MKV's no longer open in QT

VLC will run .mkv files

 

I believe you have to open them with the "Perian (open with QuickTime)" application in the Open With menu.

But with fewer features. VLC also has inferior performance on HD videos compared to QuickTime/Perian on my system, although granted that probably isn't an issue on the Mac Pro.

 

Are the files opening in Quicktime X or in Quicktime Player 7 which is an optional install? QuickTime X doesn't work with Perian and some other codec packs.

 

.mkv on Quicktime7

Snow Leopard moves quicktime 7 to the utilities folder. To make it the default for .mkv files, select a .mkv file, right click, get info, open with "other" and navigate to Applications/Utilities?Quicktime7

 

Vlc is satisfactory for most media formats including mkv's but it doest have the fastest encoding ability

 

djblaze852002's instructions only work if you have QT7 installed; it's optional install on 10.6. If it's not there, here's Apple's instructions on installing it: http://support.apple.com/kb/HT3678

On a side note, while I used to be a VLC fan, if you just want to play videos MPlayer OSX Extended has a cleaner interface and on my system uses less CPU, skips around better, handles partly corrupt files better, and handles media served off a slow network connection better. The preferences are also drastically easier to understand, and it has a more Mac-like interface.

 

You might try Movist as well.

 

I'd recommend Mplayer OSX Extended as well, for these sort of files. VLC works as well, but I find Mplayer OSX Extended to have a much nicer interface.

If you have a serious need to play them in QTX, you'll need to install a 'helper' application (just stuff it on your hard drive somewhere), as outlined on Perian's forums. It essentially 'forces' QTX to know that it can play mkvs -- I haven't looked into why/how this happens, I just know it does.