meh.py

def run_shell_cmd(cmd, shell=False, log_errors=True):
    log.debug('Running cmd %s', cmd)

    cmd = shlex.split(cmd) if not shell else cmd
    process = subprocess.Popen(
        cmd,
        shell=shell,
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        universal_newlines=True)
    stdout, stderr = process.communicate()

    return_code = process.poll()
    if return_code:
        if log_errors:
            log.error('Not 0 RC (%s, shell=%s) returned from %s', return_code, shell, cmd,
                      extra=dict(stdout=stdout, stderr=stderr))
        return False, return_code, cmd, stdout, stderr

    return True, return_code, cmd, stdout, stderr

def extract_audio_to_wav_ffmpeg(fpath, out_path, max_len_secs=None, sample_rate=16000, channels=1, codecs_opts=''):
    ''' extracts audio to given format (out_path.format) from audio/video '''

    FMAP = dict(wav='pcm_s16le', mp3='libmp3lame', flac='flac')
    _, ext = os.path.splitext(out_path)
    fmt = ext[1:]

    if fmt not in FMAP:
        raise ValueError('Not supported format: %s' % fmt)

    codecs_opts = ' ' + codecs_opts if codecs_opts else ''
    clip_len = ' -t %d' % max_len_secs if max_len_secs else ''
    ok, rc, cmd, stdout, stderr = run_shell_cmd(
        f'ffmpeg'
        f' -hide_banner'
        f' -nostats'
        f' -loglevel warning'
        f' -y'  # overwrite output file
        f' -vn'  # remove video
        f' -i \'{fpath}\''
        f' -acodec {FMAP[fmt]}'
        f' -ac {channels}'
        f' -ar {sample_rate}'
        f'{codecs_opts}'
        f'{clip_len}'
        f' \'{out_path}\'')

    if not ok:
        log.error('Fail to extract audio, cmd: %s, rc: %s, stdout: %s, stderr: %s',
                  cmd, rc, stdout, stderr, extra={'stack': True})
        raise AudioExtractionError(stderr)

    return ok