ref_vfmethod_eventProc - shekh/VirtualDub2 GitHub Wiki

VirtualDub Plugin SDK 1.2

eventProc video filter method

eventProc

Invoked to notify the filter of out of band events during rendering.

bool eventProc(const VDXFilterActivation *fa, const VDXFilterFunctions *ff, uint32 event, void *eventData);

Parameters

fa	Pointer to filter activation structure.
ff	Pointer to callback function structure.
event	ID of event.
eventData	Optional data structure for event. The presence and type of this data is different for each event type.

Thread safety

This method is not thread-safe.

Exceptions

This function must not throw exceptions (see Except()).

Return value

True if the event was recognized and handled, or false otherwise. A host may elect not to send further events of a type if a filter indicates that it does not handle that event type.

API version requirement

Requires V14 or later.

Default behavior

If omitted, no default action is taken.

Remarks

Event IDs use kVDXVFEvent_ as their symbol prefix. The events that can be delivered are as follows:

InvalidateCaches

A change has occurred in an upstream filter that requires caches to be flushed on downstream filters. This generally occurs when upstream filter parameters are tweaked through the UI. Invalidation events are used because they are faster than reinitializing the filter chain.