[fab67]

For info, I build libvpx and enable it in ffmpeg ( --disable-decoder=vp9 --enable-libvpx ) instead of built-in vp9 decoder, it's a little faster but not enough to play vp9 files at 720p or 1080p.

Does it make use of all cores?
Any view on how much faster it is? E.g. if you play an SD file what is the percentage CPU with default ffmpeg and libvpx?

I made some benchmark with ffmpeg : http://pastebin.com/6rUdkuJ3
with 4 threads libvpx-vp9 should be ~2 times faster (22 fps) than ffmpeg-vp9 (12 fps) (libvpx-vp9 with 1 thread -> 10fps )

And for 720p : libvpx-vp9 : 37 fps and ffmpeg-vp9 : 17 fps

But I think the problem is that the players in kodi doesn't enable/use 4 threads with libvpx-vp9 because 720p doesn't play smooth.