void decode_and_process_subtitle_packet (AVPacket* packet);
void process_bitmap_subtitle (AVSubtitleRect const * rect, dcpomatic::ContentTime from);
void process_ass_subtitle (std::string ass, dcpomatic::ContentTime from);
void maybe_add_subtitle ();
void decode_and_process_subtitle_packet (AVPacket* packet);
void process_bitmap_subtitle (AVSubtitleRect const * rect, dcpomatic::ContentTime from);
void process_ass_subtitle (std::string ass, dcpomatic::ContentTime from);
void maybe_add_subtitle ();