Dual Core needed for h.264??

[bazpaul]

Hey guys,

I read somewhere a while ago that YOU MUST have a dual core processor to play mp4 with h.264 encoding!! Is this totally true? or will video simply be choppy/pixelated???

I was planning on buying an old mini pc like this and installing XBMC for my parents to watch stuff.....however they will need it for h.264 content like new episodes of Boardwalk Empire and such!

what's the word on dual core's and h.264??????

thanks

[jman98]

If the video is standard definition (720x576 or smaller) that PC should be OK to play it back. But anything bigger will really start to tax the processor. The problem manifests itself as video that simply freezes so often that it's essentially unwatchable. Again - for single core CPU, if you wish to playback H.264 then you MUST keep the video at standard definition resolutions or lower. If you can get the video in Dixv/Xvid format then you can use higher resolutions as Dixv and Xvid don't require as much CPU power to decode as H.264 does.

[bazpaul]

weird!! so it can play h.264 it just depends on resolution!!! If i stick to 720p then I should be ok?

But im running XBMC on a raspberry pi and I was playing LOTR @ 1080p last night flawlessly and I dont think that's a dual core - any reason for this??

[jman98]

weird!! so it can play h.264 it just depends on resolution!!! If i stick to 720p then I should be ok?

But im running XBMC on a raspberry pi and I was playing LOTR @ 1080p last night flawlessly and I dont think that's a dual core - any reason for this??

Hell no, you should NOT be OK.

720p = 1280x720. That's bigger than 720x576.

Raspberry Pi has specialized video hardware that is optimized to allow H.264 1080p video playback.

[bazpaul]

awww dam - i just bought it!!!

Well at least it has a 7 day return policy!!

Do you think installing barebones an OS would improve load on the CPU - for example installing Xubuntu would tax the CPU less than Windows 7 running XBMC on this machine

[Hoser Rob]

Yes, speaking as an xubuntu user, xubuntu will load the cpu less than win7.

However xmbc is a very weighty program. I haven't used it much but I suspect it'd negate much of the advantage.

And I'd have to try playing on a single core in xubuntu before saying it'd help that much. I'd still want a dual core at least.

BTW xubuntu is light but not barebones. There's not one thing I ever did in win7 I can't do as well or better in xubuntu. Although I don't like the file manager xfce uses. Fortunately in linux you can easily install other ones.

[danzeb]

I'm running a Windows XP with a 3 Ghz Pentium 4 chip and Nvidia GT 430 graphics card. It is a single core but uses Hypertreading so it has some but not all the benefits of dual core. The Nvidia GT 430 is a big help. It plays h.264 720p fine.

[jman98]

If you can find a graphics card like danzeb suggests, you MIGHT be able to salvage this. All I can tell you is that I had a similar system I bought around 2005 and at the time I was never able to find a graphics card (it could only accept PCI inputs - no PCI-e) that could actually help process H.264 video. But that was some years ago. I can tell you that my system could attempt to play 720p video and with Divx and WMV it was fine. H.264 was iffy and mostly it didn't play without freezing enough to be unwatchable. But if you've got a graphics card that can actually help to do some of the video processing, it may be possible. But your costs go up in having to buy a graphics card that will actually be able to do this. The lack of PCI-e in my PC was what killed me. If what you bought also lacks a PCI-e slot, you're probably out of luck as I'm not aware of any PCI based video cards that can offload video processing.

H.264 is very CPU intensive. Running Linux instead of Windows won't help that because the playback constraints are the CPU, not the OS.

[jman98]

The link you provided says that that miniPC does have a PCI-e slot, so you're going to have to look into getting a card like danzeb suggests. You'll have to do some kind of setup (I have no idea what exactly) to get the card involved in all video processing if you're going to try to play back 720p or above H.264 files. 1080p may even be possible, but you'll have to try it and see.

[jagabo]

I seem to recall a 3 GHz P4 can play 720p24 h.264 with CPU decoding in most cases. 1080p24, no. Wait until you get it and try a few videos.

[bazpaul]

Thanks for all the info guys. Im hopeful it will work.

Yeh i plan to put a low profile pcie card into the comp. But how do i know what card is good for h264 processing????

what card specs should i look out for????

[jagabo]

Pretty much everything beyond an ATI 2400 or a Nvidia 6800 can play 1080p24 or 1080i30 if encoded with DXVA compatible settings. Which pretty much means any video card currently in production. Look for a 64 bit video memory bus for MCE smoothness*. Basically, any card over about $40 in the USA. If you download stuff from the internet you will probably come across videos that aren't DXVA compatible and will require CPU decoding.

* For example, we had an ATI 6450 with 32 bit memory. It could play 1080p video smoothly but Windows Media Center's program guide (overlaid in top of live video) was very sluggish.

[RabidDog]

There is nothing that states you need a dual core CPU to play back H264 .. its really just a matter of CPU horsepower .. what somebody means is you need a fairly powerful CPU to play back h264 if there is no outside assistance (eg Gfx card). Most modern CPUs have a hardware decode unit on the chip and this puts the decoding of h264 (and other h263 codecs like divx/xvid) into hardware. This is far more effective than doing it in software which is what has to be done if the CPU does not have this biult in.
All the modern Intel and AMD chips have hardware decode units built in. (from G530, A4-6000 thru to i7)
Server chips will not have this built in (Xeon, Opteron).
All modern graphics have it built in also.
This is why atom needed the ion gfx chipset to help out, on its own it was too weedy to play back bluray smoothly, whereas Amd LLano could do this easily due to its better video decode hardware.
That box you linked to is nice but it has a P4 processor which runs very hot, in a very small box (not good).
Also it lacks HDMI for which you need one of their gfx card upgrades, increasing the price