- ContentTime position (boost::shared_ptr<const Film> film) const;
- void emit (boost::shared_ptr<const Film> film, AudioStreamPtr stream, boost::shared_ptr<const AudioBuffers>, ContentTime);
+ boost::optional<dcpomatic::ContentTime> position (boost::shared_ptr<const Film> film) const;
+ void emit (boost::shared_ptr<const Film> film, AudioStreamPtr stream, boost::shared_ptr<const AudioBuffers>, dcpomatic::ContentTime);