Notify listeners of event. NOTIFY(H,'EVENTNAME') notifies listeners added to the event named EVENTNAME on handle object array H that the event is taking place.
H is the array of handles to objects triggering the event, and EVENTNAME must be a string.

NOTIFY(H,'EVENTNAME',DATA) provides a way of encapsulating information about an event which can then be accessed by each registered listener. DATA must belong to the EVENT.EVENTDATA class.

Help for cv.DescriptorExtractor/notify is inherited from superclass handle