The PlaybackReceivedRFC2833Dtmf API procedure controls whether incoming RFC2833 DTMF is played back on local multimedia hardware. Normally, in-band DTMF audio information in the call's media channel is not present when using RFC2833 DTMF. If your application needs to "hear" received DTMF from the far end of the call (such as a soft phone), you will want to enable local playback of received RFC2833 DTMF signals.

Namespace:  LanScape
Assembly:  LMEVoipManaged (in LMEVoipManaged.dll) Version: 6.0.5226.26700


public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE PlaybackReceivedRFC2833Dtmf(
	int PhoneLine,
	bool DtmfPlaybackEnableState
Visual Basic (Declaration)
Public Function PlaybackReceivedRFC2833Dtmf ( _
	PhoneLine As Integer, _
	DtmfPlaybackEnableState As Boolean _
Visual C++
VoipMediaEngine..::.TELEPHONY_RETURN_VALUE PlaybackReceivedRFC2833Dtmf(
	int PhoneLine, 
	bool DtmfPlaybackEnableState
public VoipMediaEngine..::.TELEPHONY_RETURN_VALUE PlaybackReceivedRFC2833Dtmf(
	int PhoneLine,
	boolean DtmfPlaybackEnableState


Type: System..::.Int32
The zero based phone line to access.
Type: System..::.Boolean
The state of received RFC2833 DTMF playback.

Return Value

If the function succeeds, the return value will be SipSuccess.

If the function fails, the return value will be one of the following values as specified by the VoipMediaEngine..::.TELEPHONY_RETURN_VALUE data type.

Return ValueDescription
This value is returned by telephony API procedures to indicate general API failure. This error value is used as a "catch all error". If you receive this error, check to make sure that all parameters specified in the API procedure call are correct. Particularly, verify that pointers to memory regions are valid. This error return value is only used if a mapping to another specific error value does not exist.

(API return value)

Application software specified an invalid telephony handle in one of the API procedures. This usually indicates memory corruption on the part of application software.

(API return value)

Application software called a telephony API procedure and specified an invalid phone line. Phone lines are numbered starting from zero. This error is most commonly returned when attempting to access phone lines in excess of the max number of lines supported by the telephony engine.

(API return value)

The application tried to destroy an RFC2833 DTMF decoder for a phone line using the UnInitializeRfc2833DtmfDecoder(Int32) API procedure and the DTMF decoder did not exists.

(API return value)

Internal media engine in-band and RFC2833 DTMF support has not been enabled. See the DtmfEnabled startup parameter in the VoipMediaEngine..::.START_SIP_TELEPHONY_PARAMS structure for additional information.

(API return value)



See Also