Attribute VB_Name = "Module1"
Option Explicit
Public Const CALLBACK_FUNCTION = &H30000
Public Const MMIO_READ = &H0
Public Const MMIO_FINDCHUNK = &H10
Public Const MMIO_FINDRIFF = &H20
Public Const MM_WOM_DONE = &H3BD
Type mmioinfo
   dwFlags As Long
   fccIOProc As Long
   pIOProc As Long
   wErrorRet As Long
   htask As Long
   cchBuffer As Long
   pchBuffer As String
   pchNext As String
   pchEndRead As String
   pchEndWrite As String
   lBufOffset As Long
   lDiskOffset As Long
   adwInfo(4) As Long
   dwReserved1 As Long
   dwReserved2 As Long
   hmmio As Long
End Type
Type WAVEHDR
   lpData As Long
   dwBufferLength As Long
   dwBytesRecorded As Long
   dwUser As Long
   dwFlags As Long
   dwLoops As Long
   lpNext As Long
   Reserved As Long
   End Type
   Type WAVEINCAPS
   wMid As Integer
   wPid As Integer
   vDriverVersion As Long
   szPname As String * 32
   dwFormats As Long
   wChannels As Integer
   End Type
   Type WAVEFORMAT
   wFormatTag As Integer
   nChannels As Integer
   nSamplesPerSec As Long
   nAvgBytesPerSec As Long
   nBlockAlign As Integer
   wBitsPerSample As Integer
   cbSize As Integer
End Type
Type MMCKINFO
    ckid As Long
    ckSize As Long
    fccType As Long
    dwDataOffset As Long
    dwFlags As Long
End Type
Declare Function waveOutOpen Lib "winmm.dll" (lphWaveIn As Long, _
    ByVal uDeviceID As Long, lpFormat As WAVEFORMAT, ByVal dwCallback As Long, _
    ByVal dwInstance As Long, ByVal dwFlags As Long) As Long
Declare Function waveOutPrepareHeader Lib "winmm.dll" (ByVal hWaveIn As Long, _
    lpWaveInHdr As WAVEHDR, ByVal uSize As Long) As Long
Declare Function waveOutReset Lib "winmm.dll" (ByVal hWaveIn As Long) As Long
Declare Function waveOutStart Lib "winmm.dll" (ByVal hWaveIn As Long) As Long
Declare Function waveOutStop Lib "winmm.dll" (ByVal hWaveIn As Long) As Long
Declare Function waveOutUnprepareHeader Lib "winmm.dll" (ByVal hWaveIn As Long, _
    lpWaveInHdr As WAVEHDR, ByVal uSize As Long) As Long
Declare Function waveOutClose Lib "winmm.dll" (ByVal hWaveIn As Long) As Long
Declare Function waveOutGetDevCaps Lib "winmm.dll" Alias "waveInGetDevCapsA" _
    (ByVal uDeviceID As Long, lpCaps As WAVEINCAPS, ByVal uSize As Long) As Long
Declare Function waveOutGetNumDevs Lib "winmm.dll" () As Long
Declare Function waveOutGetErrorText Lib "winmm.dll" Alias "waveInGetErrorTextA" _
    (ByVal err As Long, ByVal lpText As String, ByVal uSize As Long) As Long
Declare Function waveOutAddBuffer Lib "winmm.dll" (ByVal hWaveIn As Long, _
    lpWaveInHdr As WAVEHDR, ByVal uSize As Long) As Long
Declare Function waveOutWrite Lib "winmm.dll" (ByVal hWaveOut As Long, _
    lpWaveOutHdr As WAVEHDR, ByVal uSize As Long) As Long
Declare Function mmioClose Lib "winmm.dll" (ByVal hmmio As Long, ByVal uFlags As Long) As Long
Declare Function mmioDescend Lib "winmm.dll" (ByVal hmmio As Long, lpck As MMCKINFO, _
    lpckParent As MMCKINFO, ByVal uFlags As Long) As Long
Declare Function mmioDescendParent Lib "winmm.dll" Alias "mmioDescend" _
    (ByVal hmmio As Long, lpck As MMCKINFO, ByVal x As Long, ByVal uFlags As Long) As Long
Declare Function mmioOpen Lib "winmm.dll" Alias "mmioOpenA" (ByVal szFileName As String, _
    lpmmioinfo As mmioinfo, ByVal dwOpenFlags As Long) As Long
Declare Function mmioRead Lib "winmm.dll" (ByVal hmmio As Long, ByVal pch As Long, _
    ByVal cch As Long) As Long
Declare Function mmioReadFormat Lib "winmm.dll" Alias "mmioRead" (ByVal hmmio As Long, _
    ByRef pch As WAVEFORMAT, ByVal cch As Long) As Long
Declare Function mmioStringToFOURCC Lib "winmm.dll" Alias "mmioStringToFOURCCA" _
    (ByVal sz As String, ByVal uFlags As Long) As Long
Declare Function mmioAscend Lib "winmm.dll" (ByVal hmmio As Long, lpck As MMCKINFO, _
    ByVal uFlags As Long) As Long
Declare Function GlobalAlloc Lib "kernel32" (ByVal wFlags As Long, _
    ByVal dwBytes As Long) As Long
Declare Function GlobalLock Lib "kernel32" (ByVal hmem As Long) As Long
Declare Function GlobalFree Lib "kernel32" (ByVal hmem As Long) As Long
Declare Sub CopyStructFromPtr Lib "kernel32" Alias "RtlMoveMemory" (struct As Any, _
    ByVal ptr As Long, ByVal cb As Long)
Dim rc As Long
Dim msg As String * 200
Public format As WAVEFORMAT
Dim hmmioOut As Long
Dim mmckinfoParentIn As MMCKINFO
Dim mmckinfoSubchunkIn As MMCKINFO
Dim hWaveOut As Long
Dim bufferIn As Long
Dim hmem As Long
Dim outHdr As WAVEHDR
Public numSamples As Long
Public drawFrom As Long
Public drawTo As Long
Public fFileLoaded As Boolean
Public fPlaying As Boolean
Sub waveOutProc(ByVal hwi As Long, ByVal uMsg As Long, ByVal dwInstance As Long, _
    ByRef hdr As WAVEHDR, ByVal dwParam2 As Long)
   If (uMsg = MM_WOM_DONE) Then
      fPlaying = False
   End If
End Sub
Sub CloseWaveOut()
    rc = waveOutReset(hWaveOut)
    rc = waveOutUnprepareHeader(hWaveOut, outHdr, Len(outHdr))
    rc = waveOutClose(hWaveOut)
End Sub
Sub LoadFile(inFile As String)
   Dim hmmioIn As Long
   Dim mmioinf As mmioinfo
   fFileLoaded = False
   If (inFile = "") Then
       GlobalFree (hmem)
       Exit Sub
   End If
   hmmioIn = mmioOpen(inFile, mmioinf, MMIO_READ)
   If hmmioIn = 0 Then
       MsgBox "錯誤打開文件, rc = " & mmioinf.wErrorRet
       Exit Sub
   End If
   mmckinfoParentIn.fccType = mmioStringToFOURCC("WAVE", 0)
   rc = mmioDescendParent(hmmioIn, mmckinfoParentIn, 0, MMIO_FINDRIFF)
   If (rc <> 0) Then
       rc = mmioClose(hmmioOut, 0)
       MsgBox "不是一個聲音文件！"
       Exit Sub
   End If
   mmckinfoSubchunkIn.ckid = mmioStringToFOURCC("fmt", 0)
   rc = mmioDescend(hmmioIn, mmckinfoSubchunkIn, mmckinfoParentIn, MMIO_FINDCHUNK)
   If (rc <> 0) Then
       rc = mmioClose(hmmioOut, 0)
       MsgBox "不能讀取！"
       Exit Sub
   End If
   rc = mmioReadFormat(hmmioIn, format, Len(format))
   If (rc = -1) Then
      rc = mmioClose(hmmioOut, 0)
      MsgBox "格式錯誤！"
      Exit Sub
   End If
   rc = mmioAscend(hmmioIn, mmckinfoSubchunkIn, 0)
   mmckinfoSubchunkIn.ckid = mmioStringToFOURCC("data", 0)
   rc = mmioDescend(hmmioIn, mmckinfoSubchunkIn, mmckinfoParentIn, MMIO_FINDCHUNK)
   If (rc <> 0) Then
      rc = mmioClose(hmmioOut, 0)
      MsgBox "不能取得數據塊！"
      Exit Sub
   End If
   GlobalFree hmem
   hmem = GlobalAlloc(&H40, mmckinfoSubchunkIn.ckSize)
   bufferIn = GlobalLock(hmem)
   rc = mmioRead(hmmioIn, bufferIn, mmckinfoSubchunkIn.ckSize)
   numSamples = mmckinfoSubchunkIn.ckSize / format.nBlockAlign
   rc = mmioClose(hmmioOut, 0)
   fFileLoaded = True
End Sub
Sub Play(ByVal soundcard As Integer)
    rc = waveOutOpen(hWaveOut, soundcard, format, AddressOf waveOutProc, 0, CALLBACK_FUNCTION)
    If (rc <> 0) Then
      GlobalFree (hmem)
      waveOutGetErrorText rc, msg, Len(msg)
      MsgBox msg
      Exit Sub
    End If
    outHdr.lpData = bufferIn + (drawFrom * format.nBlockAlign)
    outHdr.dwBufferLength = (drawTo - drawFrom) * format.nBlockAlign
    outHdr.dwFlags = 0
    outHdr.dwLoops = 0
    rc = waveOutPrepareHeader(hWaveOut, outHdr, Len(outHdr))
    If (rc <> 0) Then
      waveOutGetErrorText rc, msg, Len(msg)
      MsgBox msg
    End If
    rc = waveOutWrite(hWaveOut, outHdr, Len(outHdr))
    If (rc <> 0) Then
      GlobalFree (hmem)
    Else
      fPlaying = True
      Form1.Timer1.Enabled = True
    End If
End Sub
Sub StopPlay()
   waveOutReset (hWaveOut)
End Sub
Sub GetStereo16Sample(ByVal sample As Long, ByRef leftVol As Double, ByRef rightVol As Double)
   Dim sample16 As Integer
   Dim ptr As Long
   ptr = sample * format.nBlockAlign + bufferIn
   CopyStructFromPtr sample16, ptr, 2
   leftVol = sample16 / 32768
   CopyStructFromPtr sample16, ptr + 2, 2
   rightVol = sample16 / 32768
End Sub
Sub GetStereo8Sample(ByVal sample As Long, ByRef leftVol As Double, ByRef rightVol As Double)
   Dim sample8 As Byte
   Dim ptr As Long
   ptr = sample * format.nBlockAlign + bufferIn
   CopyStructFromPtr sample8, ptr, 1
   leftVol = (sample8 - 128) / 128
   CopyStructFromPtr sample8, ptr + 1, 1
   rightVol = (sample8 - 128) / 128
End Sub
Sub GetMono16Sample(ByVal sample As Long, ByRef leftVol As Double)
   Dim sample16 As Integer
   Dim ptr As Long
   ptr = sample * format.nBlockAlign + bufferIn
   CopyStructFromPtr sample16, ptr, 2
   leftVol = sample16 / 32768
End Sub
Sub GetMono8Sample(ByVal sample As Long, ByRef leftVol As Double)
   Dim sample8 As Byte
   Dim ptr As Long
   ptr = sample * format.nBlockAlign + bufferIn
   CopyStructFromPtr sample8, ptr, 1
   leftVol = (sample8 - 128) / 128
End Sub