From 2889c5e16711770437f380f1bead5f72c6a0b17a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Martin=20Storsj=C3=B6?= Date: Fri, 6 Mar 2015 15:45:50 +0200 Subject: movenc: Heuristically set the duration of the last sample in a fragment if not set MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Even if this is a guess, it is way better than writing a zero duration of the last sample in a fragment (because if the duration is zero, the first sample of the next fragment will have the same timestamp as the last sample in the previous one). Since we normally don't require libavformat muxer users to set the duration field in AVPacket, we probably can't strictly require it here either, so don't log this as a strict warning, only as info. Signed-off-by: Martin Storsjö --- libavformat/movenc.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'libavformat/movenc.c') diff --git a/libavformat/movenc.c b/libavformat/movenc.c index ae7029d..d2d7561 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -3154,6 +3154,32 @@ static int mov_flush_fragment(AVFormatContext *s) if (!(mov->flags & FF_MOV_FLAG_FRAGMENT)) return 0; + for (i = 0; i < mov->nb_streams; i++) { + MOVTrack *track = &mov->tracks[i]; + if (track->entry <= 1) + continue; + // Sample durations are calculated as the diff of dts values, + // but for the last sample in a fragment, we don't know the dts + // of the first sample in the next fragment, so we have to rely + // on what was set as duration in the AVPacket. Not all callers + // set this though, so we might want to replace it with an + // estimate if it currently is zero. + if (get_cluster_duration(track, track->entry - 1) != 0) + continue; + // Use the duration (i.e. dts diff) of the second last sample for + // the last one. This is a wild guess (and fatal if it turns out + // to be too long), but probably the best we can do - having a zero + // duration is bad as well. + track->track_duration += get_cluster_duration(track, track->entry - 2); + if (!mov->missing_duration_warned) { + av_log(s, AV_LOG_WARNING, + "Estimating the duration of the last packet in a " + "fragment, consider setting the duration field in " + "AVPacket instead.\n"); + mov->missing_duration_warned = 1; + } + } + if (!mov->moov_written) { int64_t pos = avio_tell(s->pb); int ret; -- cgit v1.1