Inside Macintosh: QuickTime /

Chapter 2 - Movie Toolbox / Movie Toolbox Reference

Functions That Modify Movie Properties / Working With Sound Volume

GetTrackVolume

The GetTrackVolume function returns a track's current volume setting.

pascal short GetTrackVolume (Track theTrack);

theTrack

Specifies the track for this operation. Your application obtains this track identifier from such Movie Toolbox functions as NewMovieTrack and GetMovieTrack (described on page 2-136 and page 2-188, respectively).

DESCRIPTION

The GetTrackVolume function returns an integer that contains the track's current volume represented as a 16-bit, fixed-point number. 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 -1.0 to 1.0. Negative values play no sound but preserve the absolute value of the volume setting.

ERROR CODES

invalidTrack

-2009

This track is corrupted or invalid

SEE ALSO

You can change a track's current volume by calling the SetTrackVolume function, which is described in the previous section.