avio_wl64(pb, play_duration); /* end time stamp (in 100ns units) */
avio_wl64(pb, send_duration); /* duration (in 100ns units) */
avio_wl64(pb, PREROLL_TIME); /* start time stamp */
avio_wl64(pb, play_duration); /* end time stamp (in 100ns units) */
avio_wl64(pb, send_duration); /* duration (in 100ns units) */
avio_wl64(pb, PREROLL_TIME); /* start time stamp */