The numberOfChannels
property of the AudioBuffer
interface returns an integer representing the number of discrete audio channels described by the PCM data stored in the buffer.
Syntax
var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate); myArrayBuffer.numberOfChannels;
Value
An integer.
Example
// Stereo var channels = 2; // Create an empty two second stereo buffer at the // sample rate of the AudioContext var frameCount = audioCtx.sampleRate * 2.0; var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate); button.onclick = function() { // Fill the buffer with white noise; // just random values between -1.0 and 1.0 for (var channel = 0; channel < channels; channel++) { // This gives us the actual ArrayBuffer that contains the data var nowBuffering = myArrayBuffer.getChannelData(channel); for (var i = 0; i < frameCount; i++) { // Math.random() is in [0; 1.0] // audio needs to be in [-1.0; 1.0] nowBuffering[i] = Math.random() * 2 - 1; } } console.log(myArrayBuffer.numberOfChannels); }
Specification
Specification | Status | Comment |
---|---|---|
Web Audio API The definition of 'numberOfChannels' 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 | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
numberOfChannels | Chrome Full support 14 | Edge Full support 12 | Firefox Full support 25 | IE No support No | Opera Full support 15 | Safari Full support 6 | WebView Android Full support Yes | Chrome Android Full support 18 | Firefox Android Full support 26 | Opera Android Full support 14 | Safari iOS Full support Yes | Samsung Internet Android Full support 1.0 |
Legend
- Full support
- Full support
- No support
- No support