Sets a media's playback rate. This effective rate accounts for any master time bases that may be in use with the current movie.
Positive values represent forward rates and negative values indicate reverse rates.
Returns noErr if there is no error. Your media handler can use this function to determine when your media is playing, and the direction and rate of playback. This information can help you prepare for playback more efficiently. Click the link to send email to the QuickTime documentation team. This will open an email window with the filename of this page as the subject.