Arch Linux

kaslusimoes

Member

Registered: 2013-12-19

Posts: 51

[SOLVED] Which value to set VDPAU_DRIVER?

Hey,

I've been reading ArchWiki's page on VDPAU just as a curiosity (https://wiki.archlinux.org/index.php/VD … figuration) but couldn't quite understand to what value should I set my VDPAU_DRIVER (or even if should set it to something or just let it be).

The thing is that the wiki says that, if I'm using Intel Graphics, I should set it to "va_gl", but when I issue `grep -i vdpau /var/log/Xorg.0.log` it returns me "VDPAU driver: i965"
So I keep wondering which one should I set: "va_gl" or "i965"? Is i965 even a possible choice or am I understanding it wrongly?

Sorry about anything, I'm really not so sure about what's VDPAU for.

Last edited by kaslusimoes (2015-01-30 12:03:41)

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: [SOLVED] Which value to set VDPAU_DRIVER?

Intel doesn't provide VDPAU, only VAAPI (the package is libva-intel-driver). So you should use that, it's supported by pretty much everything - mpv, VLC, gst-vaapi, Kodi. There's just one application that doesn't support VAAPI, and that's Flash. For that one, you install libvdpau-va-gl and set VDPAU_DRIVER to va_gl.

Yeah, the wiki is waaaay too complicated when it comes to all this, it confuses more than it helps.

bstaletic

Member

Registered: 2014-02-02

Posts: 658

Re: [SOLVED] Which value to set VDPAU_DRIVER?

That command should be used if you aresetting up vdpau with radeon cards, in any other case use what wiki told you to use.

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kaslusimoes

Member

Registered: 2013-12-19

Posts: 51

Re: [SOLVED] Which value to set VDPAU_DRIVER?

@Gusar @bstaletic Thank you very much!

But what is that i965 for, anyway?

$ grep -i vdpau /var/log/Xorg.0.log
[   352.925] (II) intel(0): [DRI2]   VDPAU driver: i965

[EDIT]
Also, when I issue vainfo, I get this i965 again:

vainfo: Driver version: Intel i965 driver for Intel(R) Ivybridge Mobile - 1.5.0

If someone could please explain me some more about VA-API and VDPAU, I'd very very pleased. Tried to get some information from the wiki and wikipedia but it couldn't help me get less confused

Last edited by kaslusimoes (2015-01-28 14:37:44)

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: [SOLVED] Which value to set VDPAU_DRIVER?

VDPAU and VAAPI are application programming interfaces (API) to access hardware video decoders. To make hardware video decoding work, the API needs to be implemented in two places - the graphics driver and the video player. On the driver side, there are those which implement VAAPI (intel and catalyst), VDPAU (nvidia proprietary driver), both VAAPI and VDPAU (nouveau and radeon). On the player side, with the exception of Flash, players nowadays implement both.

Then you have wrappers, they translate from one API to another: libvdpau-va-gl and libva-vdpau-driver. They're needed when an application implements one API, but the graphics driver implements the other. Nowadays there's just one scenario where this is needed - using Flash on the intel/catalyst drivers requires libvdpau-va-gl. That's it, beyond that the use of wrappers should be avoided as they're just a potential source of issues.

That line in the X log is very misleading. It just sets the VDPAU driver name, but it does not mean that the driver actually implements VDPAU!

Edit: I've been looking at this stuff yesterday and learned that nouveau does not support VAAPI. VAAPI in mesa is implemented as a gallium state tracker, so i thought all gallium drivers support it. But it turns out only r600 and radeonsi do. Not that big a deal, nouveau with VDPAU should work well where supported, see here for more info.

Last edited by Gusar (2015-03-24 13:52:11)

kaslusimoes

Member

Registered: 2013-12-19

Posts: 51

Re: [SOLVED] Which value to set VDPAU_DRIVER?

Thank you very much Gusar, that was really helpful!

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: [SOLVED] Which value to set VDPAU_DRIVER?

I just noticed something very interesting when looking at the xf86-video-intel git log: Set the vdpau driver to va_gl. This means that starting from the next xf86-video-intel driver release, the VDPAU driver name will be set to va_gl instead of i965/i915, so there will be no need to set any environment variables anymore, and no misleading message in the X log.

kaslusimoes

Member

Registered: 2013-12-19

Posts: 51

Re: [SOLVED] Which value to set VDPAU_DRIVER?

Interesting!