The createChannelMerger()
method of the BaseAudioContext
interface creates a ChannelMergerNode
, which combines channels from multiple audio streams into a single audio stream.
Syntax
baseAudioContext.createChannelMerger(numberOfInputs);
Parameters
- numberOfInputs
- The number of channels in the input audio streams, which the output stream will contain; the default is 6 if this parameter is not specified.
Returns
Example
The following example shows how you could separate a stereo track (say, a piece of music), and process the left and right channel differently. To use them, you need to use the second and third parameters of the AudioNode.connect(AudioNode)
method, which allow you to specify both the index of the channel to connect from and the index of the channel to connect to.
var ac = new AudioContext(); ac.decodeAudioData(someStereoBuffer, function(data) { var source = ac.createBufferSource(); source.buffer = data; var splitter = ac.createChannelSplitter(2); source.connect(splitter); var merger = ac.createChannelMerger(2); // Reduce the volume of the left channel only var gainNode = ac.createGain(); gainNode.gain.setValueAtTime(0.5, ac.currentTime); splitter.connect(gainNode, 0); // Connect the splitter back to the second input of the merger: we // effectively swap the channels, here, reversing the stereo image. gainNode.connect(merger, 0, 1); splitter.connect(merger, 1, 0); var dest = ac.createMediaStreamDestination(); // Because we have used a ChannelMergerNode, we now have a stereo // MediaStream we can use to pipe the Web Audio graph to WebRTC, // MediaRecorder, etc. merger.connect(dest); });
Specifications
Specification | Status | Comment |
---|---|---|
Web Audio API The definition of 'createChannelMerger()' in that specification. |
Working Draft |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
createChannelMerger | Chrome
Full support
10
| Edge Full support ≤18 | Firefox
Full support
53
| IE No support No | Opera
Full support
22
| Safari
Full support
6
| WebView Android Full support Yes | Chrome Android Full support 33 | Firefox Android
Full support
53
| Opera Android
Full support
22
| Safari iOS
Full support
6
| Samsung Internet Android Full support 2.0 |
Legend
- Full support
- Full support
- No support
- No support
- See implementation notes.
- See implementation notes.
- Requires a vendor prefix or different name for use.
- Requires a vendor prefix or different name for use.