Twitch - AudioCompressor

Adds a toggle to the Twitch player that compresses volume dynamics. This is a port of the audio compressor feature from https://github.com/crackededed/Xtra.

Terá de instalar uma extensão como Tampermonkey, Greasemonkey ou Violentmonkey para instalar este script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

Terá de instalar uma extensão como Tampermonkey ou Violentmonkey para instalar este script.

Terá de instalar uma extensão como Tampermonkey ou Userscripts para instalar este script.

Terá de instalar uma extensão como Tampermonkey para instalar este script.

Terá de instalar uma extensão de gestão de scripts de utilizador para instalar este script.

(Já tenho um gestor de scripts de utilizador, deixe-me instalá-lo!)

Terá de instalar uma extensão como Stylus para instalar este estilo.

Terá de instalar uma extensão como Stylus para instalar este estilo.

Terá de instalar uma extensão como Stylus para instalar este estilo.

Terá de instalar uma extensão de gestão de estilos de utilizador para instalar este estilo.

Terá de instalar uma extensão de gestão de estilos de utilizador para instalar este estilo.

Terá de instalar uma extensão de gestão de estilos de utilizador para instalar este estilo.

(Já tenho um gestor de estilos de utilizador, deixe-me instalá-lo!)

// ==UserScript==
// @name        Twitch - AudioCompressor
// @namespace   https://ioj4.net
// @version     1.0.1
// @match       https://twitch.tv/*
// @match       https://*.twitch.tv/*
// @grant       none
// @license     AGPL-3.0
// @author      ioj4
// @description Adds a toggle to the Twitch player that compresses volume dynamics. This is a port of the audio compressor feature from https://github.com/crackededed/Xtra.
// ==/UserScript==

const UNIQUE_KEY="twitch-audio-compressor-injection";

const lazyQueries = new Set();
const observer = new MutationObserver(() => {
  lazyQueries.forEach(e => {
    const result = e.query();
    if (!result) return;
    if (e.once) lazyQueries.delete(e);
    e.callback(result);
  })
});
observer.observe(document.body, { subtree: true, attributes: true });

const lazySelector = (query, callback, once) => {
  const result = query();
  if (result) {
    callback(result);
    if (once) return;
  }
  const e = { query, callback, once };
  lazyQueries.add(e);
  return () => lazyQueries.delete(e);
}


class RemovedListener extends HTMLElement {
  onRemoved;
  connectedCallback() {
    this.style.display = "contents";
  }
  disconnectedCallback() {
    this.onRemoved?.();
  }
}

customElements.define("removed-listener", RemovedListener);

// https://github.com/crackededed/Xtra/blob/377bfac17ff67f49f58593f79f17850693277aa0/app/src/main/res/drawable-xxhdpi/baseline_audio_compressor_off_24dp.png
const inactiveIcon = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADAAAAAwCAYAAABXAvmHAAAAAXNSR0IB2cksfwAAAARnQU1BAACxjwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAAZiS0dEAP8A/wD/oL2nkwAAAAlwSFlzAAALEwAACxMBAJqcGAAAAAd0SU1FB+oEHgIeIaXh78cAAACdSURBVGje7ZdLDoAgDESBcP/r6sKkXsAofwZ8b9UFaTp2WsQ5AABZzMyU4icCbQKRWfnyas35rWfgvwJa2oAOKA76NAGjNxIWmj3oQamgkvz7W0hl3y/XgdQPxxZCQCVRtTDvvW8iIDURFhphod7dKMkf1QrCQqrbZrqAXnaKK/q+iQCV+4F/IYD3V9GRGZ+Z56+c80XPOqUYAECPG/S35yssDd9BAAAAAElFTkSuQmCC";
// https://github.com/crackededed/Xtra/blob/377bfac17ff67f49f58593f79f17850693277aa0/app/src/main/res/drawable-xxhdpi/baseline_audio_compressor_on_24dp.png
const activeIcon = "data:image/png;base64,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";
const style = document.createElement("style");
style.innerText = `
.twitch-audio-compressor-toggle {
  display: flex;
  border-radius: 50%;

  input {
    appearance: none;
    cursor: pointer;
    width: var(--button-size-default, 3.2rem);
    height: var(--button-size-default, 3.2rem);
    background: url("${inactiveIcon}") center/75% no-repeat;
  }
  input:checked {
    background: url("${activeIcon}") center/75% no-repeat;
  }
}

.twitch-audio-compressor-toggle:hover {
  background-color: var(--color-background-button-text-hover, rgba(255, 255, 255, 0.13));
}
`;
document.documentElement.append(style);

function addCompressor(s) {
  // Initialization and Source
  const audioContext = new (window.AudioContext || window.webkitAudioContext)();
  const source = audioContext.createMediaElementSource(s.video);

  // Hijack the player volume and apply it after the processing chain
  const userGain = audioContext.createGain();
  userGain.gain.value = s.video.volume;
  s.video.volume = 1;

  Object.defineProperty(s.video, "volume", {
    set(v) {
      userGain.gain.setValueAtTime(v, audioContext.currentTime);
      s.video.dispatchEvent(new Event("volumechange"));
      return v;
    },
    get() {
     return userGain.gain.value;
    }
  });

  // Dry
  const dryGain = audioContext.createGain();
  dryGain.gain.value = s.enabledInitially ? 0 : 1;
  source.connect(dryGain);
  dryGain.connect(userGain);

  // Wet
  const compressor = audioContext.createDynamicsCompressor();
  // Parameters taken from:
  // https://github.com/crackededed/Xtra/blob/377bfac17ff67f49f58593f79f17850693277aa0/app/src/main/java/com/github/andreyasadchy/xtra/ui/player/PlaybackService.kt#L583
  compressor.threshold.value = -50;
  compressor.knee.value = 40;
  compressor.ratio.value = 12;
  compressor.attack.value = 0;
  compressor.release.value = 0.25;
  source.connect(compressor);

  const wetGain = audioContext.createGain();
  wetGain.gain.value = s.enabledInitially ? 1 : 0;
  compressor.connect(wetGain);

  wetGain.connect(userGain);

  // Destination
  userGain.connect(audioContext.destination);

  // Account for restrictive autoplay rules
  const resumeIfNotRunning = () => {
    if (audioContext.state !== "running") audioContext.resume();
  }

  document.addEventListener("mousedown", resumeIfNotRunning);
  document.addEventListener("touchstart", resumeIfNotRunning);

  s.update = (enabled) => {
    dryGain.gain.linearRampToValueAtTime(enabled ? 0 : 1, audioContext.currentTime + 0.5);
    wetGain.gain.linearRampToValueAtTime(enabled ? 1 : 0, audioContext.currentTime + 0.5);
  }
}

function addToggle(s) {
  // Reinsert toggle when needed
  const removedListener = document.createElement("removed-listener");
  removedListener.onRemoved = () => lazySelector(
    () => s.player.querySelector(".player-controls__left-control-group"),
    (newLeftControls) => addToggle({ ...s, leftControls: newLeftControls}),
    true
  );

  const wrapper = document.createElement("div");
  const toggle = document.createElement("input");
  toggle.type = "checkbox";
  toggle.checked = s.enabledInitially;
  wrapper.classList.add("twitch-audio-compressor-toggle");
  wrapper.appendChild(toggle);
  removedListener.appendChild(wrapper);

  const pauseButton = s.leftControls.firstElementChild;
  pauseButton.insertAdjacentElement("afterend", removedListener);

  toggle.addEventListener("change", (e) => {
    const enabled = e.target.checked;
    localStorage.setItem(`${UNIQUE_KEY}-enabled-initially`, enabled ? "1" : "0");
    s.update?.(enabled); // Toggle between dry and wet
  });
}

function patchPlayer(s) {
  try {
    s.leftControls = s.player.querySelector(".player-controls__left-control-group");
    s.video = s.player.querySelector("video");
    addCompressor(s);
    addToggle(s);
  } catch (e) {
    console.warn(`[Twitch-Audio-Compressor] ${e}`);
  }
}

lazySelector(
  () => document.querySelectorAll(`div.video-player:has(.player-controls__left-control-group, video):not([${UNIQUE_KEY}])`),
  (players) => {
    const enabledInitially = localStorage.getItem(`${UNIQUE_KEY}-enabled-initially`) === "1";
    players.forEach(player => {
      player.setAttribute(UNIQUE_KEY, "");
      const s = { player, enabledInitially };
      patchPlayer(s);
    });
  },
  false
);