use it elsewhere

Bit depth buckets

Put it on your own page with two lines, or fork it and make it yours. It is CC-BY-4.0.

Embed

The script finds its own origin, so nothing else is needed; the widget runs in a sandboxed frame and cannot touch your page. Set the controls and the two lines update; the preview beneath shows what your readers get.

<script src="https://learn.mimmsy.com/learn-widget.js"></script> <learn-widget name="bit-depth-buckets"></learn-widget>

It is CC-BY-4.0: keep the credit line the frame shows.

Preview

Fork

A fork is a copy whose manifest names its parent and the parent's version; lineage is kept forever, and the copy is yours to change. The library is its own repository: clone it, copy bit-depth-buckets/ to a new name (one DNS label), set forkedFrom to { "name": "bit-depth-buckets", "version": 1 }, change what you want, run npm run check, and open a pull request. Passing the check is the whole gate. Without a checkout, submit the same files to POST /api/widgets and it is served instantly as an unreviewed draft.

Source

The whole widget is these files; the repository has their history.

widget.json

{
  "name": "bit-depth-buckets",
  "title": "Bit depth buckets",
  "version": 1,
  "claim": "Storing each sample with N bits rounds it to one of 2ᴺ amplitude buckets, so every added bit doubles the buckets, halves the rounding error and raises the SNR by about 6 dB, while pitch and timing are untouched.",
  "summary": "Sweep the bit depth from 1 to 12 while a looping arpeggio plays through a live quantizer: at 12 bits the noise is inaudible, by 4 bits there is a clear hiss, at 1–2 bits the melody is heavily distorted but still in tune. The plot shows the wave snapped to bucket centres and the rounding error left behind; a bypass button removes the quantizer for comparison.",
  "topics": ["audio/digital", "computing/binary"],
  "aliases": ["quantization", "bit depth", "quantization noise", "SNR", "16-bit", "resolution", "levels"],
  "params": {
    "bits": { "type": "integer", "default": 3, "min": 1, "max": 12, "label": "bits per sample" },
    "quantize": { "type": "boolean", "default": true, "label": "quantizer on" }
  },
  "check": [
    {
      "q": "Adding one more bit of depth…",
      "options": ["doubles the buckets and raises the SNR by about 6 dB", "doubles the sample rate", "doubles the highest frequency you can record", "halves the Nyquist limit"],
      "answer": 0,
      "why": "With 2ᴺ buckets each extra bit halves the rounding error and raises the SNR by ≈ 6.02 dB; sample rate and bit depth are independent, rate resolves time and depth resolves amplitude."
    },
    {
      "q": "How many amplitude buckets does 16-bit audio have?",
      "options": ["65,536", "16", "256", "44,100"],
      "answer": 0,
      "why": "A bit depth of 16 gives 2¹⁶ = 65,536 levels; each additional bit doubles the count."
    },
    {
      "q": "Using the ≈ 6 dB per bit rule, 24-bit audio has a theoretical SNR of about…",
      "options": ["146 dB", "98 dB", "24 dB", "6 dB"],
      "answer": 0,
      "why": "6.02 × 24 + 1.76 ≈ 146 dB, more than any playback chain reproduces; the extra range is headroom for recording and mixing."
    },
    {
      "q": "At healthy bit depths, quantization error sounds like…",
      "options": ["a faint noise floor under the signal", "a change in pitch", "a slower tempo", "an echo"],
      "answer": 0,
      "why": "Rounding errors form a quiet, roughly random hiss; pitch and timing are set by the sample clock, not by the buckets."
    }
  ],
  "capabilities": [],
  "height": 470,
  "requires": ["samples-per-cycle"],
  "forkedFrom": null,
  "authors": []
}

index.html

<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Bit depth buckets</title>
<style>
  :root {
    color-scheme: light dark;
    --bg: #f7f3ea;
    --bg-card: #efe9da;
    --border: #d8cfba;
    --text: #211d14;
    --text-dim: #6e6553;
    --accent: #31597f;
    --accent2: #b04e1b;
    --hot: #a82433;
    --ok: #3d6b4f;
    --ink-rgb: 33, 29, 20;
    --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
    --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  }
  @media (prefers-color-scheme: dark) {
    :root {
      --bg: #161410;
      --bg-card: #1e1b15;
      --border: #383225;
      --text: #e9e3d3;
      --text-dim: #9c917c;
      --accent: #8fb8e0;
      --accent2: #dd9355;
      --hot: #df7a88;
      --ok: #82bd97;
      --ink-rgb: 233, 227, 211;
    }
  }

  * { box-sizing: border-box; }
  html, body { margin: 0; }
  body { background: transparent; color: var(--text); font-family: var(--serif); }

  .widget {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 22px;
  }

  .control-row { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; margin-bottom: 14px; }
  .control-row.sym.single {
    display: grid; grid-template-columns: 88px 1fr; gap: 12px 16px;
    align-items: center; margin-bottom: 14px;
  }
  .control-row label { font-size: 14px; color: var(--text-dim); white-space: nowrap; }
  .ctl { display: flex; align-items: center; gap: 10px; min-width: 0; }
  .ctl input[type="range"] { flex: 1; min-width: 0; }
  .ctl .val { flex: none; width: 72px; text-align: right; font-size: 13px; }
  input[type="range"] { accent-color: var(--accent); }
  @media (max-width: 600px) { .control-row.sym.single { grid-template-columns: 64px 1fr; } }

  .toggle { display: inline-flex; align-items: baseline; gap: 7px; font-size: 13.5px; color: var(--text-dim); cursor: pointer; white-space: normal; }
  .toggle input { accent-color: var(--accent2); }

  .mono { font-family: var(--mono); font-variant-numeric: tabular-nums; }
  .dim { color: var(--text-dim); font-size: 12.5px; }

  .chips { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 8px; }
  .btn, .chip {
    font-family: var(--mono); font-size: 12.5px; color: var(--text);
    background: transparent; border: 1px solid var(--border); border-radius: 3px;
    padding: 6px 13px; cursor: pointer; transition: border-color 0.15s, color 0.15s;
  }
  .btn:hover, .chip:hover { border-color: var(--accent); color: var(--accent); }
  .btn.primary { border-color: var(--accent); color: var(--accent); }
  .btn.playing, .btn.playing:hover { border-color: var(--hot); color: var(--hot); }
  .btn.off { border-color: var(--hot); color: var(--hot); opacity: 0.85; }

  .plot { display: block; width: 100%; height: 220px; margin-top: 8px; }
  .plot.tall { height: 280px; }

  .readout-row { display: flex; gap: 28px; flex-wrap: wrap; margin: 14px 0 0; }
  .readout { text-align: left; }
  .readout .big {
    display: block; font-size: 28px; font-weight: 600; color: var(--accent);
    line-height: 1.1; min-width: 5ch; font-variant-numeric: tabular-nums;
  }
  .readout.accent .big { color: var(--accent2); }
  .readout .big.hot { color: var(--hot); }
  .readout small { color: var(--text-dim); font-size: 12.5px; }
  @media (max-width: 560px) {
    .widget { padding: 16px; }
    .readout-row { gap: 12px 18px; }
    .readout .big { font-size: 22px; }
    .plot { height: 180px; }
    .plot.tall { height: 220px; }
    .plot.pipe { height: 200px; }
    .narrow-hide { display: none; }
  }
</style>
</head>
<body>
  <div class="widget" id="root">
    <div class="control-row sym single">
      <label for="bd-n">bit depth</label>
      <span class="ctl wide"><input type="range" id="bd-n" min="1" max="12" value="3"><span class="mono val" id="bd-n-label">3 bits</span></span>
    </div>
    <div class="control-row">
      <button class="btn primary" id="bd-play">&#9654; play melody &middot; loops</button>
      <button class="btn" id="bd-bypass">quantizer: on</button>
    </div>
    <canvas id="bd-canvas" class="plot tall"></canvas>
    <div class="readout-row">
      <div class="readout">
        <span class="big mono" id="bd-levels">8</span>
        <small>buckets &middot; 2&#8319;</small>
      </div>
      <div class="readout">
        <span class="big mono" id="bd-step">0.250</span>
        <small>bucket size &middot; of full range</small>
      </div>
      <div class="readout accent">
        <span class="big mono" id="bd-snr">19.8</span>
        <small>SNR &middot; dB</small>
      </div>
    </div>
  </div>
  <script src="/w/_sdk/host.js?v=1"></script>
  <script src="/w/_lib/audio.js?v=1"></script>
  <script src="widget.js?v=1"></script>
</body>
</html>

widget.js

/* Bit depth buckets: a wave snapped to 2^N levels with its rounding error, and a looping melody quantized live. */
(() => {
  'use strict';
  const K = window.AudioKit;
  const $ = (id) => document.getElementById(id);
  let bits = 3, bypass = false, host = null;
  let shaper = null;

  function render() {
    const levels = Math.pow(2, bits);
    $('bd-n-label').textContent = bits + (bits === 1 ? ' bit' : ' bits');
    $('bd-levels').textContent = K.fmtInt(levels);
    $('bd-step').textContent = (1 / levels).toPrecision(3);
    $('bd-snr').textContent = K.snrDb(bits).toFixed(1);

    const { ctx, w, h } = K.setupCanvas($('bd-canvas'));
    const m = { l: 14, r: 14, t: 14, b: 14 };
    const waveH = (h - m.t - m.b) * 0.62;
    const errH = (h - m.t - m.b) * 0.24;
    const waveMid = m.t + waveH / 2;
    const errMid = m.t + waveH + 18 + errH / 2;
    const sig = (u) => 0.85 * Math.sin(4 * Math.PI * u);
    const Yw = (v) => waveMid - v * (waveH / 2);
    const Ye = (e) => errMid - (e / 0.5) * (errH / 2);

    ctx.clearRect(0, 0, w, h);
    ctx.font = '11px ui-monospace, Menlo, monospace';

    if (levels <= 32) {
      for (let k = 0; k <= levels; k++) K.hline(ctx, m.l, w - m.r, Yw(-1 + k * (2 / levels)), K.T.GRID);
    } else {
      ctx.fillStyle = K.T.DIM;
      ctx.textAlign = 'right';
      ctx.fillText(K.fmtInt(levels) + ' buckets (too fine to draw)', w - m.r, m.t + 10);
    }

    K.trace(ctx, m.l, w - m.r, (u) => Yw(sig(u)), K.T.ACCENT, 1.6, 0.5);
    K.trace(ctx, m.l, w - m.r, (u) => Yw(K.quantize(sig(u), bits)), K.T.ACCENT2, 2.2);

    K.hline(ctx, m.l, w - m.r, errMid, K.T.GRID);
    K.trace(ctx, m.l, w - m.r, (u) => Ye(sig(u) - K.quantize(sig(u), bits)), K.T.HOT, 1.4);
    ctx.fillStyle = K.T.DIM;
    ctx.textAlign = 'left';
    ctx.fillText('quantization error · fixed scale · at most ±½ bucket', m.l + 2, errMid - errH / 2 - 5);
  }

  function curve() {
    const n = 8193;
    const c = new Float32Array(n);
    for (let i = 0; i < n; i++) {
      const x = (i / (n - 1)) * 2 - 1;
      c[i] = bypass ? x : K.quantize(x, bits);
    }
    return c;
  }
  const syncCurve = () => { if (shaper) shaper.curve = curve(); };

  const ping = (data) => { if (host && host.signal) host.signal('interaction', data); };
  function setBits(n) {
    bits = K.clamp(Math.round(n), 1, 12);
    $('bd-n').value = bits;
    render();
    syncCurve();
  }
  function setBypass(off) {
    bypass = off;
    const btn = $('bd-bypass');
    btn.classList.toggle('off', bypass);
    btn.textContent = bypass ? 'quantizer: off' : 'quantizer: on';
    syncCurve();
  }

  $('bd-n').addEventListener('input', () => { setBits(+$('bd-n').value); ping({ bits }); });
  $('bd-bypass').addEventListener('click', () => { setBypass(!bypass); ping({ bypass }); });

  K.bindPlay($('bd-play'), (ctx) => {
    const { data } = K.getMelody(ctx.sampleRate);
    const loop = K.loopBuffer(ctx, data, 0.5);
    shaper = ctx.createWaveShaper();
    syncCurve();
    loop.connect(shaper);
    return () => { shaper = null; loop.stop(); };
  }, () => ping({ play: 'melody', bits }));
  K.stopWhenHidden($('root'));

  K.debounceResize(render);
  render();

  LearnWidget.connect().then((h) => {
    host = h;
    K.fitFrame(h, $('root'));
    const apply = (p) => {
      if (typeof p.bits === 'number') setBits(p.bits);
      if (typeof p.quantize === 'boolean') setBypass(!p.quantize);
    };
    apply(h.params || {});
    h.on('theme.changed', () => { K.readTheme(); render(); });
    h.on('params.changed', apply);
    K.readTheme();
    render();
  });
})();