[FFmpeg-user] Can't get a/v synchronisation right with mpeg transport stream that has gaps in it

Carl Eugen Hoyos ceffmpeg at gmail.com
Wed Mar 29 10:47:42 EEST 2017

2017-03-28 13:17 GMT+02:00 Erik Slagter <erik at slagter.name>:


Without reading your report that contains a lot of information but
not what we absolutely need to help you:
Needs -async 1

> I was under the impression that ffmpeg would automatically base the
> synchronisation of the (single) audio stream on the (single) video
> stream. Is this a correct assumption or do I need to specify an explicit
> "-map" statement?

(After reading parts of your mail)
Unfortunately, it is not that simple:
Players can simply drop frames (or increase video playback speed)
for "missing" audio, this doesn't work with ffmpeg (the application),
silence has to be created and inserted.

Carl Eugen

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