Using FFMPEG to extract video loses sync between sound and vision

[Jim web]

In article
<PHEAIHCMJKHMHMOFBPOGAEOLCMAA.c.e.macfarlane at macfh.co.uk>, C
E
Macfarlane <c.e.macfarlane at macfh.co.uk> wrote:

> ... and trying to extract a section of this ...

> http://www.bbc.co.uk/programmes/b06z8cxd

> ... with the following command ...

> FFMPEG -i CuirmCeltic-2016-1.mp4 -acodec copy -vcodec copy -ss 1211.5
> -to 1465 Chieftains.mp4

> ... leads to a result where the sound is out of sync with the vision. 
> Can anyone suggest a fix?

Two suggestions, but I don't know if they will fix it.

A newer version of ffmeg may help.

Convert the entire file to something like mkv first. Check that for lip
synch. Then snip that.

Jim

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