Revisit transcode parameters

[Ironman28]

Every couple of years we tweak the transcode parameters for the various formats we generate from uploads to Critical Commons, usually raising data rates to stay close to the quality of YouTube & Co. Maybe it's time to check in on our transcoder settings again and revise if necessary?

[ahelme]

As I've done before, I can do some research and testing into an revised sweet spot for CC's ffmpeg settings, and post them here.

[mgogoulos]

I don't have a picture here of what optimizations are needed!

[Ironman28]

I will let Anna respond to this. I don't know what is best. I just know we have routinely improved the quality of our transcoded videos every couple of years in order to stay comparable to other video sharing services.

[ahelme]

Actually, I don't believe I finally received access to the server? So I can't check what the current settings are...

I would suggest that we bump the current STANDARD setting to the current HIGH QUALITY setting.

(Standard currently looks quite poor compared to contemporary expectations in 2015)

And then bump the HIGH QUALITY setting up to something sensible above that.

Note this advice on ffmpeg wiki:
https://trac.ffmpeg.org/wiki/Encode/VP8
https://trac.ffmpeg.org/wiki/Encode/H.264