Delay in Flac encoding

[Atlantis]

I have been spending several hours without success.

How to add delay in an ffmpeg flac encoding?

There is no video. So I want a "burned-in" delay. I have an ac3 file, using ffmpeg converting to flac I want a delay of -1000ms added to the flac output file in encoding phase. So later if I muxed it to a video, I don't need to add any delay to the muxer.

[hello_hello]

A -1000ms delay to all channels (or a 1000ms trim from the beginning).
Expressed as seconds so you'd specify either 1 or 1.000 or 1000ms.
-i input.ac3 -af atrim=start=1000ms -c:a flac output.flac

A +1000ms delay to all channels. Expressed as milliseconds.
-i input.ac3 -af adelay=delays=1000:all=1 -c:a flac output.flac

[Atlantis]

Thank you so much. Will try it later.

[TruthOverFacts]

A -1000ms delay to all channels (or a 1000ms trim from the beginning).
Expressed as seconds so you'd specify either 1 or 1.000 or 1000ms.
-i input.ac3 -af atrim=start=1000ms -c:a flac output.flac

A +1000ms delay to all channels. Expressed as milliseconds.
-i input.ac3 -af adelay=delays=1000:all=1 -c:a flac output.flac

Sent you a PM. Thanks!

[Balling]

ac3 has encoder delay too, 256 samples or more. Always. :)

[tebasuna51]

@Balling
Off topic answer, please read the question.

[SeeMoreDigital]

I often use an application called 'delaycut' (https://www.videohelp.com/software/delaycut). Which supports ac3, dts, mpa and (pcm in) wav files....