[FFmpeg-user] Using FFMPEG to encode multiple outputs in 'parallel' (doesn't work?)
forbyta at gmx.com
Thu Jun 29 00:47:52 EEST 2017
On Wed, 28 Jun 2017, shalin wrote:
> Nicolas George wrote
>> I think you need to take a little step back and learn what Unix pipes
>> mean. They are meant to connect the output of a process to the input of
>> the next one, but in your examples your commands neither consume their
>> input nor produce output.
> Piping only shows that I am trying to run all three ffmpeg transcode
> instances in parallel using single command line. If it makes any
> clearer, you can read them as three separate commands issued at the same
> time. With that, I hope we can focus on the concern raised in the
> original question.
As Nicolas already said, you need to take a closer look at "piping" vs
"background processing" in the UNIX shell.
What you are doing is PIPING:
<process 1> | <process 2> | <process 3>
This takes the output of process 1 and uses it as the input to process 2,
then the output of process 2 and uses it as the input to process 3.
It sounds like what you want is BACKGROUND PROCESSING:
<process 1> & <process 2> & process 3 &
This puts all 3 processes in the background and runs them concurrently.
You might want to check out some basics of the UNIX shell, such as this
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