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IDtmfRecognizer Interface

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This content is no longer actively maintained. It is provided as is, for anyone who may still be using these technologies, with no warranties or claims of accuracy with regard to the most recent product version or service release.

Creates a DtmfRecognizer object for processing telephone keypad (DTMF) input.

Namespace: Microsoft.SpeechServer.Recognition
Assembly: Microsoft.SpeechServer (in microsoft.speechserver.dll)

Syntax

'Declaration
Public Interface IDtmfRecognizer

public interface IDtmfRecognizer

Remarks

The IDtmfRecognizer interface is primarily intended to create the DtmfRecognizer object on an application???s TelephonySession. All examples of IDtmfRecognizer functionality in this document use the TelephonySessionDtmfRecognizer object.

Only one DTMF recognition can be active at the same time. If one or more DTMF grammars are loaded, key presses are recognized against these grammars; otherwise, no recognition takes place and the DtmfRecognizer returns the detected digits until explicitly stopped.

In automatic mode, the DtmfRecognizer automatically stops on a timeout, or on completion of a recognition (successful or failed). In continuous mode, the DtmfRecognizer stops only when RecognizeAsync is invoked or when an error occurs.

The RecognizeStarted event is raised when recognition starts, and the RecognizeCompleted event is raised whenever recognition stops. The RecognizeCompletedEventArgs contains the recognition result (if any) and the reason that recognition stopped.

Recognition cannot start until all outstanding grammar loads have completed. If any grammar loads fail to complete within a certain time, recognition is aborted, but the remaining grammar loads are allowed to continue. If any grammar loads fail, the error is returned in the LoadGrammarCompletedEventArgs and aborts recognition.

Platforms

Development Platforms

Windows XP Professional with Service Pack 2 (SP2), Windows Server 2003, Windows Vista Ultimate Edition, Windows Vista Business Edition, Windows Vista Enterprise Edition

Target Platforms

Windows Server 2003

See Also

Reference

IDtmfRecognizer Members
Microsoft.SpeechServer.Recognition Namespace