需要拆分立体声轨道，丢弃右声道，去除噪音

Question

我正在使用 Audacity 处理一些简短的音频剪辑 - 其中大约 300 个 (!!!)，所以我真的不想为每个剪辑手动重复我的步骤。

但是，我似乎无法找到一种方法来创建包含“拆分立体声轨道和丢弃右声道”步骤的链。我不知所措；有没有办法做到这一点？如果没有，是否还有其他程序可以让我以自动化方式执行此操作？

Answer 1

我建议使用sox这种东西。删除右声道：

sox in.wav out.wav remix 1

为了减少噪音，您需要从文件的静音部分获取噪音配置文件，即如下所示：

sox noisy.wav -n trim 0 1 noiseprof | play noisy.wav noisered

有关noiseprof 和noisered 的详细信息，请参见下文。

所以每个文件的序列看起来像这样，假设录音的第一秒只包含背景噪音：

sox in.wav -n remix 1 trim 0 1 noiseprof NOISE_PROFILE
sox in.wav out.wav remix 1 noisered NOISE_PROFILE

来自sox男人：

   noiseprof [profile-file]
          Calculate  a  profile of the audio for use in noise reduction.  See
          the description of the noisered effect for details.

   noisered [profile-file [amount]]
          Reduce noise in the audio signal by profiling and filtering.   This
          effect  is  moderately  effective at removing consistent background
          noise such as hiss or hum.  To use  it,  first  run  SoX  with  the
          noiseprof  effect  on a section of audio that ideally would contain
          silence but in fact contains noise - such  sections  are  typically
          found  at  the beginning or the end of a recording.  noiseprof will
          write out a noise profile to profile-file, or to stdout if no  pro-
          file-file or if `-' is given.  E.g.
             sox speech.wav -n trim 0 1.5 noiseprof speech.noise-profile
          To  actually  remove  the  noise, run SoX again, this time with the
          noisered effect; noisered will reduce noise according  to  a  noise
          profile  (which  was generated by noiseprof), from profile-file, or
          from stdin if no profile-file or if `-' is given.  E.g.
             sox speech.wav cleaned.wav noisered speech.noise-profile 0.3
          How much noise should be removed is specified  by  amount-a  number
          between  0 and 1 with a default of 0.5.  Higher numbers will remove
          more noise but present a greater likelihood of removing wanted com-
          ponents  of the audio signal.  Before replacing an original record-
          ing with a noise-reduced version, experiment with different  amount
          values  to  find  the optimal one for your audio; use headphones to
          check that you are happy with the results, paying particular atten-
          tion to quieter sections of the audio.

          On  most systems, the two stages - profiling and reduction - can be
          combined using a pipe, e.g.
             sox noisy.wav -n trim 0 1 noiseprof | play noisy.wav noisered