YouTube Music Volume Fix

YTMVolumeFix.user.js

// ==UserScript==
// @name         YouTube Music Volume Fix
// @author       Brett Hagman
// @namespace    https://gist.github.com/bhagman/f3043b28fa6bdf6a630bb192a8bf4a37
// @version      1.0.0
// @description  Changes YTM volume slider to change based on a curve more suited to human hearing.
// @match        https://music.youtube.com/*
// @grant        none
// @run-at       document-end
// ==/UserScript==

// Based on Greasyfork script here:
// https://greasyfork.org/en/scripts/397686-youtube-music-fix-volume-ratio/code
(
  function() {
    'use strict';
    let player = document.querySelector('ytmusic-player-bar');

    if (!player) {
      console.error("Couldn't capture YTM music player.");
      return;
    }
    
    function manipulate () {
      // Capture original function
      const setVolume = player.playerApi_.setVolume;

      // Prepare volume-slider visibility timer
      player.volumeSliderTimeout = -1;

      if (!setVolume) {
        console.log("Player wasn't ready, try again");
        setTimeout(manipulate, 10);
        return;
      }

      // Replace original function
      player.playerApi_.setVolume = function (volume) {
        // console.log('called with volume: ', volume);
        if (volume != player.currentVolume) {
          player.currentVolume = volume;
          // const newVolume = (volume / 100) ** 2 * 100;
          // used two math sites to obtain this curve
          // https://mycurvefit.com/
          // https://www.desmos.com/calculator
          // mycurvefit -- gaussian curve, 0:0, 20:2, 50:16, 80:50, 100:100
          // Finally, subtracted 1 because... reasons. :P (important to get low end closer to 0, than upper end closer to max)
          let newVolume = Math.round(549.5614 * Math.E **(-(((volume-209.232)**2)/(2*59.14962**2))) - 1)
          if (newVolume < 0) newVolume = 0;
          if (newVolume > 100) newVolume = 100;
          // console.log('cV: ', player.currentVolume, ', xV: ', newVolume);
          // Show the volume slider for 5 seconds
          document.querySelector("#volume-slider").classList.add("on-hover");
          if (player.volumeSliderTimeout >= 0) clearTimeout(player.volumeSliderTimeout);
          player.volumeSliderTimeout = setTimeout(() => { document.querySelector("#volume-slider").classList.remove("on-hover");}, 5000);
          // Call original function
          return setVolume.call(this, newVolume);
        }
      };

      // Get initial volume
      if (isNaN(player.currentVolume)) {
        player.currentVolume = -1;
        player.playerApi_.setVolume(player.playerApi_.getVolume());
        // console.log('snagged and set currentVolume: ', player.currentVolume);
      }

      // Shim in our getVolume function
      player.playerApi_.getVolume = function () {
        return player.currentVolume;
      }
    }

    manipulate();
  }
)();