安装后不存在FFMpeg-Normalize

Question

我正在克隆this repo。我安装了ffmpeg-normalize，并且pip install ffmpeg-normalize返回

  

已经满足要求...

但是在执行preprocess.py步骤时，我得到了一个ffmpeg-normalize不存在的错误：

违规代码：

def preprocess(audio_filename, output_filename):
    ext_ind = audio_filename.rfind('.wav')
    audio_filename_formatted = audio_filename[:ext_ind] + '-formatted.wav'
    try:
        os.remove(audio_filename_formatted)
    except OSError:
        pass
    try:
        os.remove(output_filename)
    except OSError:
        pass
    error = os.system(
        'ffmpeg -i {} -acodec pcm_s16le -ac 1 -ar 16000 {}'.format(
            audio_filename, audio_filename_formatted))
    if error:
        print error
        raise StandardError('ffmpeg or audio file doesn\'t exist')
    error = os.system(
        'ffmpeg-normalize -f {}'.format(audio_filename_formatted))
    if error:
        raise StandardError('ffmpeg-normalize doesn\'t exist')

    data = wavfile.read(audio_filename_formatted)
    mfcc_inst = MFCC()
    features = mfcc_inst.sig2s2mfc_energy(data[1])

    np.save(output_filename, features)


if __name__ == '__main__':
    if len(sys.argv) < 3:
        sys.exit(
            "Have to pass audio_filename and output_filename as parameters.")
    print sys.argv[1],sys.argv[2]
    preprocess(sys.argv[1], sys.argv[2])

安装所需的步骤后还有其他步骤吗？在Mac上运行是否有问题？我在这里完全迷路了。预先谢谢你。