void image_subtitle (boost::weak_ptr<Piece>, ContentImageSubtitle);
void text_subtitle (boost::weak_ptr<Piece>, ContentTextSubtitle);
boost::shared_ptr<Resampler> resampler (boost::shared_ptr<const AudioContent> content, AudioStreamPtr stream, bool create);
void image_subtitle (boost::weak_ptr<Piece>, ContentImageSubtitle);
void text_subtitle (boost::weak_ptr<Piece>, ContentTextSubtitle);
boost::shared_ptr<Resampler> resampler (boost::shared_ptr<const AudioContent> content, AudioStreamPtr stream, bool create);