Inside Macintosh: QuickTime /

Chapter 2 - Movie Toolbox / Movie Toolbox Reference

Functions for Getting and Playing Movies / Enhancing Movie Playback Performance

PrerollMovie

The PrerollMovie function allows your application to prepare a portion of a movie for playback.

pascal OSErr PrerollMovie (Movie theMovie, TimeValue time, 
                           Fixed Rate);

theMovie

Specifies the movie for this operation. Your application obtains this movie identifier from such functions as NewMovie, NewMovieFromFile, and NewMovieFromHandle (described on page 2-80, page 2-76, and page 2-78, respectively).

time

Contains the starting time of the movie segment to play.

Rate

Specifies the rate at which you anticipate playing the movie. You specify the movie rate as a 32-bit, fixed-point number. Positive integers indicate forward rates and negative integers indicate reverse rates.

DESCRIPTION

When your application calls the PrerollMovie function, the Movie Toolbox tells the appropriate media handlers to prepare to play the movie. The media handlers may then load the movie data and perform any other necessary preparations to play the movie, such as allocating sound channels and starting up image-decompression sequences. In this manner, you can eliminate playback stutter when the movie starts playing.

ERROR CODES

invalidMovie	-2010	This movie is corrupted or invalid
invalidTime	-2015	This time value is invalid