The RTCDTMFSender
interface provides a mechanism for transmitting DTMF codes on a WebRTC RTCPeerConnection
. You gain access to the connection's RTCDTMFSender
through the RTCRtpSender.dtmf
property on the audio track you wish to send DTMF with.
The primary purpose for WebRTC's DTMF support is to allow WebRTC-based communication clients to be connected to a public-switched telephone network (PSTN) or other legacy telephone service, including extant voice over IP (VoIP) services. For that reason, DTMF can't be used between two WebRTC-based devices, because there is no mechanism provided by WebRTC for receiving DTMF codes.
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Properties
RTCDTMFSender.toneBuffer
Read only- A
DOMString
which contains the list of DTMF tones currently in the queue to be transmitted (tones which have already been played are no longer included in the string). SeetoneBuffer
for details on the format of the tone buffer.
Methods
RTCDTMFSender.insertDTMF()
- Given a string describing a set of DTMF codes and, optionally, the duration of and inter-tone gap between the tones,
insertDTMF()
starts sending the specified tones. CallinginsertDTMF()
replaces any already-pending tones from thetoneBuffer
. You can abort sending queued tones by specifying an empty string (""
) as the set of tones to play.
Events
Listen to these events using addEventListener()
or by assigning an event listener to the oneventname
property of this interface.
tonechange
- The
tonechange
event is sent to theRTCDTMFSender
instance's event handler to indicate that a tone has either started or stopped playing.
Also available using theontonechange
event handler property.
Example
See the article Using DTMF with WebRTC for a full example.
Specifications
Specification | Status | Comment |
---|---|---|
WebRTC 1.0: Real-time Communication Between Browsers The definition of 'RTCDTMFSender' in that specification. |
Candidate Recommendation |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
RTCDTMFSender | Chrome Full support 27 | Edge Full support ≤79 | Firefox Full support 52 | IE No support No | Opera Full support Yes | Safari ? | WebView Android Full support 4.4 | Chrome Android Full support 27 | Firefox Android Full support 52 | Opera Android Full support Yes | Safari iOS ? | Samsung Internet Android Full support 1.5 |
canInsertDTMF | Chrome Full support 27 | Edge Full support ≤79 | Firefox ? | IE No support No | Opera Full support Yes | Safari ? | WebView Android Full support Yes | Chrome Android Full support 27 | Firefox Android ? | Opera Android Full support Yes | Safari iOS ? | Samsung Internet Android Full support 1.5 |
insertDTMF | Chrome Full support 27 | Edge Full support ≤79 | Firefox Full support 52 | IE No support No | Opera Full support Yes | Safari ? | WebView Android Full support 4.4 | Chrome Android Full support 27 | Firefox Android Full support 52 | Opera Android Full support Yes | Safari iOS ? | Samsung Internet Android Full support 1.5 |
ontonechange | Chrome Full support 27 | Edge Full support ≤79 | Firefox Full support 52 | IE No support No | Opera Full support Yes | Safari ? | WebView Android Full support Yes | Chrome Android Full support 27 | Firefox Android Full support 52 | Opera Android Full support Yes | Safari iOS ? | Samsung Internet Android Full support 1.5 |
toneBuffer | Chrome Full support 27 | Edge Full support ≤79 | Firefox Full support 52 | IE No support No | Opera Full support Yes | Safari ? | WebView Android Full support 4.4 | Chrome Android Full support 27 | Firefox Android Full support 52 | Opera Android Full support Yes | Safari iOS ? | Samsung Internet Android Full support 1.5 |
tonechange event | Chrome Full support 27 | Edge Full support ≤79 | Firefox Full support 52 | IE No support No | Opera Full support Yes | Safari ? | WebView Android Full support Yes | Chrome Android Full support 27 | Firefox Android Full support 52 | Opera Android Full support Yes | Safari iOS ? | Samsung Internet Android Full support 1.5 |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown