I'm trying to find a way to read audio information from an external application via STDOUT. I'm currently using the AXE.Portaudio module but I cant seem to get it to work, all I get is a hissing noise :(
Below is a small example that I am currently trying to get working. It simply spawns a process (mov123), reads the audio data via STDOUT (44.1k 16bit) and then passes this information to the Portaudio functionality.
I would appreciate any feedback or suggestion as to how i can get the required functionality.
SuperStrict
Framework BRL.Basic
Import AXE.Portaudio
Import BRL.Map
Import PUB.FreeProcess
Type AudioProcessManager
Global map:TMap = New TMap
Global init:Byte = 0
Function CreateProcess:AudioProcess(command:String)
If init = 0 Then
Pa_Initialize()
init = 1
End If
Local ap:AudioProcess = New AudioProcess
map.Insert(String(ap.id), ap)
ap.command = command
Return ap
End Function
Function ReleaseProcess(ap:AudioProcess)
map.Remove(String(ap.id))
End Function
Function AudioCallback:Int( inputBuffer:Byte Ptr, outputBuffer:Byte Ptr, framesPerBuffer:Int, outTime:Double, userData:Byte Ptr)
Local ap:AudioProcess = AudioProcess(map.ValueForKey(String(userData[0])))
If Not ap Or Not ap.process Then
Return 0
End If
If ap.process.pipe.ReadAvail() >= framesPerBuffer Then
ap.process.pipe.Read(outputbuffer, framesPerBuffer)
End If
Return 0
End Function
End Type
Type AudioProcess
Global nextId:Int = 0
Field id:Int
Field command:String
Field process:TProcess
Field stream:Byte Ptr
Method New()
id = nextId
nextId:+1
End Method
Method play()
If process Then
stop()
End If
process = TProcess.Create(command, 0)
Pa_Initialize()
error(Pa_OpenStream( ..
Varptr stream, ..
PANODEVICE, ..
0, ..
2, ..
Null, ..
Pa_GetDefaultOutputDeviceID(), ..
2, ..
1, ..
Null, ..
44100, ..
256, ..
0, ..
0, ..
AudioProcessManager.AudioCallback, ..
Varptr id ..
), "open stream")
error(Pa_StartStream( stream ), "start stream")
End Method
Method stop()
If Not process Then
Return
End If
Pa_CloseStream(stream)
process.Terminate()
process.Close()
process = Null
End Method
Method isPlaying:Int()
If process And process.Status() <> 0 Then
Return True
End If
Return False
End Method
Method error(e:Int,s:String)
If e=0 Then Return
Pa_Terminate()
Print "error "+e+" in "+s
Print "message "+String.FromCString(Pa_GetErrorText(e))
End
End Method
End Type
Local cmd:String = "c:\mov123.exe ~qc:\test.mp3~q"
Local ap:AudioProcess = AudioProcessManager.CreateProcess(cmd)
Print ap.command
ap.play()
While ap.IsPlaying()
Delay(10000)
Wend
Print "End."
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