[Python-Dev] Test results of linuxaudiodev.c

[Michael Hudson]

Ka-Ping Yee <pingster@ilm.com> writes:

> On Thu, 29 Jun 2000, Ka-Ping Yee wrote:
> > Try setting the environment variable AUDIODEV to /dev/audio
> > before running the test script.  Does that work any better?
> 
> Even if that works, i realize that's not the way the interface
> was intended to be used.  To play an AU file, the routine should
> look something like this (not tested, as i don't have a working
> Linux box)...
[snip]

Yup, that works fine.  Don't understand the details - and as I have my
graduation ceremony tomorrow I'm going to go to bed and leave learning
them until some other occasion!

Cheers,
M.

PS: my Lib/test/test_linuxaudiodev.py is now this:

from test_support import verbose, findfile, TestFailed
import linuxaudiodev
import os,struct

def play_au_file(path):

    fp = open(path, "r")

    # Read the .au file header.
    header = fp.read(24)
    hdrsize, length, encoding, rate, channels = \
        struct.unpack(">xxxxiiiii", header)
    fp.read(hdrsize - 24)
    
    data = fp.read()
    fp.close()

    # Set the data format according to the code in the .au header.
    if encoding == 1:
        size, fmt = 8, linuxaudiodev.AFMT_MU_LAW
    elif encoding == 2:
        size, fmt = 8, linuxaudiodev.AFMT_S8
    elif encoding == 3:
        size, fmt = 16, linuxaudiodev.AFMT_S16_BE
    else:
        raise "audio format not supported"
        
    dsp = linuxaudiodev.open("w")
    dsp.setparameters(rate, size, channels, fmt)
    dsp.write(data)
    dsp.close()


def test():
    play_au_file(findfile('audiotest.au'))

test()

... which is an improvement on what's there now.