QuickTime 3 Reference

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Knob Event

The Knob event is used to modify a particular knob or knobs within a specified part.

Figure 12Knob event

Table 8Contents of a Knob event

Knob event type

first nibble value = 1111 (General Event), subtype 7

Length

length of the event will be 2(#knobs+1)

Part

unique part identifier

Knob ID

knob ID within specified part

Knob value

knob value

Event tail

first nibble of last word = 11XX, subtype 7

The part field contains the unique part identifier initially used during the TuneSetHeader call.

The knob number bit field identifies the knob to be changed.

The 32-bit value composed of the lower 16- and upper 16-bit field values is used to alter the specified knob.


© 1997 Apple Computer, Inc.

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