无需在 Python 中写入磁盘即可加入 .wav 文件

Question

我有一个二进制格式的 .wav 文件列表（它们来自 websocket），我想加入一个二进制 .wav 文件，然后用它进行语音识别。我已经能够使用以下代码使其工作：

audio = [binary_wav1, binary_wav2,..., binary_wavN] # a list of .wav binary files coming from a socket
audio = [io.BytesIO(x) for x in audio]

# Join wav files
with wave.open('/tmp/input.wav', 'wb') as temp_input:
    params_set = False
    for audio_file in audio:
        with wave.open(audio_file, 'rb') as w:
            if not params_set:
                temp_input.setparams(w.getparams())
                params_set = True
            temp_input.writeframes(w.readframes(w.getnframes()))

# Do speech recognition
binary_audio = open('/tmp/input.wav', 'rb').read())
ASR(binary_audio)

问题是我不想将文件'/tmp/input.wav' 写入磁盘。有什么办法可以做到不写任何文件到磁盘？

谢谢。

Answer 1

拥有一个文件但从不将其放入磁盘的一般解决方案是流。为此，我们使用io 库，这是处理内存流的默认库。你甚至已经在你的代码前面使用了BytesIO。

audio = [binary_wav1, binary_wav2,..., binary_wavN] # a list of .wav binary files coming from a socket
audio = [io.BytesIO(x) for x in audio]

# Join wav files

params_set = False
temp_file = io.BytesIO()
with wave.open(temp_file, 'wb') as temp_input:
    for audio_file in audio:
        with wave.open(audio_file, 'rb') as w:
            if not params_set:
                temp_input.setparams(w.getparams())
                params_set = True
            temp_input.writeframes(w.readframes(w.getnframes()))

#move the cursor back to the beginning of the "file"
temp_file.seek(0)
# Do speech recognition
binary_audio = temp_file.read()
ASR(binary_audio)

注意我没有任何 .wav 文件可供试用。由wave 库来正确处理真实文件和缓冲流之间的差异。

Answer 2

使用 scipy 和 numpy，您可以将 wav 文件读取为 numpy 数组，然后进行您想要的修改。

from scipy.io import wavfile
import numpy as np

# load files
_, arr1 = wavfile.read('song.wav')
_, arr2 = wavfile.read('Aaron_Copland-Quiet_City.wav')

print(arr1.shape)
print(arr2.shape)

>>> (1323001,)
>>> (1323000,)

# make new array by concatenating two audio waves
new_arr = np.hstack((arr1, arr2))
print(new_arr.shape)

>>> (2646001,)

# save new audio wave
wavfile.write('new_audio.wav')