The ScriptProcessorNode interface allows the generation, processing, or analyzing of audio using JavaScript.

The ScriptProcessorNode interface is an AudioNode audio-processing module that is linked to two buffers, one containing the input audio data, one containing the processed output audio data. An event, implementing the AudioProcessingEvent interface, is sent to the object each time the input buffer contains new data, and the event handler terminates when it has filled the output buffer with data.

The size of the input and output buffer are defined at the creation time, when the BaseAudioContext.createScriptProcessor method is called (both are defined by BaseAudioContext.createScriptProcessor's bufferSize parameter). The buffer size must be a power of 2 between 256 and 16384, that is 256, 512, 1024, 2048, 4096, 8192 or 16384. Small numbers lower the latency, but large number may be necessary to avoid audio breakup and glitches.

If the buffer size is not defined, which is recommended, the browser will pick one that its heuristic deems appropriate.

Instance properties

Inherits properties from its parent, AudioNode.

ScriptProcessorNode.bufferSize Read only

Returns an integer representing both the input and output buffer size. Its value can be a power of 2 value in the range 256 – 16384.

Instance methods

No specific methods; inherits methods from its parent, AudioNode.

Events

Listen to these events using addEventListener() or by assigning an event listener to the oneventname property of this interface:

audioprocess

Fired when an input buffer of a ScriptProcessorNode is ready to be processed. Also available via the onaudioprocess event handler property.

Examples

See BaseAudioContext.createScriptProcessor() for example code.

Specifications

Browser compatibility

See also

• Using the Web Audio API