Interface ScriptProcessorNode

This interface is an AudioNode which can generate, process, or analyse audio directly using JavaScript.

numberOfInputs  : 1
numberOfOutputs : 1

The ScriptProcessorNode is constructed with a bufferSize which must be one of the following values: 256, 512, 1024, 2048, 4096, 8192, 16384. This value controls how frequently the onaudioprocess event handler is called and how many sample-frames need to be processed each call. Lower numbers for bufferSize will result in a lower (better) latency. Higher numbers will be necessary to avoid audio breakup and glitches. The value chosen must carefully balance between latency and audio quality.

numberOfInputChannels and numberOfOutputChannels determine the number of input and output channels. It is invalid for both numberOfInputChannels and numberOfOutputChannels to be zero.

var node = context.createScriptProcessor(bufferSize, numberOfInputChannels, numberOfOutputChannels);

Hierarchy

Index

Properties

Methods

Properties

public bufferSize: number

The size of the buffer (in sample-frames) which needs to be processed each time onprocessaudio is called. Legal values are (256, 512, 1024, 2048, 4096, 8192, 16384).

public context: AudioContext

The AudioContext which owns this AudioNode.

public numberOfInputs: number

The number of inputs feeding into the AudioNode. This will be 0 for an AudioSourceNode.

public numberOfOutputs: number

The number of outputs coming out of the AudioNode. This will be 0 for an AudioDestinationNode.

public onaudioprocess: EventListener

An event listener which is called periodically for audio processing. An event of type AudioProcessingEvent will be passed to the event handler.

Methods

public connect(destination: AudioNode, output?: number, input?: number)

Connects the AudioNode to another AudioNode.

It is possible to connect an AudioNode output to more than one input with multiple calls to connect(). Thus, "fanout" is supported.

It is possible to connect an AudioNode to another AudioNode which creates a cycle. In other words, an AudioNode may connect to another AudioNode, which in turn connects back to the first AudioNode. This is allowed only if there is at least one DelayNode in the cycle or an exception will be thrown.

There can only be one connection between a given output of one specific node and a given input of another specific node. Multiple connections with the same termini are ignored. For example:

nodeA.connect(nodeB);
nodeA.connect(nodeB);

will have the same effect as

nodeA.connect(nodeB);

Parameters

  • destination: AudioNode

    the AudioNode to connect to.

  • output?: number optional

    an index describing which output of the AudioNode from which to connect. An out-of-bound value throws an exception.

  • input?: number optional

    an index describing which input of the destination AudioNode to connect to. An out-of-bound value throws an exception.

public connect(destination: AudioParam, output?: number)

Connects the AudioNode to an AudioParam, controlling the parameter value with an audio-rate signal.

It is possible to connect an AudioNode output to more than one AudioParam with multiple calls to connect(). Thus, "fanout" is supported.

It is possible to connect more than one AudioNode output to a single AudioParam with multiple calls to connect(). Thus, "fanin" is supported.

An AudioParam will take the rendered audio data from any AudioNode output connected to it and convert it to mono by down-mixing if it is not already mono, then mix it together with other such outputs and finally will mix with the intrinsic parameter value (the value the AudioParam would normally have without any audio connections), including any timeline changes scheduled for the parameter.

There can only be one connection between a given output of one specific node and a specific AudioParam. Multiple connections with the same termini are ignored. For example:

nodeA.connect(param);
nodeA.connect(param);

will have the same effect as

nodeA.connect(param);

Parameters

  • destination: AudioParam

    the AudioParam to connect to.

  • output?: number optional

    an index describing which output of the AudioNode from which to connect. An out-of-bound value throws an exception.

public disconnect(output?: number)

Disconnects an AudioNode's output.

Parameters

  • output?: number optional

    an index describing which output of the AudioNode to disconnect. An out-of-bound value throws an exception.