[FFmpeg-user] confusion with

Carl Eugen Hoyos cehoyos at ag.or.at
Thu Jan 17 00:00:56 CET 2013

Tracey Jaquith <tracey <at> archive.org> writes:

> MSNBCW_20121217_110000_Morning_Joe--bytes-1735000000-1810000000.mpg

I tested the following four command lines:

$ ffmpeg -i file -qscale 2 -acodec ac3 -ac 6 out6.avi
$ ffmpeg -i file -qscale 2 -acodec ac3 -ac 2 out2.avi
$ ffmpeg -i file -vcodec mpeg4 -qscale 2 -strict -2 -acodec aac -ac 6 out6.mov
$ ffmpeg -i file -vcodec mpeg4 -qscale 2 -strict -2 -acodec aac -ac 2 out2.mov

>From a quick look, all four output files play in-sync, 
so I suspect you shouldn't add any -async option.

(I agree that there is probably a bug but a sample that 
can not be converted in-sync because it needs -async 
and fails with -async would of course be much, much 

Carl Eugen

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