Audio gain processor using the Web Audio API. Provides volume control for audio streams before they are sent to WebRTC.

Methods

# inner GainProcessor(options) → {GainProcessorResult}

Creates an audio gain processor for volume control.

This function creates a Web Audio processing chain that allows real-time volume adjustment of an audio stream. The processed stream can be used with WebRTC while maintaining volume control.

Parameters:

Name	Type	Attributes	Default	Description
`options`	`Object`			Configuration options
`audioContext`	`AudioContext`			The Web Audio AudioContext
`stream`	`MediaStream`			The input audio stream to process
`gainValue`	`number`	<optional>	1	Initial gain value (0 = muted, 1 = normal, >1 = amplified)

Returns:

Object containing gainNode, inputNode, and producerTrack

Type: GainProcessorResult

Example

// Create audio context and get microphone stream
const audioContext = new AudioContext();
const stream = await navigator.mediaDevices.getUserMedia({ audio: true });

// Create gain processor
const { gainNode, producerTrack } = GainProcessor({
  audioContext,
  stream,
  gainValue: 0.8 // Start at 80% volume
});

// Use producerTrack for WebRTC
const producer = await sendTransport.produce({ track: producerTrack });

// Adjust volume dynamically
gainNode.gain.value = 0.5; // Set to 50% volume
gainNode.gain.value = 0;   // Mute
gainNode.gain.value = 1.5; // Amplify to 150%

Type Definitions

Type: Object

# GainProcessorResult

Result object returned by GainProcessor

Properties:

Name	Type	Description
`gainNode`	`GainNode`	The Web Audio GainNode for adjusting volume (use gainNode.gain.value)
`inputNode`	`MediaStreamAudioSourceNode`	The source node connected to the gain
`producerTrack`	`MediaStreamTrack`	The processed audio track to use for WebRTC production