# <Moved> HD x264 720p Playback Issues



## bkdude (Sep 29, 2008)

(I'm not entirely sure if this is the correct forum to be posting this in, but it seems appropriate.)

Hello. I've been having great problems trying to play a 720p video encoded in x264 on my computer, and I have tried many different ways of fixing it to no avail. I've tried using coreAVC and MPC combined with Haali Media Splitter and various audio codecs, and the outcome has always been the same.

1: The movie starts off fine and clear with no problems. (CPU usage ~ 30%)

2: Around 5-10 minutes into the movie, the CPU usage jerks to 100%, and frames drop, creating a jerky, unwatchable picture, while the audio continues without a problem, getting ahead of the picture.

No matter what combination of codecs or players I use, the result is almost always the same. I've completely removed all my added codecs before re-installing new ones, and I have no problems playing games or watching standard def. videos. I HAVE noticed though that my computer does have problems encoding DVDs for playback on external players, wheras a second computer I have with similar but slightly underpowered specs can encode in 1/6th of the time. I frequently defrag my hard drives and my drives have not been acting weird. Here are my specs:

XP Home (32 bit)
Pentium D 3.2 Ghz
GIGABYTE GA-8I915P Duo w/ onboard sound
EVGA nVidia GeForce 8600 GTS
4 Gb DDR2 533 RAM
250 Gb WD SATA Primary Drive
500 Gb WD SATA Secondary Drive
1680 x 1050 ACER LCD Display (60 hz)

And for those of you who wish to know the specs of my second computer that can somehow encode DVDs faster:

XP Home (32 bit)
Pentium D 2.8 Ghz
AsRock Wolfdale MB
2 Gb DDR2 533 RAM
GIGABYTE nVidia GeForce 7600 GT
200 GB PATA HD
(this computer isn't currently in operation as its PSU died. i need to buy a new one for it )

Here are my questions.

1: What codecs/players should I download and use, and in what order should I install them?

2: How should I optimize them to play x264 720p videos on my computer?

*Edit-
The video in question is packaged in .MKV


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## bkdude (Sep 29, 2008)

*Edit

I've tried K-lite codec pack including the following codecs:

ffdshow audio + video
Haali splitter
Other ect codecs

The result is the same. Playback works for a bit, and then CPU usage spikes and i get the slideshow effect while audio continues to work.

Can someone please help me with this...? :-/


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## blah789 (Aug 25, 2008)

May I ask if the scenes where it starts to spike/jump to 100% CPU usage high-motion scenes? As you probably know, H.264-family codecs are insanely computing-intensive - and even more so in high definition (and generally best handled by dedicated hardware decoders - at least for the near future). I personally don't know how the ability of current CPU's to decode stands in relation to the frame rate and resolution at present (for example when I had my K6-2 500, it worked fine for most decoding, but with DivX 5 at 640x480, it would start dropping frames and freezing and 100% CPU usage - when I got an Athlon XP that problem went away - down to 15-30% CPU usage)
I'd ask at doom9.org to see what other users are getting for that CPU and those resolutions. If your PC is underpowered, perhaps getting a graphics card with HD support might help (though I'd understand your reluctance as you have a pretty high-end card already).


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## blah789 (Aug 25, 2008)

OK I looked some more at the specs of the 8600 GTS and it appears to support HD VC-1 and H.264 decoding though PureVideo. It might even come with the PureVideo (software) DVD Player from nVidia - don't know if it will support x264 specifically though. If your software/drivers CD came with the DVD player, try installing it and seeing if it works better.
If not you'd have to find a setting in ffdshow that somehow enables PureVideo so as to offload x264 decoding from the CPU to the GPU.
If you can't find such a setting in the ffdshow settings, try VLC Media Player (http://www.videolan.org). It uses the same libraries as ffdshow (libavcodec), but is a standalone player (whereas ffdshow is a filter). Perhaps VLC will have such settings somewhere in their menu.

And finally make sure you don't have hardware acceleration or overlays turned off or anything like that.


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## blah789 (Aug 25, 2008)

This post
http://forum.videolan.org/viewtopic.php?f=2&t=42328&start=15
suggests VideoLan requires you set the decoding explicitly to DirectX, not default, not Direct3D.
In VLC 0.9 they've arranged the menus a bit. It's in tools, preferences, All (as opposed to simple, at the bottom), video, output module. Probably DirectX Video Output on that menu.
Also make sure you have up-to-date drivers for the 8600 GTS to make the HD functions available to the system.


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## bkdude (Sep 29, 2008)

Well, my computer just got a virus last night, and I felt like switching to Vista anyway, so now I'm running vista. I'll be sure to try out your helpful advice either tonight or tommorow. Thanks loads for taking the time in researching this stuff. I'll tell you if any of it works either tonight or tommorow.

And the two 720p videos i have tried have always ran 100% smooth with no dropped frames even through the most contrasting parts of the films, yet after 5-10 minutes, it would always spike and give me the slideshow effect. I'll be sure to try the things you recommended. I have updated the graphic drivers, with the newest version just released 5 days ago


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## bkdude (Sep 29, 2008)

Well, I tried the things you suggested with mixed results. I tried installing that nvidia realvideo, but it dosen't show any signs of being activated, so I'm not entirely sure about that decoder. I then tried using the latest version of VLC following the instructions on that forum post, and it worked better than it normally does, but after 10 minutes theres about a second chip-in.

So, i resorted to using some codec setup i had that i thought didn't work correctly, and it seems to work pretty well. I don't notice any skipped frames during playback (i think skipped frames when seeking is inevitable), and i had it running for about 20 minutes, so i think i'm just going to stick with this:

Media Player Classic - Homecinema using Media Player Classic Video Decoder.

I had this running a few days ago on XP, and the CPU usage was around 5-7%, and i had it on for about an hour, but after this it began tweaking out :-/

Now the CPU usage stays around 30-70%, and the video plays fine without any problems. I'll keep you updated if theres any other hitches but in the meantime it works alright. It does use DXVA which is some hardware accelerator that works with my graphics card. I'm not entirely sure.


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