如何使用python向WAV文件添加噪音？

Question

I have a clean wav, and a wav containing a pre-generated noise, and I would like to add the noise to the clean wav file, to create a noisy wav.

I saw here this can be easily done with matlab.

How can this be done with python?

Answer 1

import numpy as np
from scikits.audiolab import wavread, wavwrite

data1, fs1, enc1 = wavread("file1.wav")
data2, fs2, enc2 = wavread("file2.wav")

assert fs1 == fs2
assert enc1 == enc2
result = 0.5 * data1 + 0.5 * data2

wavwrite(result, 'result.wav')

However, if you have different a sampling rate ( fs* ) or encoding ( enc* ) then you may have to try something more complex. (Sourced from here )

Additional

If you data* arrays are of different sizes, you could either just match the shortest array to a subset of the longer array:

min_size = min(len(data1), len(data2))

result = 0.5 * data1[:min_size] + 0.5 * data2[:min_size]

or you could wrap the shortest array so that it matches the length of the longest array:

short, long = (data1, data2) if len(data1) < len(data2) else (data2, data1)
n = len(long) / len(short)
new_array = np.tile(short, n)

result = 0.5 * long[:n] * 0.5 * new_array

These notes are outside the scope of your question. If you have further troubles you should probably mark this as solved and open up a new question.