diff --git a/index.bs b/index.bs index 2b8a7db00..aa05e1451 100644 --- a/index.bs +++ b/index.bs @@ -12171,7 +12171,7 @@ class Bitcrusher extends AudioWorkletProcessor { // No need to return a value; this node's lifetime is dependent only on its // input connections. } -}); +}; registerProcessor('bitcrusher', Bitcrusher); diff --git a/index.html b/index.html index 2a0615b9c..126d1b867 100644 --- a/index.html +++ b/index.html @@ -8,7 +8,7 @@ - + @@ -1065,7 +1065,7 @@

Web Audio API

-

Editor’s Draft,

+

Editor’s Draft,

More details about this document
@@ -12354,7 +12354,7 @@
AudioParams (in this case, treated as a-rate) inside an AudioWorkletProcessor.

const context = new AudioContext();context.audioWorklet.addModule('bitcrusher.js').then(() => {    const osc = new OscillatorNode(context);    const amp = new GainNode(context);    // Create a worklet node. 'BitCrusher' identifies the    // AudioWorkletProcessor previously registered when    // bitcrusher.js was imported. The options automatically    // initialize the correspondingly named AudioParams.    const bitcrusher = new AudioWorkletNode(context, 'bitcrusher', {        parameterData: {bitDepth: 8}    });    osc.connect(bitcrusher).connect(amp).connect(context.destination);    osc.start();});
-
class Bitcrusher extends AudioWorkletProcessor {    static get parameterDescriptors () {        return [{            name: 'bitDepth',            defaultValue: 12,            minValue: 1,            maxValue: 16        }, {            name: 'frequencyReduction',            defaultValue: 0.5,            minValue: 0,            maxValue: 1        }];    }    constructor (options) {        // The initial parameter value can be set by passing |options|        // to the processor’s constructor.        super(options);        this._phase = 0;        this._lastSampleValue = 0;    }    process (inputs, outputs, parameters) {        const input = inputs[0];        const output = outputs[0];        const bitDepth = parameters.bitDepth;        const frequencyReduction = parameters.frequencyReduction;        if (bitDepth.length > 1) {            for (let channel = 0; channel < output.length; ++channel) {                for (let i = 0; i < output[channel].length; ++i) {                    let step = Math.pow(0.5, bitDepth[i]);                    // Use modulo for indexing to handle the case where                    // the length of the frequencyReduction array is 1.                    this._phase += frequencyReduction[i % frequencyReduction.length];                    if (this._phase >= 1.0) {                        this._phase -= 1.0;                        this._lastSampleValue =                            step * Math.floor(input[channel][i] / step + 0.5);                    }                    output[channel][i] = this._lastSampleValue;                }            }        } else {            // Because we know bitDepth is constant for this call,            // we can lift the computation of step outside the loop,            // saving many operations.            const step = Math.pow(0.5, bitDepth[0]);            for (let channel = 0; channel < output.length; ++channel) {                for (let i = 0; i < output[channel].length; ++i) {                    this._phase += frequencyReduction[i % frequencyReduction.length];                    if (this._phase >= 1.0) {                        this._phase -= 1.0;                        this._lastSampleValue =                            step * Math.floor(input[channel][i] / step + 0.5);                    }                    output[channel][i] = this._lastSampleValue;                }            }        }        // No need to return a value; this node’s lifetime is dependent only on its        // input connections.    }});registerProcessor('bitcrusher', Bitcrusher);
+
class Bitcrusher extends AudioWorkletProcessor {    static get parameterDescriptors () {        return [{            name: 'bitDepth',            defaultValue: 12,            minValue: 1,            maxValue: 16        }, {            name: 'frequencyReduction',            defaultValue: 0.5,            minValue: 0,            maxValue: 1        }];    }    constructor (options) {        // The initial parameter value can be set by passing |options|        // to the processor’s constructor.        super(options);        this._phase = 0;        this._lastSampleValue = 0;    }    process (inputs, outputs, parameters) {        const input = inputs[0];        const output = outputs[0];        const bitDepth = parameters.bitDepth;        const frequencyReduction = parameters.frequencyReduction;        if (bitDepth.length > 1) {            for (let channel = 0; channel < output.length; ++channel) {                for (let i = 0; i < output[channel].length; ++i) {                    let step = Math.pow(0.5, bitDepth[i]);                    // Use modulo for indexing to handle the case where                    // the length of the frequencyReduction array is 1.                    this._phase += frequencyReduction[i % frequencyReduction.length];                    if (this._phase >= 1.0) {                        this._phase -= 1.0;                        this._lastSampleValue =                            step * Math.floor(input[channel][i] / step + 0.5);                    }                    output[channel][i] = this._lastSampleValue;                }            }        } else {            // Because we know bitDepth is constant for this call,            // we can lift the computation of step outside the loop,            // saving many operations.            const step = Math.pow(0.5, bitDepth[0]);            for (let channel = 0; channel < output.length; ++channel) {                for (let i = 0; i < output[channel].length; ++i) {                    this._phase += frequencyReduction[i % frequencyReduction.length];                    if (this._phase >= 1.0) {                        this._phase -= 1.0;                        this._lastSampleValue =                            step * Math.floor(input[channel][i] / step + 0.5);                    }                    output[channel][i] = this._lastSampleValue;                }            }        }        // No need to return a value; this node’s lifetime is dependent only on its        // input connections.    }};registerProcessor('bitcrusher', Bitcrusher);

Note: In the definition of AudioWorkletProcessor class, an InvalidStateError will be thrown if the author-supplied constructor has an explicit return value that is not this or does not properly call super().

1.32.7.2. VU Meter Node