[FFmpeg-user] Can I speed up transcoding?

Carl Eugen Hoyos cehoyos at ag.or.at
Tue Jan 8 01:06:47 CET 2013

Leo Papadopoulos <leo <at> telecomcto.com> writes:

> ffmpeg -y -i
> liveRecording/telecomcto05BC3D96-5AAE-B957-D4A5-16B9D6DAF813.flv 
> -c:v libx264 -crf 23 -preset superfast -vsync 1 -r 25 -c:a aac 
> -strict -2 -b:a 16k -ar 16000 -ac 1 
> liveRecording/telecomcto16000-16k-superfast.mp4
> The above command gives me the file size I need which is about 2/3 the
> original FLV size, but it takes 1m44s to transcode.
> Is there anything I can do to transcode faster?

You could try ultrafast, the alternatives 
are a faster CPU / more cores or remux 
instead of re-encode (which may not work 
if your input is vfr and the output format 
(There should be faster aac encoders but 
this makes only a small part of the overall 
processing time.)

Carl Eugen

PS: Out of curiosity: Why do you need -vsync 1 ?

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