[RESOLVED] How to get a pointer to an element in a byte array?

When I got a pointer to a byte array, how to get a pointer to an element in this byte array? For example:

If the pointer to arrBytes(0) is 10000, then what is the pointer to the 44th element arrBytes(44)?

Description:
This question is a continuation of another thread:
http://www.vbforums.com/showthread.p...array-variable

When I get a pointer to a byte array, I need to do two actions on this array:
(1) Write a wav file header(it has 44 bytes) into this byte array. (This step has been completed)

(2) Write wav data, starting from the 44th byte of the byte array.

Because it is written through mmioRead API, I need to know the 44th byte pointer (memory address) of the byte array.

Edit:
Byte-array will be saved into the database

Quote:

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If the pointer to arrBytes(0) is 10000, then what is the pointer to the 44th element arrBytes(44)?

---

10044

Quote:

---

When I get a pointer to a byte array, I need to do two actions on this array:
(1) Write a wav file header(it has 44 bytes) into this byte array.
(This step has been completed)

(2) Write wav data, starting from the 44th byte of the byte array.
Because it is written through mmioRead API, I need to know the 44th byte pointer (memory address) of the byte array.

---

Don't. You can just use MMIO functions. I show you the code from TrickComposer to export a wave file to the file (you can change it to export to byte array without problem). It also store the tags of song you can remove/change:

Code:

---

Public Function ExportToWave( _
                ByVal curSong As Song, _
                ByRef fileName As String) As Boolean
    Dim Ret        As Long
    Dim hWave      As Long
    Dim chkRIFF    As MMCKINFO
    Dim chkData    As MMCKINFO
    Dim chkList    As MMCKINFO
    Dim chkSub      As MMCKINFO
    Dim dstFormat  As WAVEFORMATEX
    Dim buffer()    As Integer
    Dim Year        As String

    SetProgressState frmMain, TBPF_NORMAL
   
    curSong.SetPos 0

    dstFormat.wFormatTag = 1
    dstFormat.wBitsPerSample = 16
    dstFormat.nSamplesPerSec = curSong.SampleRate
    dstFormat.nChannels = 2
    dstFormat.nBlockAlign = (dstFormat.wBitsPerSample \ 8) * dstFormat.nChannels
    dstFormat.nAvgBytesPerSec = dstFormat.nBlockAlign * dstFormat.nSamplesPerSec
   
    If Len(Dir$(fileName)) Then Kill fileName
   
    ' // Create wave file
    hWave = mmioOpen(fileName, ByVal 0&, MMIO_WRITE Or MMIO_CREATE)
    If hWave = 0 Then
        MsgBox "Error creating wave file"
        GoTo ExitExport
    End If
   
    ' // Create RIFF-WAVE chunk
    chkRIFF.fccType = mmioStringToFOURCC("WAVE", 0)
    If mmioCreateChunk(hWave, chkRIFF, MMIO_CREATERIFF) Then
        mmioClose hWave
        MsgBox "Error creating RIFF-WAVE chunk"
        GoTo ExitExport
    End If
       
    ' // Create fmt chunk
    chkData.ckid = mmioStringToFOURCC("fmt", 0)
    If mmioCreateChunk(hWave, chkData, 0) Then
        mmioClose hWave
        MsgBox "Error creating fmt chunk"
        GoTo ExitExport
    End If
   
    ' // Write format
    If mmioWrite(hWave, dstFormat, Len(dstFormat)) = -1 Then
        mmioClose hWave
        MsgBox "Error writing format"
        GoTo ExitExport
    End If
   
    ' // Update fmt-chunk size
    mmioAscend hWave, chkData, 0
   
    ' // Create data chunk
    chkData.ckid = mmioStringToFOURCC("data", 0)
    If mmioCreateChunk(hWave, chkData, 0) Then
        mmioClose hWave
        MsgBox "Error creating data chunk"
        GoTo ExitExport
    End If

    ReDim buffer(12000 - 1)
   
    ' // Write pause
    If mmioWrite(hWave, buffer(0), (UBound(buffer) + 1) * Len(buffer(0))) = -1 Then
        mmioClose hWave
        MsgBox "Error writing data"
        GoTo ExitExport
    End If

    Do While curSong.GetPos <= curSong.SongDuration

        DoEvents

        curSong.Play buffer()

        ' // Write data
        If mmioWrite(hWave, buffer(0), (UBound(buffer) + 1) * Len(buffer(0))) = -1 Then
            mmioClose hWave
            MsgBox "Error writing data"
            GoTo ExitExport
        End If

        ZeroMemory buffer(0), (UBound(buffer) + 1) * Len(buffer(0))
       
        SetProgressValue frmMain, curSong.GetPos() / curSong.SongDuration()
       
        'frmMain.picProgress.Line (0, 0)-(curSong.GetPos(), 1), vbRed, BF

    Loop
     
    ' // Update data-chunk size
    mmioAscend hWave, chkData, 0
   
    ' // Create LIST chunk
    chkList.fccType = mmioStringToFOURCC("INFO", 0)
    If mmioCreateChunk(hWave, chkList, MMIO_CREATELIST) Then
        mmioClose hWave
        MsgBox "Error creating LIST-INFO chunk"
        GoTo ExitExport
    End If
   
    ' // Create IART chunk
    chkSub.ckid = mmioStringToFOURCC("IART", 0)
    If mmioCreateChunk(hWave, chkSub, 0) Then
        mmioClose hWave
        MsgBox "Error creating IART chunk"
        GoTo ExitExport
    End If
   
    ' // Write IART
    If mmioWrite(hWave, ByVal StrPtr(StrConv(ARTIST_NAME, vbFromUnicode)), Len(ARTIST_NAME)) = -1 Then
        mmioClose hWave
        MsgBox "Error writing IART"
        GoTo ExitExport
    End If
   
    ' // Update IART-chunk size
    mmioAscend hWave, chkSub, 0
   
    Year = CStr(DateTime.Year(Now))
   
    ' // Create ICRD chunk
    chkSub.ckid = mmioStringToFOURCC("ICRD", 0)
    If mmioCreateChunk(hWave, chkSub, 0) Then
        mmioClose hWave
        MsgBox "Error creating ICRD chunk"
        GoTo ExitExport
    End If
   
    ' // Write ICRD
    If mmioWrite(hWave, ByVal StrPtr(StrConv(Year, vbFromUnicode)), Len(Year)) = -1 Then
        mmioClose hWave
        MsgBox "Error writing ICRD"
        GoTo ExitExport
    End If
   
    ' // Update ICRD-chunk size
    mmioAscend hWave, chkSub, 0
   
    ' // Create IGNR chunk
    chkSub.ckid = mmioStringToFOURCC("IGNR", 0)
    If mmioCreateChunk(hWave, chkSub, 0) Then
        mmioClose hWave
        MsgBox "Error creating IGNR chunk"
        GoTo ExitExport
    End If
   
    ' // Write IGNR
    If mmioWrite(hWave, ByVal StrPtr(StrConv(GENRE_NAME, vbFromUnicode)), Len(GENRE_NAME)) = -1 Then
        mmioClose hWave
        MsgBox "Error writing IGNR"
        GoTo ExitExport
    End If
   
    ' // Update IGNR-chunk size
    mmioAscend hWave, chkSub, 0
   
    ' // Create INAM chunk
    chkSub.ckid = mmioStringToFOURCC("INAM", 0)
    If mmioCreateChunk(hWave, chkSub, 0) Then
        mmioClose hWave
        MsgBox "Error creating INAM chunk"
        GoTo ExitExport
    End If
   
    ' // Write INAM
    If mmioWrite(hWave, ByVal StrPtr(StrConv(curSong.Name, vbFromUnicode)), Len(curSong.Name)) = -1 Then
        mmioClose hWave
        MsgBox "Error writing INAM"
        GoTo ExitExport
    End If
   
    ' // Update INAM-chunk size
    mmioAscend hWave, chkSub, 0
   
    ' // Update LIST-chunk size
    mmioAscend hWave, chkList, 0
   
    ' // Update RIFF-chunk size
    mmioAscend hWave, chkRIFF, 0

    ExportToWave = True
   
ExitExport:
   
    mmioClose hWave
   
    SetProgressState frmMain, TBPF_NOPROGRESS

End Function

---

Sorry, I didn't make the question clear. I need to save a paragraph of a wav file as binary data into the database, and in the future this section of wave data could be read out and play. So, I wrote the following function:

Code:

---

Private Function ReadToByteArr(arrByte, Optional ByVal nStart_Sample As Long = 0, _
                                          Optional ByVal nEnd_Sample As Long = -1) As Boolean
    If nStart_Sample < 0 Or nEnd_Sample <= nStart_Sample Then Exit Function
    If VarType(arrByte) = vbString Then Exit Function
   
    Dim nBeginPos As Long:          Dim lpArrBytePtr As Long
    Dim nDataSize As Long

    ReDim arrByte(44 - 1) As Byte
           
    mmioSeek m_hInput, 0, SEEK_SET
           
    lpArrBytePtr = VarPtrVar(arrByte)
   
    '--- Write Wave Header ---
    If mmioRead(m_hInput, lpArrBytePtr, 44) = -1 Then
        MsgBox "Can't read wave header data":          Exit Function
    End If
   
    nDataSize = (nEnd_Sample - nStart_Sample) * 4
    nBeginPos = UBound(arrByte) + 1
    ReDim Preserve arrByte(nBeginPos + nDataSize - 1) As Byte
   
    '--- Seek Absolute
    mmioSeek m_hInput, (nStart_Sample * 4) + 44, SEEK_SET
 
    '--- Write wave data ---                           
    lpArrBytePtr = VarPtrVar(arrByte) + nBeginPos
    If mmioRead(m_hInput, lpArrBytePtr, nDataSize) = -1 Then
        MsgBox "Can't read wave data":          Exit Function
    End If
                                           
    ReadToByteArr = True
   
End Function

---

But writing data to the byte-array was not successfully, the problem is in the red line of the above source code.

dreammanor, you can use MMIO functions and parse all RIFF file to know format, data, tags etc because a RIFF file can contain data or format into other positions. You can use mmioDescend to search WAVE and fmt chunks and from given nBlockAlign you can calculate offset in bytes within data chunk.
To make the file in memory you also can use MMIO functions. mmioCreateChunk to create a WAVE and fmt chunks and copy data from first file (from database) to new in-memory-file.
You should make the same actions for data chunk. To update fields you just use mmioAscend function that store size of chunk.

Hi The trick, thanks for your advice. The function that I want to realize now is: How to use mmioRead to read a piece of wave data into a byte-array. I guess it should be done with array-pointer.

Edit:
I think of another way, that is, write the file-header to buffer1, then write the wave data to buffer2, and then merge buffer1 and buffer2 into buffer3 (or attach buffer2 to buffer1). But in this case, the speed will be much slower.

Quote:

---

Originally Posted by dreammanor

The function that I want to realize now is:
How to use mmioRead to read a piece of wave data into a byte-array.
I guess it should be done with array-pointer.

Edit:
I think of another way, that is, write the file-header to buffer1, then write the wave data to buffer2, and then merge buffer1 and buffer2 into buffer3 (or attach buffer2 to buffer1). But in this case, the speed will be much slower.

---

A few years ago, I wrote a little WavInfo-Class, which works (RC5-) Stream-Based -
and it parses out all the Info from a *.wav-file without using the mmio-API.

Beside the usual Wav-Format-Fields, it also gives reliable info about the Offset to the real PCM-Data
(which does not necessarily need to start at offset 44).

Here it is (I named it cWavInfo):

Code:

---

Option Explicit 'RC5-cStream-based Wav-info-reader (Author Olaf Schmidt, 2012)

'precalculated FourCCs
Private Const RIFF As Long = &H46464952, Wave As Long = &H45564157
Private Const data As Long = &H61746164, FMT_ As Long = &H20746D66

Private Type tRiffChunk
  ID As Long
  Size As Long
End Type
Private Type tWaveHeader
  RiffChunk As tRiffChunk
  RiffChunkFormat As Long
  RiffSubChunk As tRiffChunk
  WaveAudioFormat As Integer
  WaveNumChannels As Integer
  WaveSampleRate As Long
  WaveByteRate As Long
  WaveBlockAlign As Integer
  WaveBitsPerSample As Integer
  cbSize  As Integer
  wValidBitsPerSample  As Integer
  dwChannelMask  As Long
  SubFormat(0 To 7) As Integer
End Type

Private Header As tWaveHeader
Private mWaveMSec As Long, mWaveSamples As Long, mWaveDataOffs As Long, mWaveDataLen As Long

Public Sub ReadWaveInfoFromStream(Strm As cStream)
Dim Pos As Long, RiffChunk As tRiffChunk, EmptyHeader As tWaveHeader
  Header = EmptyHeader
  mWaveMSec = 0:    mWaveSamples = 0
  mWaveDataOffs = 0: mWaveDataLen = 0
  Strm.SetPosition 0
  Strm.ReadToPtr VarPtr(Header), Len(Header)
  If Header.RiffChunk.ID <> RIFF Then Err.Raise vbObjectError, , "The file is not in RIFF format."
  If Header.RiffChunkFormat <> Wave Then Err.Raise vbObjectError, , "The file is in RIFF format but is not a WAVE file."

  Do Until Header.RiffSubChunk.ID = FMT_
      Pos = Pos + Len(RiffChunk) + Header.RiffSubChunk.Size
      If Pos <= 0 Or Pos >= Strm.GetSize Then Err.Raise vbObjectError, , "The file is a WAVE file, but the header is corrupt."
      Strm.SetPosition Pos
      Strm.ReadToPtr VarPtr(Header), Len(Header)
  Loop

  Strm.SetPosition Pos + 20 + Header.RiffSubChunk.Size
  Strm.ReadToPtr VarPtr(RiffChunk), Len(RiffChunk)

  Do Until RiffChunk.ID = data
    Strm.SetPosition RiffChunk.Size, STRM_SeekFromCurPos
    If Strm.GetPosition = Strm.GetSize Then Err.Raise vbObjectError, , "The file is in RIFF format but is not a WAVE file."
    Strm.ReadToPtr VarPtr(RiffChunk), Len(RiffChunk)
  Loop
 
  If Header.RiffSubChunk.Size = 40 Then
    Header.WaveAudioFormat = Header.SubFormat(0)
  Else
    Header.wValidBitsPerSample = Header.WaveBitsPerSample
  End If
 
  mWaveDataLen = RiffChunk.Size
  mWaveDataOffs = Strm.GetPosition
   
  mWaveSamples = mWaveDataLen / Header.WaveNumChannels / (Header.WaveBitsPerSample / 8)
  mWaveMSec = (mWaveSamples / Header.WaveSampleRate) * 1000
End Sub
 
Public Property Get AudioFormat() As Long
  AudioFormat = Header.WaveAudioFormat
End Property
Public Property Get AudioFormatString() As String
  AudioFormatString = Choose(AudioFormat + 1, "Unknown", "PCM", "ADPCM", "IEEE_FLOAT")
End Property

Public Property Get Channels() As Integer
  Channels = Header.WaveNumChannels
End Property

Public Property Get SampleRate() As Long
  SampleRate = Header.WaveSampleRate
End Property

Public Property Get ByteRate() As Long
  ByteRate = Header.WaveByteRate
End Property
 
Public Property Get BitsPerSample() As Integer
  BitsPerSample = Header.WaveBitsPerSample
End Property

Public Property Get BlockAlign() As Integer
  BlockAlign = Header.WaveBlockAlign
End Property

Public Property Get ValidBitsPerSample() As Integer
  ValidBitsPerSample = Header.wValidBitsPerSample
End Property

Public Property Get Samples() As Long
  Samples = mWaveSamples
End Property

Public Property Get DataOffs() As Long
  DataOffs = mWaveDataOffs
End Property
Public Property Get DataLen() As Long
  DataLen = mWaveDataLen
End Property
Public Property Get DataLenSec() As Double
  DataLenSec = mWaveMSec / 1000
End Property
Public Property Get DataLen_msec() As Long
  DataLen_msec = mWaveMSec
End Property

---

And if your intent is, to describe (and later play) shorter "Selection-Snippets" from a larger Wav-File,
you could use a cSelection-Class like the following (which has 4 Read/Write-Props and 2 "calculated ones"):

Code:

---

Option Explicit

Public StreamTotalLengthSec As Double, StartPerc As Double, EndPerc As Double, Text As String
 
Public Property Get StreamOffsetSeconds() As Double
  StreamOffsetSeconds = StartPerc * StreamTotalLengthSec
End Property

Public Property Get LengthSeconds() As Double
  LengthSeconds = EndPerc * StreamTotalLengthSec - StreamOffsetSeconds
End Property

---

Well, once you're "armed" with the two little Classes above, the remaining Form-Demo-Code becomes as simple as that:
(define a Wav-File of your choice in Form_Load, and then click the Form).

Code:

---

Option Explicit
 
Private Declare Function PlaySound& Lib "winmm" (data As Any, Optional ByVal hMod&, Optional ByVal Flags& = 5)

Private Stream As cStream, WavInfo As New cWavInfo

Private Sub Form_Load()
  Set Stream = New_c.FSO.OpenFileStream("c:\temp\SampleLoop.wav")
  WavInfo.ReadWaveInfoFromStream Stream
End Sub
 
Private Sub Form_Click()
  'init a Selection-Object with the Duration from cWavInfo and a Percent-Range
  Dim Sel As New cSelection
      Sel.StreamTotalLengthSec = WavInfo.DataLenSec
      Sel.StartPerc = 0.15
      Sel.EndPerc = 0.35
     
  'now play the selection-snippet
  PlaySelection Sel, WavInfo
End Sub

Public Sub PlaySelection(Sel As cSelection, WavInfo As cWavInfo)
  If Sel Is Nothing Or Stream Is Nothing Then Exit Sub
  With WavInfo
    Dim B() As Byte: B = "" 'init B to an empty Array
    Stream.SetPosition .DataOffs + Int(Sel.StreamOffsetSeconds * .SampleRate) * .BlockAlign
    Stream.ReadToByteArr B, Int(Sel.LengthSeconds * .SampleRate) * .BlockAlign
    PlayWavBuf .SampleRate, .Channels, .BitsPerSample, B
  End With
End Sub

Public Sub PlayWavBuf(ByVal Freq As Long, ByVal Channels As Long, ByVal Bits As Long, WavBuf() As Byte)
  PlaySound ByVal 0& 'cancel any (potentially) still asynchronously playing sounds
  Static B() As Byte
  Dim WavBufLen As Long, Strm As cStream
      WavBufLen = UBound(WavBuf) + 1
 
  Set Strm = New_c.Stream 'let's create an InMemory-Stream
      Strm.WriteFromByteArr StrConv("RIFF    WAVEfmt                    data    ", vbFromUnicode)
      Strm.WriteFromByteArr WavBuf
      Strm.SetPosition 4:  Strm.WriteFromPtr VarPtr(WavBufLen + 36), 4 'FileSize (without the 8 Riff-Hdr-Bytes)
      Strm.SetPosition 16: Strm.WriteFromPtr VarPtr(16&), 4            'Format-Data-Length
      Strm.WriteFromPtr VarPtr(1 + 65536 * Channels), 4                'PCM=1 + Channels
      Strm.WriteFromPtr VarPtr(Freq), 4                                'Samples per second
      Strm.WriteFromPtr VarPtr(Freq * Channels * Bits \ 8), 4          'Bytes per second
      Strm.WriteFromPtr VarPtr(Channels * Bits \ 8 + 65536 * Bits), 4  'Bytes per Sample + Bits
      Strm.SetPosition 40: Strm.WriteFromPtr VarPtr(WavBufLen), 4      'Wav-Data-length
      Strm.SetPosition 0 'prepare for a re-read of the whole stream (now including the header)
  If Strm.ReadToByteArr(B) Then PlaySound B(0) 'read and finally play the (now wav-hdr-prefixed) buffer
End Sub
 
Private Sub Form_Terminate()
  PlaySound ByVal 0& 'cancel any (potentially) still asynchronously playing sounds
  New_c.CleanupRichClientDll
End Sub

---

The above PlaySelection-Function (which works in conjunction with the WavInfo-Class and the RC5-cStream-Class),
answers a lot of your recent questions I assume.

HTH

Olaf

Code:

---

Option Explicit

Private Const FOURCC_MEM      As Long = &H204D454D
Private Const MMIO_CREATERIFF As Long = &H20
Private Const MMIO_DIRTY      As Long = &H10000000
Private Const MMIO_CREATE    As Long = &H1000
Private Const MMIO_WRITE      As Long = &H1
Private Const MMIO_READWRITE  As Long = &H2
Private Const WAVE_FORMAT_PCM As Long = 1
Private Const SEEK_SET        As Long = 0
Private Const MMIO_FINDCHUNK  As Long = &H10
Private Const MMIO_FINDRIFF  As Long = &H20

Private Type MMCKINFO
    ckid            As Long
    ckSize          As Long
    fccType        As Long
    dwDataOffset    As Long
    dwFlags        As Long
End Type

Private Type MMIOINFO
    dwFlags        As Long
    fccIOProc      As Long
    pIOProc        As Long
    wErrorRet      As Long
    htask          As Long
    cchBuffer      As Long
    pchBuffer      As Long
    pchNext        As Long
    pchEndRead      As Long
    pchEndWrite    As Long
    lBufOffset      As Long
    lDiskOffset    As Long
    adwInfo(4)      As Long
    dwReserved1    As Long
    dwReserved2    As Long
    hmmio          As Long
End Type

Private Type WAVEFORMATEX
    wFormatTag      As Integer
    nChannels      As Integer
    nSamplesPerSec  As Long
    nAvgBytesPerSec As Long
    nBlockAlign    As Integer
    wBitsPerSample  As Integer
    cbSize          As Integer
End Type

Private Declare Function mmioClose Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        Optional ByVal uFlags As Long) As Long
Private Declare Function mmioOpen Lib "winmm.dll" _
                        Alias "mmioOpenW" ( _
                        ByVal szFileName As Long, _
                        ByRef lpmmioinfo As Any, _
                        ByVal dwOpenFlags As Long) As Long
Private Declare Function mmioStringToFOURCC Lib "winmm.dll" _
                        Alias "mmioStringToFOURCCA" ( _
                        ByVal sz As String, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioAscend Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpck As MMCKINFO, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioCreateChunk Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpck As MMCKINFO, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioWrite Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef pch As Any, _
                        ByVal cch As Long) As Long
Private Declare Function mmioDescend Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpck As MMCKINFO, _
                        ByRef lpckParent As Any, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioSeek Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByVal lOffset As Long, _
                        ByVal iOrigin As Long) As Long
Private Declare Function memcpy Lib "kernel32" _
                        Alias "RtlMoveMemory" ( _
                        ByRef Destination As Any, _
                        ByRef Source As Any, _
                        ByVal Length As Long) As Long
Private Declare Function mmioRead Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef pch As Any, _
                        ByVal cch As Long) As Long
Private Declare Function mmioGetInfo Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpmmioinfo As Any, _
                        ByVal wFlags As Long) As Long

Sub main()
    Dim bData()    As Byte
    Dim bOutPart()  As Byte
   
    ' // Open file to array
    Open "E:\Distance_to_Mars.wav" For Binary Access Read As #1
    ReDim bData(LOF(1) - 1)
    Get 1, , bData
    Close 1
   
    ' // Extract part of file to other file in-memory
    ' // Select from 1777777 sample to 1777777 + 55556 sample
    ExtractPartOfWaveFile bData(), 1777777, 55556, bOutPart()
   
    ' // Save part of file to file
    Open "E:\Distance_to_Mars_part.wav" For Binary Access Write As #1
    Put 1, , bOutPart
    Close 1
   
End Sub

' // Extract part of a WAVE-file-in-memory to other WAVE-file-in-memory
' // !!! NO BOUNDS CHECKING (arrays etc.) !!!
Private Function ExtractPartOfWaveFile( _
                ByRef bData() As Byte, _
                ByVal lStartSample As Long, _
                ByVal lLength As Long, _
                ByRef bOut() As Byte) As Boolean
    Dim tIoInfo        As MMIOINFO
    Dim tckRIFF        As MMCKINFO
    Dim tckWAVE        As MMCKINFO
    Dim tckFMT          As MMCKINFO
    Dim tckDATA        As MMCKINFO
    Dim bInData()      As Byte
    Dim bFMT()          As Byte
    Dim hOutFile        As Long
   
    If Not ExtractData(bData(), lStartSample, lLength, bInData(), bFMT()) Then
        Exit Function
    End If
   
    With tIoInfo
        .fccIOProc = FOURCC_MEM
        .cchBuffer = 2048
        .adwInfo(0) = 2048& * 2048
    End With
   
    hOutFile = mmioOpen(0, tIoInfo, MMIO_READWRITE Or MMIO_CREATE)
    If hOutFile = 0 Then
        MsgBox "Error opening wave file"
        Exit Function
    End If

    tckRIFF.fccType = mmioStringToFOURCC("WAVE", 0)
   
    If mmioCreateChunk(hOutFile, tckRIFF, MMIO_CREATERIFF) Then
        MsgBox "Error creating RIFF-WAVE chunk"
        GoTo CleanUp
    End If
   
    tckFMT.ckid = mmioStringToFOURCC("fmt", 0)
   
    If mmioCreateChunk(hOutFile, tckFMT, 0) Then
        MsgBox "Error creating fmt chunk"
        GoTo CleanUp
    End If
   
    If mmioWrite(hOutFile, bFMT(0), UBound(bFMT) + 1) = -1 Then
        MsgBox "Error writing format"
        GoTo CleanUp
    End If
   
    mmioAscend hOutFile, tckFMT, 0
   
    tckDATA.ckid = mmioStringToFOURCC("data", 0)
   
    If mmioCreateChunk(hOutFile, tckDATA, 0) Then
        MsgBox "Error creating data chunk"
        GoTo CleanUp
    End If
   
    If mmioWrite(hOutFile, bInData(0), UBound(bInData) + 1) = -1 Then
        MsgBox "Error writing data"
        GoTo CleanUp
    End If
   
    mmioAscend hOutFile, tckDATA, 0
    mmioAscend hOutFile, tckRIFF, 0
   
    If mmioGetInfo(hOutFile, tIoInfo, 0) Then
        MsgBox "Unable to get stream info"
        GoTo CleanUp
    End If
   
    ReDim bOut(tIoInfo.pchNext - tIoInfo.pchBuffer - 1)
   
    memcpy bOut(0), ByVal tIoInfo.pchBuffer, UBound(bOut) + 1
   
    ExtractPartOfWaveFile = True
   
CleanUp:
   
    mmioClose hOutFile, 0
   
End Function

' // Extract format and part of data from in-memory-file
Private Function ExtractData( _
                ByRef bData() As Byte, _
                ByVal lStartSample As Long, _
                ByVal lLength As Long, _
                ByRef bOut() As Byte, _
                ByRef bFMT() As Byte) As Boolean
    Dim tIoInfo        As MMIOINFO
    Dim tckRIFF        As MMCKINFO
    Dim tckWAVE        As MMCKINFO
    Dim tckFMT          As MMCKINFO
    Dim tckDATA        As MMCKINFO
    Dim tFMT            As WAVEFORMATEX
    Dim hInFile        As Long
    Dim lByteOffset    As Long
    Dim lBytesCount    As Long
   
    With tIoInfo
        .fccIOProc = FOURCC_MEM
        .cchBuffer = UBound(bData) + 1
        .pchBuffer = VarPtr(bData(0))
    End With
   
    hInFile = mmioOpen(0, tIoInfo, MMIO_READWRITE)
    If hInFile = 0 Then
        MsgBox "Error opening wave file"
        Exit Function
    End If

    tckWAVE.fccType = mmioStringToFOURCC("WAVE", 0)

    If mmioDescend(hInFile, tckWAVE, ByVal 0&, MMIO_FINDRIFF) Then
        MsgBox "Is not valid file"
        GoTo CleanUp
    End If
   
    tckFMT.ckid = mmioStringToFOURCC("fmt", 0)
   
    If mmioDescend(hInFile, tckFMT, tckWAVE, MMIO_FINDCHUNK) Then
        MsgBox "Format chunk not found"
        GoTo CleanUp
    End If
   
    If tckFMT.ckSize < 0 Then
        MsgBox "Invalid format"
        GoTo CleanUp
    End If
   
    ReDim bFMT(tckFMT.ckSize - 1)
   
    If mmioRead(hInFile, bFMT(0), tckFMT.ckSize) = -1 Then
        MsgBox "Can't read format"
        GoTo CleanUp
    End If
   
    mmioAscend hInFile, tckFMT, 0
   
    tckDATA.ckid = mmioStringToFOURCC("data", 0)

    If mmioDescend(hInFile, tckDATA, tckWAVE, MMIO_FINDCHUNK) Then
        MsgBox "Wave data is not found"
        GoTo CleanUp
    End If
   
    If tckDATA.ckSize <= 0 Then
        MsgBox "Invalid data size"
        GoTo CleanUp
    End If
   
    If tckFMT.ckSize > Len(tFMT) Then
        tckFMT.ckSize = Len(tFMT)
    End If
   
    memcpy tFMT, bFMT(0), tckFMT.ckSize
   
    lByteOffset = lStartSample * tFMT.nBlockAlign
    lBytesCount = lLength * tFMT.nBlockAlign
   
    If mmioSeek(hInFile, tckDATA.dwDataOffset + lByteOffset, SEEK_SET) = -1 Then
        MsgBox "Unable to locate data"
        GoTo CleanUp
    End If
   
    ReDim bOut(lBytesCount - 1)
   
    If mmioRead(hInFile, bOut(0), lBytesCount) = -1 Then
        MsgBox "Can't read data"
        GoTo CleanUp
    End If
   
    ExtractData = True
   
CleanUp:
   
    mmioClose hInFile, 0
   
End Function

---

Quote:

---

Originally Posted by The trick

Code:

---

Option Explicit

Private Const FOURCC_MEM      As Long = &H204D454D
Private Const MMIO_CREATERIFF As Long = &H20
Private Const MMIO_DIRTY      As Long = &H10000000
Private Const MMIO_CREATE    As Long = &H1000
Private Const MMIO_WRITE      As Long = &H1
Private Const MMIO_READWRITE  As Long = &H2
Private Const WAVE_FORMAT_PCM As Long = 1
Private Const SEEK_SET        As Long = 0
Private Const MMIO_FINDCHUNK  As Long = &H10
Private Const MMIO_FINDRIFF  As Long = &H20

Private Type MMCKINFO
    ckid            As Long
    ckSize          As Long
    fccType        As Long
    dwDataOffset    As Long
    dwFlags        As Long
End Type

Private Type MMIOINFO
    dwFlags        As Long
    fccIOProc      As Long
    pIOProc        As Long
    wErrorRet      As Long
    htask          As Long
    cchBuffer      As Long
    pchBuffer      As Long
    pchNext        As Long
    pchEndRead      As Long
    pchEndWrite    As Long
    lBufOffset      As Long
    lDiskOffset    As Long
    adwInfo(4)      As Long
    dwReserved1    As Long
    dwReserved2    As Long
    hmmio          As Long
End Type

Private Type WAVEFORMATEX
    wFormatTag      As Integer
    nChannels      As Integer
    nSamplesPerSec  As Long
    nAvgBytesPerSec As Long
    nBlockAlign    As Integer
    wBitsPerSample  As Integer
    cbSize          As Integer
End Type

Private Declare Function mmioClose Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        Optional ByVal uFlags As Long) As Long
Private Declare Function mmioOpen Lib "winmm.dll" _
                        Alias "mmioOpenW" ( _
                        ByVal szFileName As Long, _
                        ByRef lpmmioinfo As Any, _
                        ByVal dwOpenFlags As Long) As Long
Private Declare Function mmioStringToFOURCC Lib "winmm.dll" _
                        Alias "mmioStringToFOURCCA" ( _
                        ByVal sz As String, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioAscend Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpck As MMCKINFO, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioCreateChunk Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpck As MMCKINFO, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioWrite Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef pch As Any, _
                        ByVal cch As Long) As Long
Private Declare Function mmioDescend Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpck As MMCKINFO, _
                        ByRef lpckParent As Any, _
                        ByVal uFlags As Long) As Long
Private Declare Function mmioSeek Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByVal lOffset As Long, _
                        ByVal iOrigin As Long) As Long
Private Declare Function memcpy Lib "kernel32" _
                        Alias "RtlMoveMemory" ( _
                        ByRef Destination As Any, _
                        ByRef Source As Any, _
                        ByVal Length As Long) As Long
Private Declare Function mmioRead Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef pch As Any, _
                        ByVal cch As Long) As Long
Private Declare Function mmioGetInfo Lib "winmm.dll" ( _
                        ByVal hmmio As Long, _
                        ByRef lpmmioinfo As Any, _
                        ByVal wFlags As Long) As Long

Sub main()
    Dim bData()    As Byte
    Dim bOutPart()  As Byte
   
    ' // Open file to array
    Open "E:\Distance_to_Mars.wav" For Binary Access Read As #1
    ReDim bData(LOF(1) - 1)
    Get 1, , bData
    Close 1
   
    ' // Extract part of file to other file in-memory
    ' // Select from 1777777 sample to 1777777 + 55556 sample
    ExtractPartOfWaveFile bData(), 1777777, 55556, bOutPart()
   
    ' // Save part of file to file
    Open "E:\Distance_to_Mars_part.wav" For Binary Access Write As #1
    Put 1, , bOutPart
    Close 1
   
End Sub

' // Extract part of a WAVE-file-in-memory to other WAVE-file-in-memory
' // !!! NO BOUNDS CHECKING (arrays etc.) !!!
Private Function ExtractPartOfWaveFile( _
                ByRef bData() As Byte, _
                ByVal lStartSample As Long, _
                ByVal lLength As Long, _
                ByRef bOut() As Byte) As Boolean
    Dim tIoInfo        As MMIOINFO
    Dim tckRIFF        As MMCKINFO
    Dim tckWAVE        As MMCKINFO
    Dim tckFMT          As MMCKINFO
    Dim tckDATA        As MMCKINFO
    Dim bInData()      As Byte
    Dim bFMT()          As Byte
    Dim hOutFile        As Long
   
    If Not ExtractData(bData(), lStartSample, lLength, bInData(), bFMT()) Then
        Exit Function
    End If
   
    With tIoInfo
        .fccIOProc = FOURCC_MEM
        .cchBuffer = 2048
        .adwInfo(0) = 2048& * 2048
    End With
   
    hOutFile = mmioOpen(0, tIoInfo, MMIO_READWRITE Or MMIO_CREATE)
    If hOutFile = 0 Then
        MsgBox "Error opening wave file"
        Exit Function
    End If

    tckRIFF.fccType = mmioStringToFOURCC("WAVE", 0)
   
    If mmioCreateChunk(hOutFile, tckRIFF, MMIO_CREATERIFF) Then
        MsgBox "Error creating RIFF-WAVE chunk"
        GoTo CleanUp
    End If
   
    tckFMT.ckid = mmioStringToFOURCC("fmt", 0)
   
    If mmioCreateChunk(hOutFile, tckFMT, 0) Then
        MsgBox "Error creating fmt chunk"
        GoTo CleanUp
    End If
   
    If mmioWrite(hOutFile, bFMT(0), UBound(bFMT) + 1) = -1 Then
        MsgBox "Error writing format"
        GoTo CleanUp
    End If
   
    mmioAscend hOutFile, tckFMT, 0
   
    tckDATA.ckid = mmioStringToFOURCC("data", 0)
   
    If mmioCreateChunk(hOutFile, tckDATA, 0) Then
        MsgBox "Error creating data chunk"
        GoTo CleanUp
    End If
   
    If mmioWrite(hOutFile, bInData(0), UBound(bInData) + 1) = -1 Then
        MsgBox "Error writing data"
        GoTo CleanUp
    End If
   
    mmioAscend hOutFile, tckDATA, 0
    mmioAscend hOutFile, tckRIFF, 0
   
    If mmioGetInfo(hOutFile, tIoInfo, 0) Then
        MsgBox "Unable to get stream info"
        GoTo CleanUp
    End If
   
    ReDim bOut(tIoInfo.pchNext - tIoInfo.pchBuffer - 1)
   
    memcpy bOut(0), ByVal tIoInfo.pchBuffer, UBound(bOut) + 1
   
    ExtractPartOfWaveFile = True
   
CleanUp:
   
    mmioClose hOutFile, 0
   
End Function

' // Extract format and part of data from in-memory-file
Private Function ExtractData( _
                ByRef bData() As Byte, _
                ByVal lStartSample As Long, _
                ByVal lLength As Long, _
                ByRef bOut() As Byte, _
                ByRef bFMT() As Byte) As Boolean
    Dim tIoInfo        As MMIOINFO
    Dim tckRIFF        As MMCKINFO
    Dim tckWAVE        As MMCKINFO
    Dim tckFMT          As MMCKINFO
    Dim tckDATA        As MMCKINFO
    Dim tFMT            As WAVEFORMATEX
    Dim hInFile        As Long
    Dim lByteOffset    As Long
    Dim lBytesCount    As Long
   
    With tIoInfo
        .fccIOProc = FOURCC_MEM
        .cchBuffer = UBound(bData) + 1
        .pchBuffer = VarPtr(bData(0))
    End With
   
    hInFile = mmioOpen(0, tIoInfo, MMIO_READWRITE)
    If hInFile = 0 Then
        MsgBox "Error opening wave file"
        Exit Function
    End If

    tckWAVE.fccType = mmioStringToFOURCC("WAVE", 0)

    If mmioDescend(hInFile, tckWAVE, ByVal 0&, MMIO_FINDRIFF) Then
        MsgBox "Is not valid file"
        GoTo CleanUp
    End If
   
    tckFMT.ckid = mmioStringToFOURCC("fmt", 0)
   
    If mmioDescend(hInFile, tckFMT, tckWAVE, MMIO_FINDCHUNK) Then
        MsgBox "Format chunk not found"
        GoTo CleanUp
    End If
   
    If tckFMT.ckSize < 0 Then
        MsgBox "Invalid format"
        GoTo CleanUp
    End If
   
    ReDim bFMT(tckFMT.ckSize - 1)
   
    If mmioRead(hInFile, bFMT(0), tckFMT.ckSize) = -1 Then
        MsgBox "Can't read format"
        GoTo CleanUp
    End If
   
    mmioAscend hInFile, tckFMT, 0
   
    tckDATA.ckid = mmioStringToFOURCC("data", 0)

    If mmioDescend(hInFile, tckDATA, tckWAVE, MMIO_FINDCHUNK) Then
        MsgBox "Wave data is not found"
        GoTo CleanUp
    End If
   
    If tckDATA.ckSize <= 0 Then
        MsgBox "Invalid data size"
        GoTo CleanUp
    End If
   
    If tckFMT.ckSize > Len(tFMT) Then
        tckFMT.ckSize = Len(tFMT)
    End If
   
    memcpy tFMT, bFMT(0), tckFMT.ckSize
   
    lByteOffset = lStartSample * tFMT.nBlockAlign
    lBytesCount = lLength * tFMT.nBlockAlign
   
    If mmioSeek(hInFile, tckDATA.dwDataOffset + lByteOffset, SEEK_SET) = -1 Then
        MsgBox "Unable to locate data"
        GoTo CleanUp
    End If
   
    ReDim bOut(lBytesCount - 1)
   
    If mmioRead(hInFile, bOut(0), lBytesCount) = -1 Then
        MsgBox "Can't read data"
        GoTo CleanUp
    End If
   
    ExtractData = True
   
CleanUp:
   
    mmioClose hInFile, 0
   
End Function

---

---

Hi The trick, after reading your source code, I realized that the way I wrote the wave file-header was wrong. Your source code completely solved my problem. Extremely grateful.

Quote:

---

Originally Posted by Schmidt

A few years ago, I wrote a little WavInfo-Class, which works (RC5-) Stream-Based -
and it parses out all the Info from a *.wav-file without using the mmio-API.

Beside the usual Wav-Format-Fields, it also gives reliable info about the Offset to the real PCM-Data
(which does not necessarily need to start at offset 44).

Here it is (I named it cWavInfo):

Code:

---

Option Explicit 'RC5-cStream-based Wav-info-reader (Author Olaf Schmidt, 2012)

'precalculated FourCCs
Private Const RIFF As Long = &H46464952, Wave As Long = &H45564157
Private Const data As Long = &H61746164, FMT_ As Long = &H20746D66

Private Type tRiffChunk
  ID As Long
  Size As Long
End Type
Private Type tWaveHeader
  RiffChunk As tRiffChunk
  RiffChunkFormat As Long
  RiffSubChunk As tRiffChunk
  WaveAudioFormat As Integer
  WaveNumChannels As Integer
  WaveSampleRate As Long
  WaveByteRate As Long
  WaveBlockAlign As Integer
  WaveBitsPerSample As Integer
  cbSize  As Integer
  wValidBitsPerSample  As Integer
  dwChannelMask  As Long
  SubFormat(0 To 7) As Integer
End Type

Private Header As tWaveHeader
Private mWaveMSec As Long, mWaveSamples As Long, mWaveDataOffs As Long, mWaveDataLen As Long

Public Sub ReadWaveInfoFromStream(Strm As cStream)
Dim Pos As Long, RiffChunk As tRiffChunk, EmptyHeader As tWaveHeader
  Header = EmptyHeader
  mWaveMSec = 0:    mWaveSamples = 0
  mWaveDataOffs = 0: mWaveDataLen = 0
  Strm.SetPosition 0
  Strm.ReadToPtr VarPtr(Header), Len(Header)
  If Header.RiffChunk.ID <> RIFF Then Err.Raise vbObjectError, , "The file is not in RIFF format."
  If Header.RiffChunkFormat <> Wave Then Err.Raise vbObjectError, , "The file is in RIFF format but is not a WAVE file."

  Do Until Header.RiffSubChunk.ID = FMT_
      Pos = Pos + Len(RiffChunk) + Header.RiffSubChunk.Size
      If Pos <= 0 Or Pos >= Strm.GetSize Then Err.Raise vbObjectError, , "The file is a WAVE file, but the header is corrupt."
      Strm.SetPosition Pos
      Strm.ReadToPtr VarPtr(Header), Len(Header)
  Loop

  Strm.SetPosition Pos + 20 + Header.RiffSubChunk.Size
  Strm.ReadToPtr VarPtr(RiffChunk), Len(RiffChunk)

  Do Until RiffChunk.ID = data
    Strm.SetPosition RiffChunk.Size, STRM_SeekFromCurPos
    If Strm.GetPosition = Strm.GetSize Then Err.Raise vbObjectError, , "The file is in RIFF format but is not a WAVE file."
    Strm.ReadToPtr VarPtr(RiffChunk), Len(RiffChunk)
  Loop
 
  If Header.RiffSubChunk.Size = 40 Then
    Header.WaveAudioFormat = Header.SubFormat(0)
  Else
    Header.wValidBitsPerSample = Header.WaveBitsPerSample
  End If
 
  mWaveDataLen = RiffChunk.Size
  mWaveDataOffs = Strm.GetPosition
   
  mWaveSamples = mWaveDataLen / Header.WaveNumChannels / (Header.WaveBitsPerSample / 8)
  mWaveMSec = (mWaveSamples / Header.WaveSampleRate) * 1000
End Sub
 
Public Property Get AudioFormat() As Long
  AudioFormat = Header.WaveAudioFormat
End Property
Public Property Get AudioFormatString() As String
  AudioFormatString = Choose(AudioFormat + 1, "Unknown", "PCM", "ADPCM", "IEEE_FLOAT")
End Property

Public Property Get Channels() As Integer
  Channels = Header.WaveNumChannels
End Property

Public Property Get SampleRate() As Long
  SampleRate = Header.WaveSampleRate
End Property

Public Property Get ByteRate() As Long
  ByteRate = Header.WaveByteRate
End Property
 
Public Property Get BitsPerSample() As Integer
  BitsPerSample = Header.WaveBitsPerSample
End Property

Public Property Get BlockAlign() As Integer
  BlockAlign = Header.WaveBlockAlign
End Property

Public Property Get ValidBitsPerSample() As Integer
  ValidBitsPerSample = Header.wValidBitsPerSample
End Property

Public Property Get Samples() As Long
  Samples = mWaveSamples
End Property

Public Property Get DataOffs() As Long
  DataOffs = mWaveDataOffs
End Property
Public Property Get DataLen() As Long
  DataLen = mWaveDataLen
End Property
Public Property Get DataLenSec() As Double
  DataLenSec = mWaveMSec / 1000
End Property
Public Property Get DataLen_msec() As Long
  DataLen_msec = mWaveMSec
End Property

---

And if your intent is, to describe (and later play) shorter "Selection-Snippets" from a larger Wav-File,
you could use a cSelection-Class like the following (which has 4 Read/Write-Props and 2 "calculated ones"):

Code:

---

Option Explicit

Public StreamTotalLengthSec As Double, StartPerc As Double, EndPerc As Double, Text As String
 
Public Property Get StreamOffsetSeconds() As Double
  StreamOffsetSeconds = StartPerc * StreamTotalLengthSec
End Property

Public Property Get LengthSeconds() As Double
  LengthSeconds = EndPerc * StreamTotalLengthSec - StreamOffsetSeconds
End Property

---

Well, once you're "armed" with the two little Classes above, the remaining Form-Demo-Code becomes as simple as that:
(define a Wav-File of your choice in Form_Load, and then click the Form).

Code:

---

Option Explicit
 
Private Declare Function PlaySound& Lib "winmm" (data As Any, Optional ByVal hMod&, Optional ByVal Flags& = 5)

Private Stream As cStream, WavInfo As New cWavInfo

Private Sub Form_Load()
  Set Stream = New_c.FSO.OpenFileStream("c:\temp\SampleLoop.wav")
  WavInfo.ReadWaveInfoFromStream Stream
End Sub
 
Private Sub Form_Click()
  'init a Selection-Object with the Duration from cWavInfo and a Percent-Range
  Dim Sel As New cSelection
      Sel.StreamTotalLengthSec = WavInfo.DataLenSec
      Sel.StartPerc = 0.15
      Sel.EndPerc = 0.35
     
  'now play the selection-snippet
  PlaySelection Sel, WavInfo
End Sub

Public Sub PlaySelection(Sel As cSelection, WavInfo As cWavInfo)
  If Sel Is Nothing Or Stream Is Nothing Then Exit Sub
  With WavInfo
    Dim B() As Byte: B = "" 'init B to an empty Array
    Stream.SetPosition .DataOffs + Int(Sel.StreamOffsetSeconds * .SampleRate) * .BlockAlign
    Stream.ReadToByteArr B, Int(Sel.LengthSeconds * .SampleRate) * .BlockAlign
    PlayWavBuf .SampleRate, .Channels, .BitsPerSample, B
  End With
End Sub

Public Sub PlayWavBuf(ByVal Freq As Long, ByVal Channels As Long, ByVal Bits As Long, WavBuf() As Byte)
  PlaySound ByVal 0& 'cancel any (potentially) still asynchronously playing sounds
  Static B() As Byte
  Dim WavBufLen As Long, Strm As cStream
      WavBufLen = UBound(WavBuf) + 1
 
  Set Strm = New_c.Stream 'let's create an InMemory-Stream
      Strm.WriteFromByteArr StrConv("RIFF    WAVEfmt                    data    ", vbFromUnicode)
      Strm.WriteFromByteArr WavBuf
      Strm.SetPosition 4:  Strm.WriteFromPtr VarPtr(WavBufLen + 36), 4 'FileSize (without the 8 Riff-Hdr-Bytes)
      Strm.SetPosition 16: Strm.WriteFromPtr VarPtr(16&), 4            'Format-Data-Length
      Strm.WriteFromPtr VarPtr(1 + 65536 * Channels), 4                'PCM=1 + Channels
      Strm.WriteFromPtr VarPtr(Freq), 4                                'Samples per second
      Strm.WriteFromPtr VarPtr(Freq * Channels * Bits \ 8), 4          'Bytes per second
      Strm.WriteFromPtr VarPtr(Channels * Bits \ 8 + 65536 * Bits), 4  'Bytes per Sample + Bits
      Strm.SetPosition 40: Strm.WriteFromPtr VarPtr(WavBufLen), 4      'Wav-Data-length
      Strm.SetPosition 0 'prepare for a re-read of the whole stream (now including the header)
  If Strm.ReadToByteArr(B) Then PlaySound B(0) 'read and finally play the (now wav-hdr-prefixed) buffer
End Sub
 
Private Sub Form_Terminate()
  PlaySound ByVal 0& 'cancel any (potentially) still asynchronously playing sounds
  New_c.CleanupRichClientDll
End Sub

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The above PlaySelection-Function (which works in conjunction with the WavInfo-Class and the RC5-cStream-Class),
answers a lot of your recent questions I assume.

HTH

Olaf

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Hi Olaf, I tested the source code you provided and it worked very well. Both of your method and The Trick's method can completely solve my problem, and these two different methods will all be added to my project. Extremely grateful.