QuickTime 3 Reference
The QuickTime music architecture is implemented as Component Manager components, which is the standard mechanism that QuickTime uses to provide extensibility.
QTMA components exist both in QuickTime for Macintosh and QuickTime for Windows. Note that in QuickTime 3 for Windows, MIDI is not yet supported; only the QuickTime Music Synthesizer is available.
Different QTMA components are used by a QuickTime movie, depending on if you are playing music or sounds through the computer's built-in speaker, or if you are controlling, for example, a MIDI synthesizer. During playback of a QuickTime movie, the music media handler component isolates your application and the Movie Toolbox from the details of how to actually play a music track. The task of processing the data in a music track is taken care of for you by the media handler through Movie Toolbox calls.
The following sections provide overviews of these components and their capabilities.