Third-party developers can create components, or plug-ins, for the use in the open architecture of QuickTime. These third-party components expand the functionality of QuickTime, allowing QuickTime to play additional media types.
If you are using an Intel-based Mac, be sure to visit the component developer's website to download a Universal binary component that is compatible with Intel-based Macintosh computers. PowerPC-based QuickTime components will not work natively in QuickTime on an Intel-based Mac.
Please see the QuickTime third-party component page for a list of QuickTime components with links to their respective manufacturers.
If the required component is not available from the third party in a Universal version that will run on an Intel-based Mac, you can work around the issue by forcing QuickTime Player to run under Rosetta. Components that were developed for PowerPC-based Macs will be able to run while QuickTime is running under Rosetta. See "Intel-based Macs: Forcing a Universal application to run with Rosetta" for steps.
In addition to third-party components, there is also a QuickTime component that's made by Apple: the QuickTime MPEG-2 Playback Component. Apple has created a Universal version of this component for users of Intel-based Macs. If you purchased the PowerPC version of the MPEG-2 Playback Component from the Apple Store online, you are eligible to receive the Universal version for free. Follow the directions below to receive the updated MPEG-2 Playback Component.