77 lines
2.2 KiB
TypeScript
77 lines
2.2 KiB
TypeScript
import * as Message from "./message"
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import Renderer from "./renderer"
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import Decoder from "./decoder"
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import { RingInit } from "./ring"
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// Abstracts the Worker and Worklet into a simpler API
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// This class must be created on the main thread due to AudioContext.
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export default class Audio {
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context: AudioContext;
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worker: Worker;
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worklet: Promise<AudioWorkletNode>;
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constructor() {
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// Assume 44.1kHz and two audio channels
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const config = {
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sampleRate: 44100,
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ring: new RingInit(2, 4410), // 100ms at 44.1khz
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}
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this.context = new AudioContext({
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latencyHint: "interactive",
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sampleRate: config.sampleRate,
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})
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this.worker = this.setupWorker(config)
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this.worklet = this.setupWorklet(config)
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}
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private setupWorker(config: Message.Config): Worker {
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const url = new URL('worker.ts', import.meta.url)
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const worker = new Worker(url, {
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name: "audio",
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type: "module",
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})
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worker.postMessage({ config })
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return worker
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}
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private async setupWorklet(config: Message.Config): Promise<AudioWorkletNode> {
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// Load the worklet source code.
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const url = new URL('worklet.ts', import.meta.url)
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await this.context.audioWorklet.addModule(url)
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const volume = this.context.createGain()
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volume.gain.value = 2.0;
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// Create a worklet
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const worklet = new AudioWorkletNode(this.context, 'renderer');
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worklet.onprocessorerror = (e: Event) => {
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console.error("Audio worklet error:", e)
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};
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worklet.port.postMessage({ config })
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// Connect the worklet to the volume node and then to the speakers
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worklet.connect(volume)
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volume.connect(this.context.destination)
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return worklet
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}
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init(init: Message.Init) {
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this.worker.postMessage({ init })
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}
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segment(segment: Message.Segment) {
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this.worker.postMessage({ segment }, [ segment.buffer.buffer, segment.reader ])
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}
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play(play: Message.Play) {
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this.context.resume()
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//this.worker.postMessage({ play })
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}
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} |