AudioContext: getOutputTimestamp() method - Web APIs | MDN

Syntax

Parameters

None.

Return value

An AudioTimestamp object, which has the following properties.

  • contextTime: A point in the time coordinate system of the currentTime for the BaseAudioContext; the time after the audio context was first created.
  • performanceTime: A point in the time coordinate system of a Performance interface; the time after the document containing the audio context was first rendered

Examples

In the following code we start to play an audio file after a play button is clicked, and start off a requestAnimationFrame loop running, which constantly outputs the contextTime and performanceTime.

You can see full code of this example at output-timestamp (see it live also).

js

// Press the play button
playBtn.addEventListener("click", () => {
  // We can create the audioCtx as there has been some user action
  audioCtx ??= new AudioContext();
  source = new AudioBufferSourceNode(audioCtx);
  getData();
  source.start(0);
  playBtn.disabled = true;
  stopBtn.disabled = false;
  rAF = requestAnimationFrame(outputTimestamps);
});

// Press the stop button
stopBtn.addEventListener("click", () => {
  source.stop(0);
  playBtn.disabled = false;
  stopBtn.disabled = true;
  cancelAnimationFrame(rAF);
});

// Helper function to output timestamps
function outputTimestamps() {
  const ts = audioCtx.getOutputTimestamp();
  output.textContent = `Context time: ${ts.contextTime} | Performance time: ${ts.performanceTime}`;
  rAF = requestAnimationFrame(outputTimestamps); // Reregister itself
}

Specifications

Specification
Web Audio API
# dom-audiocontext-getoutputtimestamp

Browser compatibility

Help improve MDN

Learn how to contribute

This page was last modified on by MDN contributors.