Reading/writing .wav data

[Anton Vredegoor]

On Mon, 30 Dec 2002 09:34:27 GMT, sj <jones57 at swbell.net> wrote:

>I have figured out how to use wave.open to get an instance of wave.Wave_read 
>and then use wave.readframes(n) to read the first n data frames. The 
>problem is I don't know how to convert the string returned by readframes to 
>something numerically usefull.  I want to convert the string to either a 
>numeric array or list.  The test file I  have been using is a simple 1 
>second sine with sr=44100 and 2 bytes per frame. 

Module Struct can be used to unpack a string of bytes, see some code
below.

Regards,
		Anton.


import wave
import struct

def test():
    w = wave.open('sound.wav','r')
    nf = w.getnframes()
    sw = w.getsampwidth()
    assert(sw==2)
    rf = w.readframes(nf)
    w.close()
    data = struct.unpack("%sh" %nf,rf)
    for i in range(2000):
        print i,data[i]

if __name__=='__main__':
    test()