Bug 3381

I've really enjoyed using the newer ffmpeg builds in rawhide.  I've used the 2.3.3 build and the 2.3.4 builds on Fedora 21 pre-beta.  I'm mainly giving them a spin because of improved support for webm with vp9/opus.  vp9 encoding is still very slow but that is to be expected because even Google hasn't optimized their encoder yet.

I still produce webm with vp8/ogg for most things... and the encoding speed on that has regressed to be 1/4 to 1/3 what it used to be... compared to say ffmpeg 2.1.5 in Fedora 20.  To the best of my knowledge, both Fedora 20 and Fedora 21 are using libvpx 1.3.0.

My guess is that the simple flags I'm using... some of the defaults for vp9 are being used and slowing down encoding speed.  Here's a typical command line:

ffmpeg -y -i source.mp4 -f webm -b:v 800k -b:a 96k -vf scale=720:-1 -ac 2 -sn output.webm

When I want to encode vp9/opus I do something like:

ffmpeg -y -i source.mp4 -f webm -vcodec libvpx-vp9 -acodec libopus -b:v 400k -b:a 64k -vf scale=720:-1 -ac 2 -sn output-vp9.webm

Using those two samples... vp8 encoding is probably twice as fast as vp9... but still a LOT slower than it has been in past versions.

Any clues?