Youtube Highest Quality

Automatically selects the best available video quality on YouTube.

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         Youtube Highest Quality
// @author       tzshuhag
// @namespace    http://tampermonkey.net/
// @version      1.0
// @match        *://www.youtube.com/*
// @match        *://m.youtube.com/*
// @match        *://www.youtube-nocookie.com/*
// @exclude      *://www.youtube.com/live_chat*
// @homepageURL  https://tzshuhag.me
// @icon         https://raw.githubusercontent.com/tz-shuhag/YT-HD/refs/heads/main/128.png
// @grant        none
// @run-at       document-idle
// @license      MIT
// @description  Automatically selects the best available video quality on YouTube.
// ==/UserScript==
 
/* jshint esversion: 11 */
 
(async function () {
    'use strict';
 
    const QUALITIES = {
        highres: 4320,
        hd2160: 2160,
        hd1440: 1440,
        hd1080: 1080,
        hd720: 720,
        large: 480,
        medium: 360,
        small: 240,
        tiny: 144
    };
 
    const PREMIUM_INDICATOR_LABEL = "Premium";
 
    // Global variables
    let moviePlayer = null;
    let isIframe = false;
 
    async function setResolution() {
        if (!moviePlayer) {
            console.log('Movie player not found.');
            return;
        }
 
        // Debounce to prevent rapid calls
        let debounceTimer;
        if (debounceTimer) clearTimeout(debounceTimer);
        debounceTimer = setTimeout(async () => {
            try {
                const videoQualityData = moviePlayer.getAvailableQualityData();
                if (!videoQualityData.length) {
                    console.log('No quality data available, waiting for playback...');
                    const videoElement = moviePlayer.querySelector('video');
                    if (videoElement && videoElement.paused) {
                        videoElement.addEventListener('play', setResolution, { once: true });
                    }
                    return;
                }
 
                const availableQualities = moviePlayer.getAvailableQualityLevels();
                const highestQuality = availableQualities.reduce((max, q) => 
                    QUALITIES[q] > QUALITIES[max] ? q : max, availableQualities[0]);
                const premiumData = videoQualityData.find(q =>
                    q.quality === highestQuality &&
                    q.qualityLabel?.trim().endsWith(PREMIUM_INDICATOR_LABEL) &&
                    q.isPlayable
                );
 
                moviePlayer.setPlaybackQualityRange(highestQuality, highestQuality, premiumData?.formatId);
                console.log(`Set quality to: [${highestQuality}${premiumData ? ' Premium' : ''}]`);
            } catch (error) {
                console.error('Failed to set resolution:', error);
            }
        }, 100);
    }
 
    function processVideoLoad(event = null) {
        console.log('Processing video load...');
        moviePlayer = event?.target?.player_ ?? document.querySelector('#movie_player');
        if (moviePlayer) setResolution();
    }
 
    function addEventListeners() {
        if (window.location.hostname === 'm.youtube.com') {
            window.addEventListener('state-navigateend', processVideoLoad, true);
        } else {
            window.addEventListener('yt-player-updated', processVideoLoad, true);
        }
    }
 
    async function initialize() {
        if (window.self !== window.top) isIframe = true;
        window.addEventListener('pageshow', processVideoLoad, true);
        addEventListeners();
    }
 
    function hasGreasyMonkeyAPI() {
        return typeof GM !== 'undefined' || typeof GM_info !== 'undefined';
    }
 
    if (hasGreasyMonkeyAPI()) {
        initialize();
    } else {
        console.error('No Grease Monkey API detected.');
    }
})();