QuickTime 3 Reference
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An effect description tells QuickTime which effect to execute and contains the parameters that control how the effect behaves at runtime. You create an effect description by creating an atom container, inserting a QT Atom that specifies the effect, and inserting a set of QT Atoms that set its parameters.
There are support functions you can call to assist you in this process. QTCreateStandardParameterDialog will return a complete effect description that you can use, including user-selected settings (you will need to add kEffectSourceName atoms for effects that require one or two sources). At a lower level, QTGetEffectsList will return a list of the available effects and ImageCodecGetParameterList will return a description of the parameters for an effect, including the default value for each parameter in the form of a QT Atom that can be inserted directly into an effect description.
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