[FFmpeg-user] How to change audio stream offset

[Carl Eugen Hoyos]

Francois Visagie <francois.visagie <at> gmail.com> writes:

> C:\Users\fvisagie\Videos\My DVDs\MainMovie\Neil Diamond Live at the
> Greek\VIDEO_TS\SPLITS>ffmpeg -i VTS_01_1.001.VOB -filter:a
> aformat=channel_layouts=stereo -p
> reset ultrafast bbb.mp4

Is this only reproducible using external libraries or 
also with -vcodec mpeg4 -acodec aac -strict -2 ?
(Unrelated: Note that the native aac encoder is said 
to produce better quality than libvo_aacenc.)

[...]

> Adding '-async 1' to the original batch encode command 
> line prevents this behaviour. However, it also makes 
> some encodes ~10% longer than their input

Could you elaborate, I don't understand what gets longer?

Carl Eugen