Inside Macintosh: QuickTime /

Chapter 2 - Movie Toolbox / Movie Toolbox Reference

Functions for Getting and Playing Movies / Preferred Movie Settings

GetMoviePreferredVolume

The GetMoviePreferredVolume function returns a movie's preferred volume setting.

pascal short GetMoviePreferredVolume (Movie theMovie);

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).

DESCRIPTION

The GetMoviePreferredVolume function returns a 16-bit, fixed-point number that contains the movie's default volume. The high-order 8 bits contain the integer part of the value; the low-order 8 bits contain the fractional part. Volume values range from 0.0 to 1.0.

You can change a movie's current volume by calling the SetMovieVolume function, which is described on page 2-167.

A movie's tracks have their own volume settings. Use the SetTrackVolume function, described on page 2-168, to set the volume of an individual track. A track's volume is scaled by the movie's volume to produce the track's final volume. Furthermore, the movie's volume is scaled by the sound volume that is returned by the Operating System's GetSoundVol routine (described in Inside Macintosh: More Macintosh Toolbox). Thus, the user can control the overall volume from the Sound control panel.

ERROR CODES

invalidMovie

-2010

This movie is corrupted or invalid

SEE ALSO

When a movie is loaded, the current setting is set to preferred volume. The StartMovie function (described on page 2-98) uses this volume setting when it starts playing a movie.