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Hardware-Based Video Acceleration Coming To Linux
sammydee writes "Phoronix reports that GPU based video decoding acceleration will be implemented in Gallium3d sometime this year. Drivers currently using Gallium3d include the open source nouveau driver for NVIDIA cards and experimental Intel GMA drivers. This is definitely good news for anybody who has ever tried to play high-definition 1080p content on any CPU older than about a year."
nVidia's binary drivers and X.org's Intel drivers have had XvMC support for well over a year. I've been using both card successfully with Xine and accelerated 1080p video. I think the news here is that the nouveau project is catching up, but that's hardly clear from the article.
Interested in open source engine management for your Subaru?
This is apparently a google summer of code project.
While I am hopeful, let's not write this one on stone until it's released.
Help! I'm a slashdot refugee.
Xine has supported hardware accelerated DVD video (MPEG1/2) decoding using EM8300 based cards like Sigma Design's Holywood+ and Creative's DXR3, since about 2000.
(But that was done using an ad-hoc module inside Xine, not using generic APIs like XvMC or the future Gallium3d video)
The Gallium3D Video API is a good news, because it'll probably be able to address shortcommings that XvMC has.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Basically history is repeating itself. When DVDs first came out, MPEG-2 decoding was done on the CPU. Then video cards started having hardware supported MPEG-2 decoding. Now that we have the HD video codecs (AVC, VC-1, hires MPEG-2), we went back to square one (especially with AVC and VC-1, which require some pretty heavy lifting). In the past couple of years, video cards have added hardware support for those tasks, which otherwise would max out a fairly decent processor (~2GHz dualcore) trying to decode a high bitrate 1080p stream.
This guy's the limit!
I think the point is that it is CPU dependent if you don't have any assistance from video hardware acceleration, as is the case if your video drivers are incomplete.
which is totally what she said
XvMC does only accelerate MPEG-2, and not many use it, because the de-interlacing you can get sucks. And for MPEG-2, you usually don't need hardware acceleration anyway.
nVidia, like ATI, are moving away from video overlays and have some pretty nice GPU-based video decoding built into their cards using the GPU (most of it probably implemented as shader programs).
But you can't use any of that with linux, you are basically down to hardware video scaling, which the newest cards no longer really support.
It is high time for a new, industry standard API for video. I hope that's what they are doing.
Playing a video is no problem.
The problem is that a high-bitrate 1080p video stream requires a lot of CPU time to decode, and then you have to transfer the whole uncompressed frame out to the video card.
Unless you have a really high-end CPU, there are no Windows-based video players capable of doing this with just software. They all require some kind of hardware acceleration. The specs for all this are nicely closed up, and are known only to Microsoft, video card manufacturers, and the few companies that implement video decoders (which is probably Microsoft again).
Video card manufacturers like nVidia have refused to implement any kind of video decoding in their Linux drivers until there's an appropriate spec. They won't tell anyone what they're hardware is actually capable of, so nobody else can write a spec. We can't even reference Microsoft's basic design, because it's all closed off and secret.
Oh, and most of it doesn't even work properly in Windows either. I've never managed to get it to work at all, and benchmarks I've seen seem to suggest that it's really only offloading 10% or so of the workload. Just enough to make the difference between working and not working, but not as much as it could be.
The Gallium guys are planning to implement the entire thing in their video drivers, using only the 3D capabilities that video cards are known to have. That neatly bypasses the whole thing, but required that we have a single base driver to work with (which Gallium provides), and one or more video drivers actually using it (which, again, Gallium provides).
I kind of hope that Gallium implements something similar to nVidia's CUDA - a programming model for running stuff on graphics cards that doesn't rely on graphics-related stuff like textures or polygons. That way, we'd have a way to implement different kinds of video decoders, encoders, or even things like physics simulations. Bonus points if it can be made compatible with something available on Windows...
That said... Linux video players tend to be a hell of a lot quicker than Windows video players. I've played videos in Linux that were impossible to play in Linux.
If you are running Windows and using the manufacturer's drivers for a relatively recent (last few years) video card, then yeah, everything should be peachy. But if you are using open source video card drivers under Linux then good luck. Even with the proprietary Nvidia driver, highdef video playback can max out a fairly new CPU. http://www.mythtv.org/wiki/index.php/HD_Playback_Reports will give you an indication about the type of setup you need to get HD video playback to work.
VLC works great for me on the windows boxes I use for my home media system. Plays HD contect fine.
The one in the living room is a Core2 1.8 with 1.5 of ram with an ATI 2400 HD card and no problems with HD acceleration in XP.
I do not game much, so this 59 dollar HD card has been great.
Workstation is same setup, with two gigs of ram and vista, no problems with HD video.
Server side is a linux box which runs headless. /all rooms have a pc attached to the tv /my guests can surf the web, watch movies, videos /or grab a wireless rumblepad and play any mame game of their choosing.
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