See the post at the bottom of the link above. In a nutshell, things like Perian that used to allow Quick Look (not to be confused with the QuickTime Player) to preview a bunch of video formats got hosed when Apple switched over to "AV Foundation" or something.
Considering how many less video formats work with Quick Look after "upgrading" from Snow Leopard to Mavericks, I personally consider it "depreciated" at least in principle.
Quite a lot of Mac users (especially those that work with a lot of video formats) have been waiting for something to fix this Quick Look issue for some years now.
The best you can do at the moment is install this to see thumbnails in Quick Look for some video formats:
https://developer.apple.com/library/mac/technotes/tn2300/_in...
Here's more info on the change Apple made here with details on the issues it has caused with Quick Look:
http://apple.stackexchange.com/questions/114578/quick-look-s...
See the post at the bottom of the link above. In a nutshell, things like Perian that used to allow Quick Look (not to be confused with the QuickTime Player) to preview a bunch of video formats got hosed when Apple switched over to "AV Foundation" or something.
Considering how many less video formats work with Quick Look after "upgrading" from Snow Leopard to Mavericks, I personally consider it "depreciated" at least in principle.
Quite a lot of Mac users (especially those that work with a lot of video formats) have been waiting for something to fix this Quick Look issue for some years now.
The best you can do at the moment is install this to see thumbnails in Quick Look for some video formats:
https://github.com/Marginal/QLVideo
more info on the issue:
https://github.com/Marginal/QLVideo/issues/3