After wasting hours riffling around the internet to try and find a simple and reliable solution for playing mkv files in Windows 7 Media Center, under the x64 bit version.
On paper the shift from the 32 to 64bit version of Windows is pretty painless, as there’s much improved driver support these days (as anyone who tried the x64 version of XP can attest to)
The main pain point is that even in the x64 version of windows, Media Player still defaults to the 32bit version, which is great for compatibility with the existing codecs, it also draws you into a confusing situation where a file will play in Media Player and refuse point blank to play in Media Center.
This is due to Media Center being a native x64 application, so requiring x64 codecs. Forunately things had improved over the last few months in this regard, now there are two free applications I can recommend to add .mkv support…
Divx Lab’s MKV Codec
The Divx Lab’s project aims to utilize the Windows Media Foundation to enable playback of the popular MKV format on both the main Media Center machine as well as extenders. Not only does this mean support for extenders but it could also very well mean the end to playing with various codec package settings to tweak the audio/video settings to match the output of the default Media Center playback.
via Playing MKVs with Media Foundation and Divx Labs.
Haali’s Matroska Splitter
Haali’s Matroska splitter is one of the most popular MKV splitters available for Media Center users who run custom codec setups. Little secret though, there’s a beta Haali splitter available for x64 systems and it works great on Windows 7 systems.
via Finding Haali’s x64 Splitter Beta
AC3Filter
AC3Filter is a high quality free audio decoder and processor filter. It allows media players to playback movies with AC3 and DTS audio tracks. Also it can process any audio track, much of processing options allows to adjust the sound in almost any way. It is possible to upmix any audio source to 6 channels. Filter can do multi-channel and digital (SPDIF) output. It can encode any audio source to AC3 on-the-fly and send it over SPDIF to the receiver. Download the full version for x64 support.
via Ac3filter
MKV Thumbnails in Windows
Finally if you want to enable thumbnails of videos within Media Center and Windows Explorer, you will need to add some information to your systems registry.
Download the x86 version here or x64 version here and more information can be found at hack7mc.com
Big thanks to the always brilliant Hacking Windows 7 Media Center for the in depth and up to date codec information