long) As Long
Public Declare Function mixerOpen Lib "winmm.dll" (phmx As Long, ByVal uMxId As Long, ByVal dwCallback As Long, ByVal dwInstance As Long, ByVal fdwOpen As Long) As Long
Public Declare Function mixerSetControlDetails Lib "winmm.dll" (ByVal hmxobj As Long, pmxcd As MIXERCONTROLDETAILS, ByVal fdwDetails As Long) As Long
'Memory API
Public Declare Sub CopyStructFromPtr Lib "kernel32" Alias "RtlMoveMemory" (struct As Any, ByVal ptr As Long, ByVal cb As Long)
Public Declare Sub CopyPtrFromStruct Lib "kernel32" Alias "RtlMoveMemory" (ByVal ptr As Long, struct As Any, ByVal cb As Long)
Public Declare Function GlobalAlloc Lib "kernel32" (ByVal wFlags As Long, ByVal dwBytes As Long) As Long
Public Declare Function GlobalLock Lib "kernel32" (ByVal hmem As Long) As Long
Public Declare Function GlobalFree Lib "kernel32" (ByVal hmem As Long) As Long

[道素]

我的代码没贴全，如果需要我发个你
[e-mail]

[道素]

不用我发给你了
你下载这个好了，一样的：
http://www.planet-source-code.com/vb/scripts/ShowZip.asp?lngWId=1&lngCodeId=21757&strZipAccessCode=ODE%5F217575431