☰

Boost Volume

Boost video volume on any site. Shortcuts: Alt-Shift-[+/-]

  1. // ==UserScript==
  2. // @name         Boost Volume
  3. // @namespace    http://greasyfork.org/
  4. // @version      0.3
  5. // @description  Boost video volume on any site. Shortcuts: Alt-Shift-[+/-]
  6. // @author       rix
  7. // @match        *://*/*
  8. // @grant        none
  9. // ==/UserScript==
  10.  
  11. (() => {
  12.     const boostVolume = (() => {
  13.         const sources = {};
  14.         const context = new AudioContext();
  15.         return (gain) => {
  16.             for (let video of document.querySelectorAll('video')) {
  17.                 try {
  18.                     const source = context.createMediaElementSource(video);
  19.                     const gainNode = context.createGain(source);
  20.                     source.connect(gainNode);
  21.                     gainNode.connect(context.destination);
  22.                     sources[video] = gainNode;
  23.                 } catch(e) {}
  24.             }
  25.             for (let [video, gainNode] of Object.entries(sources)) {
  26.                 try {
  27.                     gainNode.gain.value = gain;
  28.                 } catch(e) {}
  29.             }
  30.         };
  31.     })();
  32.     let gain = 1;
  33.     document.body.addEventListener('keyup', e => {
  34.         if (!(e instanceof KeyboardEvent && e.type === 'keyup')) return;
  35.         if (e.composed && e.altKey && !e.ctrlKey && !e.metaKey && e.shiftKey) {
  36.             if (e.keyCode === 187) { // +
  37.                 gain++;
  38.             }
  39.             else if (e.keyCode === 189) { // -
  40.                 gain = Math.max(gain - 1, 1);
  41.             }
  42.             else return;
  43.             boostVolume(gain);
  44.         }
  45.     });
  46. })();