Posts: 278
Joined: Feb 2008
Reputation:
2
touser
Senior Member
Posts: 278
Hi everyone,
I'm hoping someone can help explain the point of going through the trouble of setting up hardware gpu video decoding, specifically on cpu's that are plenty powerful to decode everything you throw at them in software (intel i3, etc.). I've read through endless threads of people fighting to get intel gpu decoding working in linux on cpu's that can easily play back 1080P content without breaking a sweat in software. What is the up side, especially in linux where it can be a chore to get proper support? I must be missing some obvious benefits? Thanks!
Posts: 31,445
Joined: Jan 2011
2012-06-26, 07:21
(This post was last modified: 2012-06-26, 07:22 by Ned Scott.)
Because low-power processors are also getting more popular (ATOM, AMD's APUs, etc). Also, new video codecs will come out that are even more taxing (h.265 will come out in about a year and will be very hard to decode on most modern processors. It will need hardware decoding support to really take off).
Then there's ARM processors. There's no way those are going to be serious HTPC contenders without hardware decoding. Thanks to ARM processors and hardware decoding, we're very close to having $50 and less HTPCs that can handle a full bluray rip (even in 3D, so 1080+).
Then there's portables. Anyone with a laptop will tell you that hardware video decoding is a must if you want your battery to last.
Posts: 6,339
Joined: Jul 2010
Reputation:
116
artrafael
Team-XBMC Forum Moderator
Posts: 6,339
The ability to use less power-hungry hardware to save on space/power requirements and to realize significant reductions in noise/heat generation. Check out the Raspberry Pi and Allwinner A10 threads to see how, by using HW decoding, a tiny device with an "underpowered" CPU potentially can be used to run XBMC and playback 1080p content.
Posts: 5,292
Joined: Jun 2006
Reputation:
62
Jezz_X
Team-XBMC Skinner
Posts: 5,292
because its a cool buzz word to put into a feature list
now too sit back and watch the line
Posts: 83
Joined: May 2011
Reputation:
0
Becuase low powered netops like the Acer revo area very popular option as a htpc. They will play full hd using its ion gpu, but will struggle on most things if using just the atom cpu's. For me GPU decoding is a must.
Posts: 1,483
Joined: Aug 2010
All true, but for me a big dis-advantage to GPU decoding is that most stuff is happening within closed-sourced drivers. In the old days a CPU & FFMPEG did most of the work for free. With the rise of GPU decoding, functionalities are once more locked down and coupled to hardware.
Posts: 12,706
Joined: Nov 2003
Reputation:
129
spiff
Team-Kodi Member
Posts: 12,706
good thing you have a choice.
Posts: 1,483
Joined: Aug 2010
In many ways, general purpose computing and free/open source software (FOSS) go hand in hand. It's something to think about for a FOSS project like XBMC since FOSS HTPC <> General purpose computing.
But yes, you still can choose which hardware you'll buy.
Posts: 278
Joined: Feb 2008
Reputation:
2
touser
Senior Member
Posts: 278
Thank you for the replies! I completely understand the need on ARM and low powered x86 machines (atom + ion, etc.). What i'm really curious about is say i buy an i3-2xxxx processor that idles ~8 watts with a max TDP of ~17W. Apparently these can handle 1080P h.264 no sweat in software, 17W is peanuts for max TDP and likely the cpu won't get anywhere near that just decoding video anyways. For that exact use case scenario is it even worth bothering with gpu decoding if all I care about is smooth 1080P h.264 playback?
Posts: 31,445
Joined: Jan 2011
Not really :D
CPU decoding can even give you (in theory) better picture quality, as a software decoder is updatable, while a hardware decoder isn't.
Posts: 31,445
Joined: Jan 2011
An i3 should be enough to CPU decode 1080 h.264 without frame dropping, though. My 2009 core2duo can do as much.
Posts: 1,483
Joined: Aug 2010
A little more info on ffmpeg being single threaded:
http://forum.xbmc.org/showthread.php?tid=130180