The read-only audioLevel property of the RTCRtpContributingSource interface indicates the audio level contained in the last RTP packet played from the described source. audioLevel will be the level value defined in [RFC6465] if the RFC 6465 header extension is present, and otherwise null.
Syntax
var audioLevel = RTCRtpContributingSource.audioLevel
Value
A double-precision floating-point number which indicates the volume level of the audio in the most recently received RTP packet from the source described by the RTCRtpContributingSource.
This value, which is in the range 0.0 to 1.0, is on a linear scale and its value is defined in dBov, or decibels (overload). This is the amplitude relative to the point at which clipping of the audio begins to occur. A value of 1.0 represents 0 dBov (maximum volume), a value of 0.0 represents silence, and a value of 0.5 represents approximately 6 dB SPL (decibels of sound pressure level) change in the sound pressure level from 0 dBov.
For both RTCRtpContributingSource and RTCRtpSynchronizationSource, the audio level is converted to this form from the values defined in the specifications corresponding to each type of source.
audioLevel may be absent from RTCRtpContributingSource objects, which indicates that no volume level was provided by the source; however, it is required and always available on all RTCRtpSynchronizationSource objects.
Specifications
| Specification | Status | Comment |
|---|---|---|
| WebRTC 1.0: Real-time Communication Between Browsers The definition of 'audioLevel' in that specification. |
Candidate Recommendation | Initial definition. |
Browser compatibility
| Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | No | ? | 591 | No | No | ? |
| Feature | Android webview | Chrome for Android | Edge mobile | Firefox for Android | Opera Android | iOS Safari | Samsung Internet |
|---|---|---|---|---|---|---|---|
| Basic support | No | No | ? | 591 | No | ? | No |
1. From version 59: this feature is behind the media.peerconnection.rtpsourcesapi.enable preference (needs to be set to true). To change preferences in Firefox, visit about:config.