[FFmpeg-user] Can I speed up transcoding?

Carl Eugen Hoyos cehoyos at ag.or.at
Tue Jan 8 11:36:13 CET 2013

Henk D. Schoneveld <belcampo <at> zonnet.nl> writes:

> In your 1st posting, ffmpeg cli output, can be seen 
> that the file is encode with threads=1, 

(I had missed that, thank you. I am still against trying 
to auto-detect a value for threads and this case seems 
like a good reason to me, but apparently I am the only 
one thinking like that, see a related discussion on 
mplayer-users these days.)

> that suggests on EC2 only 1 cpu core is presented to 
> ffmpeg. So if more cores are available to you on EC2 
> you probably have to specifically have to ask for more 
> cores with the threads 2 after c:v. 
> Like ffmpeg -y -i some file.ext -c:v libx264 -threads 2  etc.

Note that -threads is both an input and an output option, 
it should therefore come before -i iirc.
(Or both before and after?)
And please test values significantly higher than 2.

Please do not top-post here, Carl Eugen

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