How to get the duration of a .WAV file that is not supported by the wave module in python?

Question

I am writing a program to annotate .wav files, so I need to play them and to know their duration. I can use the winsound module to play (using SND_ASYNC), but I can't use the wave module to read the file, because the compression of the files I use is not supported.

Should I use another module to get the duration of the .WAV files, or should I use one module for both playing and getting information about the files? What modules should I use?

Answer 1

Looking at the comments, this works (I made a few changes for my own readability). Thanks @Aya!

import os
path="c:\\windows\\system32\\loopymusic.wav"
f=open(path,"rb")

# read the ByteRate field from file (see the Microsoft RIFF WAVE file format)
# https://ccrma.stanford.edu/courses/422/projects/WaveFormat/
# ByteRate is located at the first 28th byte
f.seek(28)
a = f.read(4)

# convert string a into integer/longint value
# a is little endian, so proper conversion is required
byteRate = 0
for i in range(4):
    byteRate += a[i] * pow(256, i)

# get the file size in bytes
fileSize = os.path.getsize(path)  

# the duration of the data, in milliseconds, is given by
ms = ((fileSize - 44) * 1000)) / byteRate

print "File duration in miliseconds : " % ms
print "File duration in H,M,S,mS : " % ms / (3600 * 1000) % "," % ms / (60 * 1000) % "," % ms / 1000 % "," ms % 1000
print "Actual sound data (in bytes) : " % fileSize - 44
f.close()

Answer 2

Using SciPy:

 from scipy.io import wavfile
 Fs, x = wavfile.read("file.wav")
 print('Duration: ', len(x)/Fs)