[FFmpeg-user] Where to cut audio by video frame?

[Karen Norton]

On Thu, Oct 10, 2019 at 12:41 PM Felix Muster via ffmpeg-user <
ffmpeg-user at ffmpeg.org> wrote:

> Hello
>
>
>
> I want to cut the audio from a scene of a movie (blu-ray 23.976 pfs).
>
> I want to create the cut from frame 2928 to 5177.
>
> Currently I don't know where I have to cut the audio to be accurate.
>
> Is the given command correct?
>
>
>
> ffmpeg.exe -i audio.flac -ss (2928/(24000/1001)) -t
> (5177/(24000/1001))-(2928/(24000/1001)) -codec flac audio_cut.flac
>
> ffmpeg.exe -i audio.flac -ss 122.122 -t 93.80204167 -codec flac
> audio_cut.flac
>
>
>
> And from the documentation I should use -ss as an output option to be
> accurate. But what is with -t? As input or output?
>
>
>
> Best
>
> Felix
>
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Would it not be easier to clip the video for the duration you want (frame
2928 to 5177) and then extract the audio from that clip? I have done this
before and it worked for my needs however I didn't check to see if there
was any loss of quality in the resulting audio by doing it this way. There
didn't seem to be but I didn't do an analysis of the clip to check it's
quality because, as mentioned, the audio I pulled from the video worked for
my needs.

Cheers.


Karen