I was not happy with the answers for the last discussion on this so I thought I would try again. Here is some code that is designed to implement most of the stream2.c example in Visual Basic. It runs but only produces quiet clicks. Does anybody know what is wrong with this code? Byte order is not the problem.
‘ Try to implement the crucial parts of the stream2.c project in VB\
‘ Just call DoMain routine.
‘ Runs but only makes small clicking sound.
‘ What is wrong?
‘ R. Still 12-12-03
Private Type anint
ival As Integer
Private Type twobytes
byte1 As Byte
byte2 As Byte
Dim CallBackCount As Long
Dim t1 As Single, t2 As Single ‘ time
Dim v1 As Single, v2 As Single ‘ velocity
Function streamcallback(ByVal stream As Long, buff() As Byte, ByVal dlen As Long, ByVal param As Long) As Long
Dim count As Long
Dim byte1 As Byte, byte2 As Byte
Dim nsamps As Long
Dim ibuf As Long
Dim intval As Integer
Dim astr As String
On Error GoTo anerr ReDim buff(1 To dlen) nsamps = dlen / 4 ibuf = 1 astr = "" For count = 1 To nsamps ' // 16bit stereo (4 bytes per sample) (Should NOT be -1 ???) intval = Sin(t1) * 32767 ' // left channel IntToBytes intval, byte1, byte2 buff(ibuf) = byte1 buff(ibuf + 1) = byte2 If count < 6 Then astr = astr & " I>" & intval & "=" & byte1 & ":" & byte2 intval = Sin(t2) * 32767 ' // right channel IntToBytes intval, byte1, byte2 buff(ibuf + 2) = byte1 buff(ibuf + 3) = byte2 ibuf = ibuf + 4 t1 = t1 + 0.01 + v1 t2 = t2 + 0.0142 + v2 v1 = v1 + (Sin(t1) * 0.002) v2 = v2 + (Sin(t2) * 0.002) Next count
streamcallback = 1
CallBackCount = CallBackCount + 1
Debug.Print CallBackCount & " " & nsamps & " " & astr
MsgBox "CallBack ERR"
Function endcallback(ByVal stream As Long, buff() As Byte, ByVal dlen As Long, ByVal param As Long) As Long
endcallback = 1
Dim stream As Long
Dim result As Long
If FSOUND_GetVersion() < FMOD_VERSION Then MsgBox "Error : You are using the wrong DLL version! You should be using FMOD " & FMOD_VERSION Exit Sub End If result = FSOUND_SetOutput(FSOUND_OUTPUT_DSOUND) Select Case FSOUND_GetOutput() Case FSOUND_OUTPUT_NOSOUND Debug.Print "NoSound" Case FSOUND_OUTPUT_WINMM Debug.Print "Windows Multimedia Waveout" Case FSOUND_OUTPUT_DSOUND Debug.Print "Direct Sound" Case FSOUND_OUTPUT_ASIO Debug.Print "ASIO" Case Else MsgBox "Output type ERROR " & FSOUND_GetOutput() Exit Sub End Select result = FSOUND_Init(44100, 16, 0) If result <> 1 Then MsgBox "An error occured initializing fmod!" & vbCrLf & _ FSOUND_GetErrorString(FSOUND_GetError), vbOKOnly ' An error occured Exit Sub End If
stream = FSOUND_Stream_Create(AddressOf streamcallback, 6 * 2048, FSOUND_NORMAL + FSOUND_16BITS + FSOUND_STEREO, 44100, 12345)
result = FSOUND_Stream_SetEndCallback(stream, AddressOf endcallback, 0)
result = FSOUND_Stream_Play(FSOUND_FREE, stream)
If result = -1 Then MsgBox "An error occured initializing fmod!" & vbCrLf & _ FSOUND_GetErrorString(FSOUND_GetError), vbOKOnly End If MsgBox "Quit" result = FSOUND_Stream_Close(stream) result = FSOUND_Close()
Sub IntToBytes(a As Integer, b1 As Byte, b2 As Byte) ‘ Extract bytes from integer
Dim aval As anint
Dim bval As twobytes
aval.ival = a LSet bval = aval b1 = bval.byte1 b2 = bval.byte2
- Russell Still asked 14 years ago
Thanks, I changed the callback parameters and tried to use CopyMemory
to fill the buffer. However, the CopyMemory call kills the program.
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Function streamcallback(ByVal stream As Long, ByVal abuff As Long, ByVal dlen As Long, ByVal Param As Long) As Long
Dim buff() As Byte ReDim buff(1 To dlen)
...Fill up buff...
CopyMemory abuff, buff(1), dlen
- Anonymous answered 14 years ago
CopyMemory passes parameters ByRef by default, which means it will pass a pointer to the memoryadress where your variables are located.
This is fine for your buffer, since you want to copy that.
The value that the function passes is passed byval, and CONTAINS a pointer to the buffer you want to fill.
If you would pass this as a pointer, you would be passing a pointer to a pointer, which is not very useful, because it is not what the function expects.
To solve this in vb, you should pass the buffer reference ByVal, which is done as follows:
[code:2hhp3exb]CopyMemory ByVal abuff, buff(1), dlen[/code:2hhp3exb]
- Adion answered 14 years ago
you are writing your stream callbacks all wrong, here is the correct way:
Public Function endcallback(ByVal Stream As Long, ByVal buff As Long, ByVal length As Long, ByVal param As Long) As Long
'Put whatever you want it to do here. endcallback = 1
- Paranoid_Android answered 14 years ago
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