ScriptProcessorNode: audioprocess event
Deprecated
Avoid using this feature in new projects. This feature may be a candidate for removal from web standards or browsers.
The audioprocess event of the ScriptProcessorNode interface is fired when an input buffer of a script processor is ready to be processed.
Note:
This feature was replaced by AudioWorklets and the AudioWorkletNode interface.
This event is not cancelable and does not bubble.
Syntax
Use the event name in methods like addEventListener(), or set an event handler property.
js
addEventListener("audioprocess", (event) => { })
onaudioprocess = (event) => { }
Event type
An AudioProcessingEvent. Inherits from Event.
Examples
js
scriptNode.addEventListener("audioprocess", (audioProcessingEvent) => {
// The input buffer is a song we loaded earlier
const inputBuffer = audioProcessingEvent.inputBuffer;
// The output buffer contains the samples that will be modified and played
const outputBuffer = audioProcessingEvent.outputBuffer;
// Loop through the output channels (in this case there is only one)
for (let channel = 0; channel < outputBuffer.numberOfChannels; channel++) {
const inputData = inputBuffer.getChannelData(channel);
const outputData = outputBuffer.getChannelData(channel);
// Loop through the 4096 samples
for (let sample = 0; sample < inputBuffer.length; sample++) {
// make output equal to the same as the input
outputData[sample] = inputData[sample];
// add noise to each output sample
outputData[sample] += (Math.random() * 2 - 1) * 0.2;
}
}
});
You could also set up the event handler using the onaudioprocess property:
js
scriptNode.onaudioprocess = (audioProcessingEvent) => {
// …
};
Specifications
| Specification |
|---|
| Web Audio API # eventdef-scriptprocessornode-audioprocess |