如何在 .wav 文件末尾添加几秒的静音？

Question

我有 1,440 个音频文件要输入神经网络。问题是它们的长度并不相同。我使用了发布的答案：

使用python向wav文件添加静音帧

但似乎不起作用。我想在文件末尾添加几秒钟的静音，然后将它们修剪为 5 秒长。有人可以帮我解决这个问题吗？

（我也尝试过使用 pysox，但这给了我

This install of SoX cannot process .wav files.

错误。）

我为此使用 Google Colab。代码是：

import wave, os, glob
from pydub import AudioSegment
from pydub.playback import play

path = 'drive/MyDrive/Ravdess/Sad' #This is the folder from my Google Drive which has the audio files
count = 0
for filename in glob.glob(os.path.join(path, '*.wav')):
    w = wave.open(filename, 'r')
    d = w.readframes(w.getnframes())
    frames = w.getnframes()
    rate = w.getframerate()
    duration = frames/float(rate)
    count+=1
    print(filename, "count =", count, "duration = ", duration)
    audio_in_file = filename
    audio_out_file = "out.wav"

    new_duration = duration
    #Only append silence until time = 5 seconds.

    one_sec = AudioSegment.silent(duration=2000) #duration in milliseconds
    song = AudioSegment.from_wav(audio_in_file)
    final_song = one_sec + song
    new_frames = w.getnframes()
    new_rate = w.getframerate()
    new_duration = new_frames/float(rate)
    final_song.export(audio_out_file, format="wav")
    print(final_song, "count =", count, "new duration = ", new_duration)

    w.close()

这给出了输出：

drive/MyDrive/Ravdess/Sad/03-01-04-01-02-01-01.wav count = 1 duration =  3.5035

<pydub.audio_segment.AudioSegment object at 0x7fd5b7ca06a0> count = 1 new duration =  3.5035

drive/MyDrive/Ravdess/Sad/03-01-04-01-02-02-01.wav count = 2 duration =  3.370041666666667

<pydub.audio_segment.AudioSegment object at 0x7fd5b7cbc860> count = 2 new duration =  3.370041666666667

... (and so on for all the files)

Answer 1

既然你已经在使用

pydub

，我会做这样的事情：

from pydub import AudioSegment
from pydub.playback import play

input_wav_file   = "/path/to/input.wav"
output_wav_file  = "/path/to/output.wav"
target_wav_time  = 5 * 1000 # 5 seconds (or 5000 milliseconds)

original_segment = AudioSegment.from_wav(input_wav_file)
silence_duration = target_wav_time - len(original_segment)
silenced_segment = AudioSegment.silent(duration=silence_duration)
combined_segment = original_segment + silenced_segment

combined_segment.export(output_wav_file, format="wav")

Answer 2

您可以一次性完成，而不是添加静音然后修剪文件（两倍的工作量）：

input_wav_file   = "/path/to/input.wav"
output_wav_file  = "/path/to/output.wav"
target_wav_time  = 5 * 1000 # (milliseconds)

original_segment = AudioSegment.from_wav(input_wav_file)
original_duration = len(original_segment)
print(f"Original duration: {original_duration}")

if original_duration < target_wav_time:
    silence_duration = target_wav_time - len(original_segment)
    print(f"Silence duration: {silence_duration}")
    silenced_segment = AudioSegment.silent(duration=silence_duration)
    combined_segment = original_segment + silenced_segment
    print(f"Combined duration: {len(combined_segment)}")
    combined_segment.export(output_wav_file, format="wav")

上面的代码，首先检查音频的持续时间是否短于5秒。如果音频较短，则会添加静音以将其延长到 5 秒，如果音频较长，则会跳过。