XiphQT Allows the playback of Ogg Vorbis (.ogg) .ogm and FLAC files.
Download the latest decoder. (Make sure you download the .dmg marked 'only decoders'!)
Copy the .dmg disc image to your Apple TV
scp xiph-qt-decoders-0.1.8.dmg frontrow@appletv:
Login to your Apple TV via ssh. Mount the disc image
sudo hdiutil mount xiph-qt-decoders-0.1.8.dmg
The disc image will now be mounted in your /Volumes directory. eg: /Volumes/Xiph 0.1.8/
Make the file system read-write
sudo mount -uw /
Copy the Xiph components to your /Library/Components/ directory:
sudo cp -r "/Volumes/XiphQT 0.1.8/XiphQT (decoders).component" /Library/Components/
Make the file system read-only
sudo mount -ur /
Reboot your AppleTV (Is this necessary?)
Update 03-Jan-2009 - After following the above steps on a 2.1 AppleTV, I had to then perform the following to get FLAC files to play in ATVFiles.
Download flac_import_0.5b1_p0.1.dmg from http://people.xiph.org/~arek/flac_import/ and transfer it over to your AppleTV using the same method as for the XiphQT dmg.
sudo hdiutil mount flac_import_0.5b1_p0.1.dmg
Change into it's mounted location:
cd /Volumes/FLAC\ Importer\ \(0.5b1\ +\ XiphQT\ patch\ 0.1\)/
Copy the contained component to your AppleTV's /Library/Quicktime directory:
sudo cp -r FLACImport.component /Library/QuickTime/
Then restart finder or reboot your AppleTV:
If you still have troubles playing your FLAC files, you might need to look at this thread for more details, check out this thread: http://forum.awkwardtv.org/viewtopic.php?f=11&t=1315