A Phoronix reader tipped us off this morning about this code review on Chromium.org about moving the controlling of accelerated video decode support to the GPU blacklist. With the handling of video decode support being done from the GPU blacklist it would be easier and more streamlined to disable the blacklist and have easy access to VA-API video acceleration.
Back in 2012 I wrote about Google working on VA-API support in Chrome via VAVDA. Two years later, this code is still disabled by default. This Linux video acceleration support for Intel hardware and others isn't being enabled over concerns over bugs.
Ami Fischman explained in a bug comment yesterday, "There is a history of users disabling the blacklist (entirely) because they want a feature that is disabled. That destabilizes the entire browser, and users frequently forget about this action (and waste time trying to re-stabilize their browser later). If this landed I expect that sooner or later we'd get a rash of blog posts explaining how to get HW decode on linux 'for free' (by disabling the GPU blacklist) and the overall result for our Linux userbase would be a worse experience (because the blacklist will never be consulted on their system), not better (b/c they'll have HW acceleration of h.264 decode). This is a judgement call and I can certainly see how reasonable people can disagree, but this is my personal judgement."
Ami went on to imply that the VA-API Linux support will never be in good enough shape for Chrome, "We don't ship code we consider to be permanently 'experimental' or 'beta', only code we expect to be stable/production-quality eventually, if not at landing. This feature will never graduate to that status, so this CL is effectively shipping a feature that is known to be mostly-broken on most Linux installations."
Chrome developer Jorge Lucangeli Obes also commented on this report, "Supporting GPU features on Linux is a nightmare (I know from dealing with the GPU sandbox). Enabling this feature should come after thinking how we can make it available without making Chrome on Linux less stable."
There was then a proposal for introducing a GPU video decoding white-list to make it easier to mask systems with properly working VA-API support, but even that was shotdown due to varying graphics driver stacks, distributions, and hardware. The long story short is don't expect Google's Chrome/Chromium to have VA-API video acceleration support enabled by default anytime soon for Linux desktop users due to GPU driver concerns.