AudioWorkletGlobalScope: registerProcessor() method

{{ APIRef("Web Audio API") }}

The registerProcessor method of the {{domxref("AudioWorkletGlobalScope")}} interface registers a class constructor derived from {{domxref("AudioWorkletProcessor")}} interface under a specified name.

Syntax

registerProcessor(name, processorCtor)

Parameters

• name
  • : A string representing the name under which the processor will be registered.
• processorCtor
  • : The constructor of a class derived from {{domxref("AudioWorkletProcessor")}}.

[!NOTE] A key-value pair { name: constructor } is saved internally in the {{domxref("AudioWorkletGlobalScope")}} once the processor is registered. The name is to be referred to when creating an {{domxref("AudioWorkletNode")}} based on the registered processor. A new processor by the given name is internally created and associated with the new node.

Return value

None ({{jsxref("undefined")}}).

Exceptions

• NotSupportedError {{domxref("DOMException")}}

  • : Thrown under the following conditions:
    • The name is an empty string.
    • A constructor under the given name is already registered. Registering the same name twice is not allowed.

• {{jsxref("TypeError")}}

  • : Thrown under the following conditions:
    • The processorCtor is not a callable constructor.
    • The {{domxref("AudioWorkletProcessor.parameterDescriptors", "parameterDescriptors")}} property of the constructor exists and doesn't return an array of {{domxref("AudioParamDescriptor")}}-based objects.

Examples

In this example we create a custom AudioWorkletNode that outputs silence.

First, we need to define a custom {{domxref("AudioWorkletProcessor")}} and register it. Note that this should be done in a separate file.

// test-processor.js
class TestProcessor extends AudioWorkletProcessor {
  process(inputs, outputs, parameters) {
    return true;
  }
}

registerProcessor("test-processor", TestProcessor);

Next, in our main script file we'll load the processor, create an instance of AudioWorkletNode — passing it the processor name that we used when calling registerProcessor — and connect it to an audio graph.

const audioContext = new AudioContext();
await audioContext.audioWorklet.addModule("test-processor.js");
const node = new AudioWorkletNode(audioContext, "test-processor");
node.connect(audioContext.destination);

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• Using the Web Audio API