[Sndobj-devel] Using SndBuffer from Python

[Art B. <ac...@in...>]

Obviously I'm doing something wrong.  I'm a SndObj newbie and a Python-only chap to boot.  But I'm trying to get a simple buffered audio-in to audio-out loop to work... and apparently it's not quite as simple as I am.  So I'm reaching out for guidance.

I can substitute an Oscil for the SndRTIO and SndIn and I get a tone out, but somehow feeding the SndBuffer from the realtime input isn't the same.  The following runs ok for the prescribed ten seconds, but I hear nothing coming out.

#!/usr/bin/python
#####################################
#  Testing soundcard loopback
#  (this doesn't work)

import sndobj
import time

# set all to 16-bit (thanks Daniel Skinner)
vec = 2**16

snd = sndobj.SndObj()

# Set up the input thread to fill a buffer from soundcard input
inThread = sndobj.SndThread()
inp = sndobj.SndRTIO(1, sndobj.SND_INPUT, 512, 4, sndobj.SHORTSAM_LE, snd.GetInput(), vec, sndobj.DEF_SR, 'plughw:1,0')
sndin = sndobj.SndIn(inp, 1, vec)
inBuf = sndobj.SndBuffer(1,512)
inBuf.SetOutput(1, sndin)
inThread.AddObj(sndin)
inThread.AddObj(inBuf, sndobj.SNDIO_OUT)

# Set up the output thread to play from the buffer over another soundcard output
outThread = sndobj.SndRTThread()
sound = sndobj.SndIn(inBuf)
outp = sndobj.SndRTIO(1, sndobj.SND_OUTPUT, 512, 4, sndobj.SHORTSAM_LE, snd.GetInput(), vec, sndobj.DEF_SR, 'plughw:0,0')
outp.SetOutput(1, sound)
outThread.AddObj(inBuf, sndobj.SNDIO_IN)
outThread.AddObj(sound)
outThread.AddObj(outp, sndobj.SNDIO_OUT)

# Run both threads for ten seconds
inThread.ProcOn()
outThread.ProcOn()
time.sleep(10)
outThread.ProcOff()
inThread.ProcOff()

### EOF

Thanks in advance for any light that can shine on this!

- Art