Inside Macintosh: QuickTime /

Chapter 2 - Movie Toolbox / Movie Toolbox Reference

Functions That Modify Movie Properties / Working With Alternate Tracks

GetTrackAlternate

The GetTrackAlternate function allows your application to determine all the tracks in an alternate group. You specify the group by identifying a track in the group. The group list is circular, so you must specify a different track in the group each time you call this function.

pascal Track GetTrackAlternate (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 GetTrackAlternate function returns the track identifier of the next track in the group. If the track you specify does not belong to a group, the function returns the same identifier you supply. Because the alternate group list is circular, you have retrieved all the tracks in the group when the function returns the track identifier that you supplied the first time you called the GetTrackAlternate function. If there is only one track in an alternate group, this function returns the track identifier you supply.

ERROR CODES

invalidTrack

-2009

This track is corrupted or invalid

SEE ALSO

You can add a track to a group by calling the SetTrackAlternate function, which is described in the previous section.