I just recently uninstalled all of the codecs I had and went through Andy VT's steps for installing his AntiPack codec pack.  Everything seems to work fine, except some hi-def mkv's are intemittently pixelated with big, green, splotchy pixels.  In a couple cases I had watched these videos before and they played fine before I switched codecs, but now aren't.  I can't figure out what codec I may be missing, or maybe which codec is misbeahving and causing this...  I do have MediaInfo installed and can analyze the files, but I'm not sure what I'm looking for, and haven't been able to determine a consistent property among the files.  To make matters a little more complicated, I recently switched out the NVIDIA video card in the PC for an ATI Radeon HD 4350 based video card.  I'm having other issues related to that card, but that's another thread...

Any ideas what could be causing this?  I was hoping it was a common symptom, but I couldn't find any mention of it in searching the threads here...

Thanks for the help!

I have no idea on whats causing this, but I had the same problem with my 1080p mkv's
I had tested the same files on a friends machine using same win7 version, he did not get the issue with his nvdia card.
I am using an ATI 4670HD, resolved the issue by using sharks codec package and Win7DSFilterTweaker to set the codecs.

diggityDawg:

I just recently uninstalled all of the codecs I had and went through Andy VT's steps for installing his AntiPack codec pack.  Everything seems to work fine, except some hi-def mkv's are intemittently pixelated with big, green, splotchy pixels.  In a couple cases I had watched these videos before and they played fine before I switched codecs, but now aren't.  I can't figure out what codec I may be missing, or maybe which codec is misbeahving and causing this...  I do have MediaInfo installed and can analyze the files, but I'm not sure what I'm looking for, and haven't been able to determine a consistent property among the files.  To make matters a little more complicated, I recently switched out the NVIDIA video card in the PC for an ATI Radeon HD 4350 based video card.  I'm having other issues related to that card, but that's another thread...

Any ideas what could be causing this?  I was hoping it was a common symptom, but I couldn't find any mention of it in searching the threads here...

Thanks for the help!

ATI cards have problems with certain HD video files encoded at weird bitrates, mostly the really high bitrates, when accelerated via DXVA. There is no known fix. Only thing you can do is use an nvidia card or a software decoder that doesn't use DXVA.

I have this problem with at least four 1080p and three 720p h264 files. The problem is basically what netscan02 said: ATI cards have issues with some higher bitrate files. I'm using the default video driver that comes on the Windows 7 DVD (which is apparently the same as the driver in the "Catalyst 9.5" package). I have not tried any of the newer Catalyst releases as I would rather let Windows Update handle driver updates instead of chasing new Catalyst releases.

My "solution" ended up being to disable DXVA for h264 using "DXVA Checker": http://bluesky23.hp.infoseek.co.jp/en/

All you have to do is download DXVA Checker, extract it somewhere, run it, hit the little button in the upper right corner under the close button (X), hit Video Acceleration Settings (or CTRL-V) and toggle "HWUVD_DisableH264". There should be a check mark in the checkbox to the left and a "1" in the Value column if you clicked in the right place.

Keep in mind that this disables DXVA for h264 streams so you're going to see quite a bit of CPU usage when playing ANY h264 files from now on. This may not be an issue as DXVA gets disabled if your files have subtitle streams anyway.

There may be other solutions but this one gets your stuff working without mucking about with 3rd party nonsense. (Well other than our favorite trilogy of Haali (for MKV's), AC3Filter (for DTS) and VSFilter (for subtitles).)

 I tried downloading DXVA checker like you said, when i hit Ctrl-V the window is blank.I dont know what to do man - any advice?

I noticed that too when I tried it on this Nvidia based laptop I'm currently using. I haven't figured out yet if it's because the tool doesn't work with Nvidia or if there's a bug in the newer versions of the tool.

What version are you using?

Try searching for an older version of dxvachecker (I'm using 1.9.0.0).

A friend downloaded a new version last week (version 2.0 I think) and ran into this problem, he got the older version and it worked ok.

I've never used dxvachecker with nvidia so it may be a different issue?

 

 Do you have a copy of this older version, i cant find it anywhere. Im using an ATI HD 5000 series card.

tigerec:

 Do you have a copy of this older version, i cant find it anywhere. Im using an ATI HD 5000 series card.

 

http://cid-b9f43836f7d8747f.skydrive.live.com/browse.aspx/.Public/MCE%20Stuff

i have had the same problem but i found a pretty good fix.. (short of going out and buying an nvidia card)... i have found that you can regsrv32 the media player classic codec (use this guide):

 

http://marcroberts.info/2009/11/dxva-and-mkv-in-windows-7/

 now.. if you enable the mpcvideodec.ax and use the Preferred Filter Tweaker for Windows 7 tool you will have setup media center to use the MPCvideodecoder... that decoder is smart enough to know whether or not to use DXVA on videos that it will work on.. at least it was for me... videos that would be blocky, the codec somehow knows it would be, and it uses software decoding.. hope that helps!