I want to start using the WebM format and the VP9 codec for my YouTube videos. I know that with good compression comes slow speed, but FFmpeg only uses 1 of my 8 cores. I've tried using -threads 8 in my command, but FFmpeg seems to ignore it. From what I've read, the VP9 encoder should support multiple threads. What can I do to get this to work?
FFmpeg version 2.7.2-1build1
libvpx1 version 1.3.0-3ubuntu1
libvpx2 version 1.4.0-4
Command used:
ffmpeg -i input.mp4 -c:v libvpx-vp9 -crf 10 -b:v 5000k -c:a libvorbis output.webm
While we're at it, do I need both libvpx packages installed? libvpx2 has the Ubuntu icon next to it in Synaptic, so I'm guessing the other one is a leftover from upgrading to 15.10?
-threads 0
should use all your cores. You can try -threads 8 or -threads 16 . Order of options is important, so put the -threads option before the input (-i input.mp4) option.-i
will be applied to the input (the decoder or demuxer).