WebAudio/audio_werklet_example.html at main · J-W-C/WebAudio · GitHub

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<!DOCTYPE html>
<html>

  <head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
    <meta name="viewport" content="width=device-width">
    <title>AudioWorklet example</title>
  </head>

  <body>
    <h1>AudioWorklet example</h1>
    <button>Make Telephone Sound</button>
    <pre></pre>
  </body>

  <script>

    // Display this script in page's preformatted secion
    const myScript = document.querySelector('script');
    const pre = document.querySelector('pre');
    pre.innerHTML = myScript.innerHTML;

    let Player_node;

    const audioContext = new AudioContext({latencyHint: "interactive", sampleRate: 16000});

    audioContext.audioWorklet.addModule('audio_werklet_proc.js').then(() => {
        Player_node = new AudioWorkletNode(audioContext, 'pcm_player');
        Player_node.connect(audioContext.destination)
        setTimeout(()=>audioContext.close(), 30000);
    });

    const button = document.querySelector('button');
    button.onclick = function() {

        console.log('XXX - Sending test waveform to Worklet');

        const sample_hz = 16000;
        const td_480 = sample_hz / 480.0 / Math.PI / 2.0;
        const td_620 = sample_hz / 620.0 / Math.PI / 2.0;

        // Build the test waveform
        const samples = 1 * sample_hz;
        let wave = new Int16Array(samples);
        for (let s = 0; s < samples; s++) {
            let sample = (Math.sin(s / td_480) + Math.sin(s / td_620)) / 2.0;
            wave[s] = Math.trunc(0x3fff * sample);
        }

        // Send it in (20ms) chunks to the Worklet processor
        for (let n = 0; n < wave.length / 320;  n++) {
            let array = wave.slice(n * 320, (n + 1) * 320);
            Player_node.port.postMessage(array);
        }
    }

  </script>

</html>