Created attachment 142707 [details]
Screen shot of YouTube video in Chromium, artifacts

I am attempting to play H.264 video in Chromium, using a fork of the current
beta (v71) that has a VAAPI patch applied. When playing the following video:

https://www.youtube.com/watch?v=oiSn2JuDQSc

I get the resulting video output, attached.

Using:

Description:    Ubuntu 18.10
Release:        18.10

chromium-browser 71.0.3578.62-0ubuntu1~ppa1~18.10.1

mesa-va-drivers 19.0~git1812040730.bacf84~oibaf~c

It should be possible to follow those to the patches used, but I don't think
that the Chromium patch is responsible for "misusing" VA-API, so much as the
radeonsi VA-API driver being broken in some way.

The artifact simply goes away if I disable h264ify, since it switches to VP9,
and thus software decoding.