- 1. One of them starts at time 0.
- 2. The first video PTS value ends up on a frame boundary.
-
- Then we remove big initial gaps in PTS and we allow our
- insertion of black frames to work.
-
- We will do:
- audio_pts_to_use = audio_pts_from_ffmpeg + pts_offset;
- video_pts_to_use = video_pts_from_ffmpeg + pts_offset;
- */
-
- /* First, make one of them start at 0 */
-
- vector<shared_ptr<FFmpegAudioStream> > streams = c->ffmpeg_audio_streams ();
-
- _pts_offset = ContentTime::min ();
-
- if (c->first_video ()) {
- _pts_offset = - c->first_video().get ();
- }
-
- BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, streams) {
- if (i->first_audio) {
- _pts_offset = max (_pts_offset, - i->first_audio.get ());
- }
- }
-
- /* If _pts_offset is positive we would be pushing things from a -ve PTS to be played.
- I don't think we ever want to do that, as it seems things at -ve PTS are not meant
- to be seen (use for alignment bars etc.); see mantis #418.
- */
- if (_pts_offset > ContentTime ()) {
- _pts_offset = ContentTime ();
- }
-
- /* Now adjust so that the video pts starts on a frame */
- if (c->first_video ()) {
- ContentTime first_video = c->first_video().get() + _pts_offset;
- ContentTime const old_first_video = first_video;
- _pts_offset += first_video.round_up (c->video_frame_rate ()) - old_first_video;
- }