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I'm trying to convert Flac audio file to AAC file using command line.

So I wrote this

    ffmpeg -i input.flac temp.wav
    faac -q 120 -o output.m4a temp.wav

It's working fine. Now I want to do the same using fifo, so I'm writing this

   mkfifo temp.wav
   ffmpeg -i input.flac temp.wav  &   faac -q 120 -o output.m4a temp.wav

And it's freezing.

So could you tall me what I'm doing wrong.

Thanks a lot, and sorry for my English.

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migrated from Dec 28 '10 at 22:17

This question came from our site for professional and enthusiast programmers.

Why can't you simply pipe them: ffmpeg -i input.flac -f wav pipe: | faac -q 120 -o output.m4a - – adamax Dec 28 '10 at 14:48
Thanks, it's work.But could you tell me what I was doing wrong, and what is the syntax of making such pipe?. Thanks a lot. (I'm just a newbie in this) :) – Ashot Martirosyan Dec 28 '10 at 15:09
This is a question about running existing applications, not writing new ones, so I'm voting to move to superuser. – Ben Voigt Dec 28 '10 at 15:52
up vote 4 down vote accepted

FFmpeg doesn't support FIFOs, you'll have to use a pipe as suggested by @adamax , follow up on FFmpeg bug #1663 if you want/need FIFO support in FFmpeg.

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Use the -y switch. Some versions of ffmpeg hang while testing the existence of the named pipe. The y switch would be a work-around.

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