From a78c63eeef58116a22cb81177a5529a36df0133c Mon Sep 17 00:00:00 2001 From: Syed Andaleeb Roomy Date: Thu, 21 Jan 2016 07:08:09 +0100 Subject: [PATCH] movenc: Timecode in MP4 Although MP4 does not have a concrete specification to store timecode information, the following technical note from Apple describes a way to achieve this via timecode track, similar to how it is done for MOV files. https://developer.apple.com/library/mac/technotes/tn2174/_index.html - Enabled creation of timecode tracks for MP4 in the same way as MOV. - Used nmhd as media information header of timecode track of MP4 instead of gmhd used in MOV, thus avoiding tcmi also, as recommended above. - Bypassed adding source reference field for MP4, as suggested above. Issue: https://trac.ffmpeg.org/ticket/4704 Signed-off-by: Syed Andaleeb Roomy --- libavformat/movenc.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/libavformat/movenc.c b/libavformat/movenc.c index 1aff5c5..d615d16 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -1846,7 +1846,7 @@ static int mov_write_tmcd_tag(AVIOContext *pb, MOVTrack *track) if (track->st) t = av_dict_get(track->st->metadata, "reel_name", NULL, 0); - if (t && utf8len(t->value)) + if (t && utf8len(t->value) && track->mode != MODE_MP4) mov_write_source_reference_tag(pb, track, t->value); else avio_wb16(pb, 0); /* zero size */ @@ -2226,7 +2226,10 @@ static int mov_write_minf_tag(AVIOContext *pb, MOVMuxContext *mov, MOVTrack *tra } else if (track->tag == MKTAG('r','t','p',' ')) { mov_write_hmhd_tag(pb); } else if (track->tag == MKTAG('t','m','c','d')) { - mov_write_gmhd_tag(pb, track); + if (track->mode == MODE_MP4) + mov_write_nmhd_tag(pb); + else + mov_write_gmhd_tag(pb, track); } if (track->mode == MODE_MOV) /* FIXME: Why do it for MODE_MOV only ? */ mov_write_hdlr_tag(pb, NULL); @@ -5139,7 +5142,7 @@ static int mov_write_header(AVFormatContext *s) } } - if (mov->mode == MODE_MOV) { + if (mov->mode == MODE_MOV || mov->mode == MODE_MP4) { tmcd_track = mov->nb_streams; /* +1 tmcd track for each video stream with a timecode */ -- 2.6.1