AudioBuffer: numberOfChannels property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

ThenumberOfChannels property of theAudioBufferinterface returns an integer representing the number of discrete audio channelsdescribed by the PCM data stored in the buffer.

Value

An integer.

Examples

// Stereoconst channels = 2;// Create an empty two second stereo buffer at the// sample rate of the AudioContextconst frameCount = audioCtx.sampleRate * 2.0;const myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);button.onclick = () => {  // Fill the buffer with white noise;  // just random values between -1.0 and 1.0  for (let channel = 0; channel < channels; channel++) {    // This gives us the actual ArrayBuffer that contains the data    const nowBuffering = myArrayBuffer.getChannelData(channel);    for (let 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);};