QuickTime 4 Reference

Getting a List of Effects

Before your application presents the standard parameters dialog box to users, you will probably want to build a list of the effects that are available. QuickTime provides the QTGetEffectsList function to do this for you. This returns a QTAtomContainer that contains a list of all the effects currently available.

Important
This function can take several seconds to execute, so you should typically call it only once when your application is launched (or after a pair of suspend and resume events).

You can remove effects from the returned list if you want to restrict the set of effects the user can choose from.

If you present the standard parameters dialog box without providing a list of effects, the dialog function gets the list of available effects automatically. This can save you a few lines of code, but your users must wait while QuickTime searches for available effects and generates the list every time you open the dialog box.