Extracts a single clip according to audioClipSpec.

        Arguments:
            audioClipSpec (AudioClipSpec): Clip specification
            showLogs (bool): Show ffmpeg output

def _extractClipData(self, audioClipSpec, showLogs=False):
        """Extracts a single clip according to audioClipSpec.

        Arguments:
            audioClipSpec (AudioClipSpec): Clip specification
            showLogs (bool): Show ffmpeg output
        """
        command = [self._ffmpegPath]

        if not showLogs:
            command += ['-nostats', '-loglevel', '0']

        command += [
            '-i', self._audioFilePath,
            '-ss', '%.3f' % audioClipSpec.start,
            '-t', '%.3f' % audioClipSpec.duration(),
            '-c', 'copy',
            '-map', '0',
            '-acodec', 'libmp3lame',
            '-ab', '128k',
            '-f', 'mp3'
        ]

        # Add clip TEXT as metadata and set a few more to default
        metadata = { self._textMetadataName: audioClipSpec.text }

        for k, v in metadata.items():
            command.append('-metadata')
            command.append("{}='{}'".format(k, v))

        command.append('pipe:1')

        return subprocess.check_output(command)