Microsoft Speech Platform


Applications can receive notifications when words have been spoken during speech synthesis or when words have been recognized during speech recognition. Speech Platform components that generate notifications implement an ISpNotifySource.

The ISpNotifySource and ISpNotifySink interfaces alone only provide a mechanism for a notification but no information on the events that caused the notification. With an ISpEventSource object, an application can retrieve information about the events that caused the notification.

Applications will not typically use the free-threaded ISpNotifySink mechanism for receiving Speech Platform event notifications. They will use one of the simplified methods of either a window message, callback or Win32 event.

Note that both variations of callbacks as well as the window message notification require a window message pump to run on the thread that initialized the notification source. Callback will only be called as the result of window message processing, and will always be called on the same thread that initialized the notify source. However, using Win32 events for Speech Platform event notification does not require a window message pump.

Implemented By

Methods in Vtable Order

ISpNotifySource Methods Description
SetNotifySink Sets up the instance to make free-threaded calls through ISpNotifySink::Notify.  This method can also be used to unregister an existing notification.
SetNotifyWindowMessage Sets a window handle to receive notifications as window messages.
SetNotifyCallbackFunction Sets a callback function to receive notifications.
SetNotifyCallbackInterface Sets an object to receive notifications.
SetNotifyWin32Event Sets up a Win32 event object to be used by this instance for notifications.
WaitForNotifyEvent A blocking call which waits for a notification.
GetNotifyEventHandle Retrieves Win32 event handle associated with this notify source.