Jan 1, 2011
Alternatives to QuickTime on OS X
If you’ve recently switched to OS X from Windows, or if you use both platforms regularly, you will notice that a lot of the video you played with ease on Windows does not play on OS X. Apple includes QuickTime as the default video viewer on OS X, but it cannot handle a wide variety of video codecs, so you will inevitably need to find an additional video player

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Alternatives to QuickTime on OS X