VidAmplifier

VidAmplifier is a user script designed to enhance the audio of videos on YouTube beyond their default maximum volume.

K instalaci tototo skriptu si budete muset nainstalovat rozšíření jako Tampermonkey, Greasemonkey nebo Violentmonkey.

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

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Userscripts.

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

K instalaci tohoto skriptu si budete muset nainstalovat manažer uživatelských skriptů.

(Už mám manažer uživatelských skriptů, nechte mě ho nainstalovat!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(Už mám manažer uživatelských stylů, nechte mě ho nainstalovat!)

// ==UserScript==
// @name         VidAmplifier
// @namespace    https://github.com/DemianAdam/VidAmplifier
// @version      0.3
// @description  VidAmplifier is a user script designed to enhance the audio of videos on YouTube beyond their default maximum volume.
// @author       Dnam
// @match        https://www.youtube.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=youtube.com
// @license      GPL-3.0-only
// ==/UserScript==

(function () {
    'use strict';
    let audioCtx;
    let source;
    let gainNode;

    let elementsReady = setInterval(()=>{
        if (!source) {
            let video = document.querySelector('video');
            audioCtx = new AudioContext();
            source = audioCtx.createMediaElementSource(video);
            gainNode = audioCtx.createGain();
            source.connect(gainNode);
            gainNode.connect(audioCtx.destination);
            clearInterval(elementsReady);
            elementsReady = true;
            console.log("elements");

        }
    },1000)
    /*document.addEventListener('yt-navigate-start', () => mainVolumeGain(gainNode));
    mainVolumeGain(gainNode);*/
    let ready = setInterval(()=> {
        if(elementsReady){
            mainVolumeGain(gainNode,ready);
            console.log("source");
        }
    },1000);
})();

function mainVolumeGain(gainNode,ready) {
    if(document.querySelector("#videoVolumeSpan") || location.url == "https://www.youtube.com")
    {
        return;
    }
    let gain = gainNode.gain.value;
    addVolumeSpan();
    addVolumeShorcutEvents();
    initializeGainChangedEvent();
    function volumeUp() {
        gainNode.gain.value += 0.25;
    }
    function volumeDown() {
        gainNode.gain.value -= 0.25;
    }
    function resetVolume() {
        gainNode.gain.value = 1;
    }
    function volumeChange(e) {
        let changed = false;
        if (e.altKey && e.code === "NumpadAdd") {
            volumeUp();
            changed = true;
        }
        else if (e.altKey && e.code === "NumpadSubtract") {
            if (gainNode.gain.value > 1) {
                volumeDown();
            }
            changed = true;
        }
        else if (e.altKey && e.code === "NumpadDivide") {
            resetVolume();
            changed = true;
        }
        if (changed) {
            document.getElementById('movie_player').wakeUpControls();
        }
    }
    function addVolumeShorcutEvents() {
        document.addEventListener('keyup', volumeChange);
    }

    function createSpan() {
        let control = document.createElement("span");
        control.setAttribute("id", "videoVolumeSpan");
        control.innerHTML = "Volume: x" + gainNode.gain.value;
        control.style.border = "0.5px solid"
        control.style.padding = "0.5em";
        return control;
    }

    function createContainer(control) {
        let container = document.createElement("div");
        container.style.marginLeft = "2px";
        container.append(control);
        return container;
    }
    function addVolumeSpan() {
        if (!document.querySelector("#videoVolumeSpan")) {
            let volumeArea = document.querySelector(".ytp-volume-area");
            let control = createSpan();
            let container = createContainer(control);
            volumeArea.parentNode.insertBefore(container, volumeArea.nextSibling);
        }
    }
    function updateGainSpan() {
        let control = document.querySelector("#videoVolumeSpan");
        control.innerHTML = "Volume: x" + gainNode.gain.value;
    }
    function gainChangedEvent(functsOnGainChanges) {
        if (gain != gainNode.gain.value) {
            functsOnGainChanges.forEach(element => {
                element();
            });
            gain = gainNode.gain.value;
        }
    }
    function initializeGainChangedEvent() {
        const OnGainChanged = [];
        OnGainChanged.push(updateGainSpan);
        setInterval(() => gainChangedEvent(OnGainChanged), 250);
    }
    clearInterval(ready);
}