0A temporary workaround for the ATI / 7MC / BBC-HD problems

-update-
This issue has now been fixed by a driver update from ati. For more info see the [int­link id=“48” type=“post”]latest article[/intlink] on the issue

There appears to be an incom­pat­ib­il­ity between the Microsoft codecs in Win­dows 7 and BBC-HD (and oth­er broad­casters too I under­stand). This causes some image cor­rup­tion on all plat­forms I have tested, but on ATI hard­ware it res­ults in con­tinu­ous cor­rup­tion which renders BBC-HD unwatch­able. For any­one look­ing for a solu­tion to this prob­lem keep an eye on the Microsoft know­ledge­base art­icle KB2008334. In the mean­time, there is a work-around, as long as you have a suf­fi­ciently power­ful CPU — dis­abling GPU accel­er­ated H.264 decod­ing. To do this requires a registry edit…

• Run reged­it
• Browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Video
• In video there will be sev­er­al sub­keys. One of these is for your graph­ics card. To loc­ate it you will have to look through each in turn — each will have a video folder inside it. The “ser­vice” value inside the video key is the clue you need — I have sev­er­al that start RDP which is pre­sum­ably related to remote desktop so they’re not right. I also have one which is called atikm­d­ag. This is the one!
• When you’ve found the cor­rect sub­key of video expand the key 0000 (if you’ve got the wrong one you prob­ably wont be able to expand 0000)
• Expand “UMD” and then “DXVA”
• Cre­ate a new string value called VForceUVDH264
• set the value to 0
• Reboot. Test BBC-HD. You will get 5–10 seconds of ini­tial cor­rup­tion but play­back should then become nor­mal and should remain that way thereafter

This tweak will dis­able gpu accel­er­a­tion of play­back of all H.264 files — so if you have a blu-ray col­lec­tion you’re going to be decod­ing with the CPU — expect much high­er CPU usage. Any mod­ern dual-core CPU should be plenty cap­able however.

Once Microsoft issue a fix for this prob­lem simply go back into reged­it and delete the key to restore nor­mal functioning.