Syntax
js
linearRampToValueAtTime(value, endTime)
Parameters
Return value
A reference to this AudioParam object. In some browsers older
implementations of this interface return undefined.
Examples
In this example, we have a media source with two control buttons (see the audio-param repo for the source code, or view the example live.) When these buttons are pressed, linearRampToValueAtTime() is
used to fade the gain value up to 1.0, and down to 0, respectively. This is pretty
useful for fade in/fade out effects, although AudioParam.exponentialRampToValueAtTime() is often said to be a bit more
natural.
js
// create audio context
const audioCtx = new AudioContext();
// set basic variables for example
const myAudio = document.querySelector("audio");
const linearRampPlus = document.querySelector(".linear-ramp-plus");
const linearRampMinus = document.querySelector(".linear-ramp-minus");
// Create a MediaElementAudioSourceNode
// Feed the HTMLMediaElement into it
const source = audioCtx.createMediaElementSource(myAudio);
// Create a gain node and set its gain value to 0.5
const gainNode = audioCtx.createGain();
// connect the AudioBufferSourceNode to the gainNode
// and the gainNode to the destination
gainNode.gain.setValueAtTime(0, audioCtx.currentTime);
source.connect(gainNode);
gainNode.connect(audioCtx.destination);
// set buttons to do something onclick
linearRampPlus.onclick = () => {
gainNode.gain.linearRampToValueAtTime(1.0, audioCtx.currentTime + 2);
};
linearRampMinus.onclick = () => {
gainNode.gain.linearRampToValueAtTime(0, audioCtx.currentTime + 2);
};
Specifications
| Specification |
|---|
| Web Audio API # dom-audioparam-linearramptovalueattime |