staircase->set_position (film, DCPTime::from_frames (2000, film->audio_frame_rate()));
staircase->set_trim_start (ContentTime::from_frames (12, 48000));
staircase->set_trim_end (ContentTime::from_frames (35, 48000));
staircase->set_position (film, DCPTime::from_frames (2000, film->audio_frame_rate()));
staircase->set_trim_start (ContentTime::from_frames (12, 48000));
staircase->set_trim_end (ContentTime::from_frames (35, 48000));