Nvidia / GPU Video Acceleration

[Shibblet]

I have been following all of the directions on how to get your "Chromium" Browser to work with GPU Acceleration Here:, as well as looking at Arch to see how it's done, or if any of it is applicable, Here:

I have a GTX 780ti, and I know it only works with the "h264ify" Chromium Extension, and with H.264 Video. It does not work with VP9 via Hardware, so this will be H.264 only.
I did all of these tests with the "Big Buck Bunny" video at 1080p and 60fps.

And I have been able to get it to work... or at least it "says" that it does.

Youtube.png

Here is my GPU Monitor when decoding H.264 via YouTube

BBB h264.png

Then I also downloaded the video, and played it back in VLC which is set for VDPAU output.

BBB VLC.png

As you can see, there is more more CPU usage with H.264, but no where near as much as when played in VLC with VDPAU... However, the GPU Information is quite different between the two...

Here is H.264 playback in YouTube:

GPU h264.png

And here is the VDPAU Playback in VLC:

GPU VDPAU.png

Anyway, with all of that information, I am not really sure if I am getting HW Acceleration with video playback at all. Any ideas?

[Yellow Pasque]

You're still using a VA-API->VDPAU wrapper in the browser, so it's not surprising there's some overhead there. It's not going to play as efficiently as native VDPAU. The question is whether it's better than software/CPU accel. I'm not sure what you are getting at here...

[Shibblet]

You're still using a VA-API->VDPAU wrapper in the browser, so it's not surprising there's some overhead there. It's not going to play as efficiently as native VDPAU. The question is whether it's better than software/CPU accel. I'm not sure what you are getting at here...

Here is what it looks like with Video Acceleration on:

BBB h264.png

And here is what it looks like without Video Acceleration:

h264 no accel.png

Not much of a difference on the CPU. So, I guess what I am getting at is... Does this actually work, or is it just smoke and mirrors?

[CatKiller]

Video decoding is a set of (usually vector) calculations.

You can do them on any CPU, in software. To hit the speed requirements of doing them in realtime, the processor has to be running quite fast.

But! CPUs have had specific ASICs and co-processors for doing fast, efficient vector calculations for a long time; that's what AVX, SSE and 3DNow! are all about.

But! GPUs are also really good at doing fast, efficient vector calculations, even more so than CPU co-processors.

But! GPUs can have their own media decoding co-processors which are even faster and even more efficient.

All of these except the very first one are "hardware accelerated." Both the last two are "GPU accelerated."

Your output when you were using the "Video Engine" is when you were using your GPU's media decoding block. The output when you weren't using the "Video Engine" is when you were using just the vector calculation capabilities of your GPU.

[Shibblet]

Your output when you were using the "Video Engine" is when you were using your GPU's media decoding block. The output when you weren't using the "Video Engine" is when you were using just the vector calculation capabilities of your GPU.

So, I want to make sure I am hearing you correctly. There is really no reason to go through all of this "setup" stuff in order to get Hardware Decoding in the Browser since the GPU is going to be used for vector calculations anyway?

One claims to be "Hardware Accelerated," the other is not. Both use roughly the same amount of CPU.

So, whether or not HW Acceleration is functioning, it's still going to use the same amount of CPU either way?

What's the point of HW Acceleration then?

[CatKiller]

What's the point of HW Acceleration then?

Battery life. On the desktop it doesn't matter that much - you won't generally want to do it entirely in software, since a slow CPU can't keep up, but as long as you've cleared that hurdle so that it actually works, there's not much advantage in going further. On a mobile device, though, using the dedicated media decoding blocks makes a significant different to power draw.

[Shibblet]

Battery life. On the desktop it doesn't matter that much - you won't generally want to do it entirely in software, since a slow CPU can't keep up, but as long as you've cleared that hurdle so that it actually works, there's not much advantage in going further. On a mobile device, though, using the dedicated media decoding blocks makes a significant different to power draw.

Thanks! That's probably the best answer I have found yet.

I have done some serious internet searching, and most of the answers seem to be that it's a major difference. Whereas everything I have done only comes up to a minor difference...

Second question: I am curious how this works in Windows. I have some friends who claim their graphics cards take the entire process over, and they get significantly better performance in these cases. Any ideas why this would be so different in Linux?

[CatKiller]

Second question: I am curious how this works in Windows. I have some friends who claim their graphics cards take the entire process over, and they get significantly better performance in these cases. Any ideas why this would be so different in Linux?

Market share and the iron grip of Microsoft.

Microsoft can mandate that all hardware has to use whatever interface Microsoft likes, and browsers have to support that because of Windows' market share. On Linux, Nvidia uses VDPAU and Intel went with their own VA-API, and browser makers haven't bothered supporting either at all until very recently because of the small market share.

[Shibblet]

Market share and the iron grip of Microsoft.

Microsoft can mandate that all hardware has to use whatever interface Microsoft likes, and browsers have to support that because of Windows' market share. On Linux, Nvidia uses VDPAU and Intel went with their own VA-API, and browser makers haven't bothered supporting either at all until very recently because of the small market share.

Gotcha.

So, in essence, Linux (in general) has "Hardware 'Assisted' Acceleration."

These are the things that cause Linux users to go "back" to Windows. Things like drivers not working correctly and hardware acceleration issues. I don't see software really being a big issue much anymore. Even Windows users are aware of replacement software, such as GIMP for Photoshop, and Only Office for MS Office...

Anyway... I am using a desktop, and the gains with "HW Assist" are minimal, as you can see in the screenshots.

How hard would it be to use VDPAU for Video in the Browser instead of VAAPI?

[CatKiller]

How hard would it be to use VDPAU for Video in the Browser instead of VAAPI?

All you'd need to do is convince the browser makers to wire up support for VDPAU. In the meantime there's a VA-API/VDPAU wrapper that turns VA-API calls into VDPAU ones, but it's apparently a bit finicky.