AudioWorkletNode: AudioWorkletNode() constructor
The AudioWorkletNode()
constructor creates a new AudioWorkletNode
object, which represents an
AudioNode
that uses a JavaScript function to perform custom audio
processing.
Syntax
js
new AudioWorkletNode(context, name)
new AudioWorkletNode(context, name, options)
Parameters
context
-
The
BaseAudioContext
instance this node will be associated with. name
-
A string, which represents the name of the
AudioWorkletProcessor
this node will be based on. A processor with the provided name must first be registered using theAudioWorkletGlobalScope.registerProcessor()
method. options
Optional-
An object containing zero or more of the following optional properties to configure the new node:
Note: The result of the structured clone algorithm applied to the object is also internally passed into the associated
AudioWorkletProcessor()
constructor — this allows custom initialization of an underlying user-definedAudioWorkletProcessor
.numberOfInputs
Optional-
The value to initialize the
numberOfInputs
property to. Defaults to 1. numberOfOutputs
Optional-
The value to initialize the
numberOfOutputs
property to. Defaults to 1. outputChannelCount
Optional-
An array defining the number of channels for each output. For example, outputChannelCount: [n, m] specifies the number of channels in the first output to be n and the second output to be m. The array length must match
numberOfOutputs
. parameterData
Optional-
An object containing the initial values of custom
AudioParam
objects on this node (in itsparameters
property), withkey
being the name of a custom parameter andvalue
being its initial value. processorOptions
Optional-
Any additional data that can be used for custom initialization of the underlying
AudioWorkletProcessor
.
Exceptions
NotSupportedError
DOMException
-
The specified
options.outputChannelCount
is0
or larger than the current implementation supports.Both
options.numberOfInputs
andoptions.numberOfOutputs
are 0. IndexSizeError
DOMException
-
The length of
options.outputChannelCount
array does not matchoptions.numberOfOutputs
.
Usage notes
Different options
parameter values can have the following effects.
If the number of inputs and number of outputs are both set to 0, a NotSupportedError
will be thrown and the node construction process aborted. If the length of the outputChannelCount
array doesn't match numberOfOutputs
, an IndexSizeError
DOMException
will be thrown.
If outputChannelCount
isn't specified, and numberOfInputs
and numberOfOutputs
are both 1, the AudioWorkletNode
's initial channel count is set to 1. This has the effect of changing the output channel count to dynamically change to the computed number of channels, based on the input's channel count and the current setting of the AudioNode
property channelCountMode
.
Otherwise, if outputChannelCount
is provided and if the values of numberOfInputs
and numberOfOutputs
are both 1, the audio worklet node's channel count is set to the value of outputChannelCount
. Otherwise, the channel count of each channel in the set of output channels is set to match the corresponding value in the outputChannelCount
array.
Examples
For a complete example demonstrating user-defined audio processing, see the
AudioWorkletNode
page.
Specifications
Specification |
---|
Web Audio API # dom-audioworkletnode-audioworkletnode |
Browser compatibility
BCD tables only load in the browser