SPEVENT

SPEVENT contains information about an event. Events are passed from the TTS or SR engines or audio devices back to applications.

typedef struct SPEVENT
{
    WORD         eEventId;
    WORD         elParamType;
    ULONG        ulStreamNum;
    ULONGLONG    ullAudioStreamOffset;
    WPARAM       wParam;
    LPARAM       lParam;
} SPEVENT;

Members

eEventId

The event ID of type SPEVENTENUM. 

elParamType

The signature of the associated data in the lParam parameter
The user may need to release associated data after using the event. See SPEVENTLPARAMTYPE for more information about associated data.

ulStreamNum

The stream number associated with the event.
For text-to-speech (i.e., output streams), the stream number is incremented each time a new speak call (e.g. ISpVoice::SpeakStream, ISpVoice::Speak) is made.
For speech recognition (i.e., input streams), the stream is incremented each time an audio stream is opened (i.e., ISpSREngine::RecognizeStream). Note that a single audio input object can be opened multiple times (e.g., buffer overflow, device error, recognition state change).

ullAudioStreamOffset

The byte offset into the audio stream associated with the event at which the event was fired. For synthesis, the output stream is the synthesized data. For recognition, this indicates the position in the input audio stream.

wParam

The generic word field. For event IDs with the SPFEI_LPARAM_IS_POINTER set, this is the size, in bytes, for the data pointed to by lParam. In some cases, the type of event will change the function of this parameter. See SPEVENTENUM for information about specific events.
See the helper SpClearEvent for more information about releasing objects or memory attached to an event.

lParam

The generic event field. For event IDs with the SPFEI_LPARAM_IS_POINTER set, this points to the data allocated by CoTaskMemAlloc. The caller is responsible for freeing this memory using CoTaskMemFree(). In some cases, the type of event will change the function of this parameter. See SPEVENTENUM for information about specific events.
See the helper SpClearEvent for more information about releasing objects or memory attached to an event.