[Libav-user] strange H264 audio sync behavior

Carl Eugen Hoyos cehoyos at ag.or.at
Mon Jun 23 12:49:05 CEST 2014

Marco Sieber <l-spy at ...> writes:

> I switched now to 2.2 or the trunk Version, i have 
> to test it with that.

Please understand that only current FFmpeg git head 
is supported on this mailing list.

> >If you really need "-r 25" this indicates a problem
> >and it would explain why your application (if it
> >does sane things with timestamps) cannot work.
> If im right -r indicates a constant framerate? Why 
> should it not work

I believe there are three possibilities:
Your input file could be broken and contain random 
timestamps, in this case you need -r 25
FFmpeg might be unable to read the timestamps from 
your file correctly, in this case -r 25 is a 
Or the timestamps in your file are correct and 
FFmpeg can read them, in this case you should 
not use -r 25

Iirc, you have to read the time_base you set for 
a stream after setting it, FFmpeg might have 
changed it.

Carl Eugen

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