MKV: High CPU usage when not transcoding?

[cncb]

I have the LAV splitter/filters installed on my PC and when I try to play an MKV (H264 with AC3 audio) on the XBOX 360 E it uses about 80% of the CPU. There is no transcoding going on as far as I can tell. An MKV with VC1 only uses around 14% CPU. Any ideas what might be going on? Thanks.

[glugglug]

Almost certainly transcoding if the CPU is that high, especially if task manager shows it to be wmplayer instances. Honestly 14% CPU is pretty high unless your CPU is very weak.

One really stupid thing I have seen is that WMC will transcode both video and audio streams just because the audio codec is not supported by the extender. Are you sure the MKV has AC3 audio? If there are multiple audio streams (i.e. DTS) try deleting the others.

[cncb]

I'm sure the MKV just has AC3 audio. Most of the CPU usage is in the "Media Foundation Protected Pipeline EXE" process. How do you keep WMC from transcoding (I actually thought it just did the splitting and you would have to do something special for it to transcode)??

[cncb]

Anyone have any suggestions in how to prevent transcoding? I am using Windows 8.1 and when I added the extender I had to manually add an entry to the registry to have it recognize MKV files. For some reason it did not automatically add it even though MKV was recognized and played properly on the PC before I added the extender. Maybe this has something to do with it?

[glugglug]

Hmm, based on the thread TheOsbourneFamily started on not having bitrate restrictions in 8.1, I think this might be a new feature in 8.1?

The XBOX 360 officially supports H.264 only up to 10 Mbps (Realistically more like up to 15-16Mbps before it chokes). Maybe the 8.1 streaming code is aware of the bitrate limit and transcodes if the source video is above this?

[Shark007]

I have the LAV splitter/filters installed on my PC and when I try to play an MKV (H264 with AC3 audio) on the XBOX 360 E it uses about 80% of the CPU. There is no transcoding going on as far as I can tell. An MKV with VC1 only uses around 14% CPU. Any ideas what might be going on? Thanks.

you issue is related to your codec installation.
If you remove LAV and install the Shark9007 codecs, your issues will be solved.
Keep in mind, 64bit systems also require the x64Components as well as the 32bit codecs.

[Socketman]

I had similar issues. Since I don't like reading instructions I made myself a headache. Make sure you have UAC at default before installing the shark package and you should be good to go.

[cncb]

I always leave UAC on and I may try the shark package. However, I found that a remux to WTV seems to provide solid playback without any transcoding so I may just stick with that. Thanks, all, for the help.

[Socketman]

Glad to hear you found a way to enjoy your movies. FWIW using an mkv container does not use any transcoding either. All I have ever needed is the Divx Splitter .