[FFmpeg-user] redirect to 2 fifo files

Moritz Barsnick barsnick at gmx.net
Tue Jan 29 11:06:27 EET 2019

On Tue, Jan 29, 2019 at 07:18:21 +0100, Zoltan Kerenyi Nagy wrote:
>  $ ... -f wav pipe:3 -f wav pipe:4 3>fifo1 4>fifo2
> That's impossible since:
> pipe:1 stdout
> pipe:2: sterr
> pipe:0 stdin

That's not impossible. File descriptors 0, 1, 2 are predefined by the
operating system. A process can use further file descriptors, and in
this case I defined them as 3 and 4, and bash can handle their

> I got it working this way:
> https://pastebin.com/neYPWejt

I don't see two outputs being used.

Did you try my hint with "-f wav fifo1" and the addition of "-y"? It
works fine for me.

> The only thing have left is the video representation of the audio, which is
> a bonus to my sleep recorder experimental application


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