Hi On Mon, Sep 25, 2017 at 02:12:26PM -0700, John Stebbins wrote: > > > On 09/25/2017 01:12 PM, Carl Eugen Hoyos wrote: > > 2017-09-25 19:10 GMT+02:00 John Stebbins <jstebb...@jetheaddev.com>: > >> When keyframe intervals of dash segments are not perfectly aligned, > >> fragments in the stream can overlap in time. Append new "trun" index > >> entries to the end of the index instead of sorting by timestamp. > >> Sorting by timestamp causes packets to be read out of decode order and > >> results in decode errors. > >> --- > >> libavformat/mov.c | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/libavformat/mov.c b/libavformat/mov.c > >> index 2519707345..b2bc7c2c3d 100644 > >> --- a/libavformat/mov.c > >> +++ b/libavformat/mov.c > >> @@ -4339,8 +4339,8 @@ static int mov_read_trun(MOVContext *c, AVIOContext > >> *pb, MOVAtom atom) > >> MOV_FRAG_SAMPLE_FLAG_DEPENDS_YES)); > >> if (keyframe) > >> distance = 0; > >> - ctts_index = av_add_index_entry(st, offset, dts, sample_size, > >> distance, > >> - keyframe ? AVINDEX_KEYFRAME : 0); > >> + ctts_index = add_index_entry(st, offset, dts, sample_size, > >> distance, > >> + keyframe ? AVINDEX_KEYFRAME : 0); > > I can confirm that this fixes playback with FFplay but it shows > > many warnings (Non-monotonous DTS) with ffmpeg: Is this > > unavoidable? > > > > > > Fixing the non-monotonous DTS in ffmpeg would require more consideration. The > overlapping frames need to be dropped > somewhere after they are decoded and before they are presented. >
> I've given this some thought, but other ideas are certainly welcome. The > demuxer is probably the most appropriate place > for marking the frames as needing to be dropped since it has the "knowledge" > about why there are overlapping > timestamps. I.e. you only want to drop frames in this particular scenario > and not generally when timestamps go > backwards. I don't think there is currently any facility for marking frames > to be dropped after decoding, but it seems > like AVPacketSideData would be the appropriate mechanism for such marking. > FYI, such a facility for marking frames to > drop would also be useful for frame accurate playback of MP4 edit lists. This sounds like: /** * Flag is used to discard packets which are required to maintain valid * decoder state but are not required for output and should be dropped * after decoding. **/ #define AV_PKT_FLAG_DISCARD 0x0004 [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB What does censorship reveal? It reveals fear. -- Julian Assange
signature.asc
Description: Digital signature
_______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
