On-demand Youtube embedded player

Hugely improves load speed of pages with lots of embedded Youtube videos by instantly showing clickable and immediately accessible placeholders, then the thumbnails are loaded in background.

目前為 2015-04-27 提交的版本,檢視 最新版本

您需要先安裝使用者腳本管理器擴展,如 TampermonkeyGreasemonkeyViolentmonkey 之後才能安裝該腳本。

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

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyViolentmonkey 後才能安裝該腳本。

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyUserscripts 後才能安裝該腳本。

你需要先安裝一款使用者腳本管理器擴展,比如 Tampermonkey,才能安裝此腳本

您需要先安裝使用者腳本管理器擴充功能後才能安裝該腳本。

(我已經安裝了使用者腳本管理器,讓我安裝!)

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

(我已經安裝了使用者樣式管理器,讓我安裝!)

// ==UserScript==
// @name          On-demand Youtube embedded player
// @description   Hugely improves load speed of pages with lots of embedded Youtube videos by instantly showing clickable and immediately accessible placeholders, then the thumbnails are loaded in background.
// @version       1.0.6
// @author        wOxxOm
// @namespace     wOxxOm.scripts
// @license       MIT License
// @grant         GM_addStyle
// @grant         GM_xmlhttpRequest
// @run-at        document-start
// ==/UserScript==

var resizeToFit = true;
var embedSelector = 'iframe[src*="youtube.com/embed"], embed[src*="youtube.com/v"]';

GM_addStyle('\
    .instant-youtube-container:not(small) {position:relative; overflow:hidden; cursor:pointer; background-color:black}\
    .instant-youtube-container:not(small) .instant-youtube-thumbnail {transition:opacity 0.1s ease-out; opacity:0}\
    .instant-youtube-container:not(small) .instant-youtube-play-button {position:absolute; left:0; right:0; top:0; bottom:0; margin:auto; width:85px; height:60px}\
    .instant-youtube-container:not(small) .instant-youtube-loading-button {position:absolute; left:0; right:0; top:0; bottom:0; margin:auto; display:block; width:20px; height:20px; background: url("data:image/gif;base64,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")}\
    .instant-youtube-container:hover:not(small) .ytp-large-play-button-svg {fill:#CC181E}\
    .instant-youtube-container:not(small) .instant-youtube-link {\
      position:absolute; top:50%; left:0; right:0; width:20em; height:1.7em; margin:60px auto;\
      display:block; text-align:center; text-decoration:none; color:white; text-shadow:1px 1px 3px black;\
    }\
    .instant-youtube-container:not(small) .instant-youtube-link:hover { color:white; text-decoration:underline; background:transparent }\
    .instant-youtube-container:not(small) .instant-youtube-embed {position:absolute; left:0; top:0}\
    .instant-youtube-container:not(small) .instant-youtube-link2 {\
      display:none; z-index:9; background-color:rgba(0,0,0,0.5); color: white;\
      width:100%; height: 1.7em; top:0; left:0; right:0; position:absolute; z-index: 9;\
      font-size:11pt; color:white; text-shadow:1px 1px 2px black; text-align:center; text-decoration:none;\
      margin:0; padding:0.5em 0.5em 0.2em;\
    }\
    .instant-youtube-container:not(small):hover .instant-youtube-link2 {display:block}\
    .instant-youtube-container:not(small) .instant-youtube-link2:hover {text-decoration:underline}\
');

processNodes(null, document.querySelectorAll(embedSelector));
setMutationHandler(document, embedSelector, processNodes);

function processNodes(observer, nodes) {
  for (var i=0, nl=nodes.length, n; i<nl && (n=nodes[i]); i++) {
    if (!n.parentNode || n.className.indexOf('instant-youtube-') >= 0 || n.src.indexOf('autoplay=1') > 0)
      continue;

    var id = n.src.match(/(?:embed\/|v[=\/])(.+?)(?:[&?\/].*|$)/);
    if (!id)
      continue;
    id = id[1];

    for (var np=n.parentNode, npw; np && !(npw=np.clientWidth); np=np.parentNode) {}
    var containerWidth = resizeToFit ? npw : n.clientWidth;
    var containerHeight = resizeToFit ? npw / 16 * 9 : n.clientHeight;

    var div = document.createElement('div');
    div.className = 'instant-youtube-container';
    div.srcEmbed = n.src;
    div.style.maxWidth = containerWidth + 'px';
    div.style.height = containerHeight + 'px';

    var img = div.appendChild(document.createElement('img'));
    img.className = 'instant-youtube-thumbnail';
    img.src = 'https://i.ytimg.com/vi' + (window.chrome?'_webp':'') + '/' + id + '/maxresdefault.' + (window.chrome?'webp':'jpg');
    if (n.clientHeight) {
      img.style.maxWidth = 'auto';
      img.style.width = (containerHeight / 9 * 16) + 'px';
      img.style.marginLeft = Math.round((containerWidth - containerHeight / 9 * 16) / 2) + 'px';
    }
    img.title = 'Shift-click to play directly as HTML5 video\n(sometimes buggy: playback starts only after the entire video is loaded)';
    img.onload = function(e) {
      var img = e.target;
      if (img.naturalWidth <= 120)
        img.onerror(e);
      else {
        if (img.src.indexOf('maxresdefault') < 0)
          img.style.marginTop = ((img.parentNode.clientHeight - img.clientHeight) / 2).toFixed(1) + 'px';
        img.style.setProperty('opacity', '1');
      }
    }
    img.onerror = function(e) {
      var img = e.target;
      if (img.src.indexOf('maxresdefault') > 0)
        img.src = img.src.replace('maxresdefault','hqdefault');
      else if (img.src.indexOf('hqdefault.webp') > 0)
        img.src = img.src.replace('_webp','').replace('.webp','.jpg');
    };

    div.insertAdjacentHTML('beforeend', '\
        <svg class="instant-youtube-play-button"><path fill-rule="evenodd" clip-rule="evenodd" fill="#1F1F1F" class="ytp-large-play-button-svg" d="M84.15,26.4v6.35c0,2.833-0.15,5.967-0.45,9.4c-0.133,1.7-0.267,3.117-0.4,4.25l-0.15,0.95c-0.167,0.767-0.367,1.517-0.6,2.25c-0.667,2.367-1.533,4.083-2.6,5.15c-1.367,1.4-2.967,2.383-4.8,2.95c-0.633,0.2-1.316,0.333-2.05,0.4c-0.767,0.1-1.3,0.167-1.6,0.2c-4.9,0.367-11.283,0.617-19.15,0.75c-2.434,0.034-4.883,0.067-7.35,0.1h-2.95C38.417,59.117,34.5,59.067,30.3,59c-8.433-0.167-14.05-0.383-16.85-0.65c-0.067-0.033-0.667-0.117-1.8-0.25c-0.9-0.133-1.683-0.283-2.35-0.45c-2.066-0.533-3.783-1.5-5.15-2.9c-1.033-1.067-1.9-2.783-2.6-5.15C1.317,48.867,1.133,48.117,1,47.35L0.8,46.4c-0.133-1.133-0.267-2.55-0.4-4.25C0.133,38.717,0,35.583,0,32.75V26.4c0-2.833,0.133-5.95,0.4-9.35l0.4-4.25c0.167-0.966,0.417-2.05,0.75-3.25c0.7-2.333,1.567-4.033,2.6-5.1c1.367-1.434,2.967-2.434,4.8-3c0.633-0.167,1.333-0.3,2.1-0.4c0.4-0.066,0.917-0.133,1.55-0.2c4.9-0.333,11.283-0.567,19.15-0.7C35.65,0.05,39.083,0,42.05,0L45,0.05c2.467,0,4.933,0.034,7.4,0.1c7.833,0.133,14.2,0.367,19.1,0.7c0.3,0.033,0.833,0.1,1.6,0.2c0.733,0.1,1.417,0.233,2.05,0.4c1.833,0.566,3.434,1.566,4.8,3c1.066,1.066,1.933,2.767,2.6,5.1c0.367,1.2,0.617,2.284,0.75,3.25l0.4,4.25C84,20.45,84.15,23.567,84.15,26.4z M33.3,41.4L56,29.6L33.3,17.75V41.4z"></path><polygon fill-rule="evenodd" clip-rule="evenodd" fill="#FFFFFF" points="33.3,41.4 33.3,17.75 56,29.6"></polygon></svg>\
        <a class="instant-youtube-link" href="https://www.youtube.com/watch?v=' + id + '" target="_blank"><b>Watch on Youtube</b></a>\
        <span class="instant-youtube-link" style="margin-top:6em">Watch as HTML5</span>\
    ');

    n.parentNode.insertBefore(div, n);
    n.remove();

    div.addEventListener('click', function clickHandler(e) {
      if (e.target.href)
        return;
      for (var div = e.target; !div.srcEmbed; div = div.parentNode) {}
      var iframeHTML = '<iframe class="instant-youtube-embed" src="' + div.srcEmbed + (div.srcEmbed.indexOf('?') > 0 ? '' : '?') +
          '&autoplay=1' +
          '&autohide=2' +
          '&border=0' +
          '&controls=1' +
          '&fs=1' +
          '&showinfo=1' +
          '&ssl=1' +
          '&theme=dark' +
          '" frameborder="0" allowfullscreen="allowfullscreen" width="' + div.clientWidth + '" height="' + div.clientHeight + '"></iframe>';
      div.removeEventListener('click', clickHandler);
      div.querySelector('svg').outerHTML = '<span class="instant-youtube-loading-button"></span>';
      
      if (!e.shiftKey && e.target.className != 'instant-youtube-link')
        div.insertAdjacentHTML('beforeend', iframeHTML);
      else {
        div.querySelector('span.instant-youtube-link').style.display = 'none';
        GM_xmlhttpRequest({
          method: 'GET',
          url: div.srcEmbed.replace(/\/(embed\/|v[=\/])/, '/watch?v='),
          onload: function(response) {
            var video;
            video = div.appendChild(document.createElement('video'));
            video.controls = true;
            video.autoplay = true;
            video.width = div.clientWidth;
            video.height = div.clientHeight;
            video.className = 'instant-youtube-embed';
            
            var m;
            if (m = response.responseText.match(/ytplayer\.config\s*=\s*(\{.+?\});/)) {
              var cfg = JSON.parse(m[1]), streams = {};
              cfg.args.url_encoded_fmt_stream_map.split(',').forEach(function(stream){
                var params = {}
                stream.split('&').forEach(function(kv){ params[kv.split('=')[0]] = decodeURIComponent(kv.split('=')[1]) });
                streams[params.itag] = params;
              });
              cfg.args.fmt_list.split(',').forEach(function(fmt){
                var itag = fmt.split('/')[0], dimensions = fmt.split('/')[1], stream = streams[itag];
                if (stream) {
                  var source = video.appendChild(document.createElement('source'));
                  source.src = stream.url;
                  source.title = stream.quality + ', ' + dimensions + ', ' + stream.type;
                }
              });
            } else {
              var rx = /url=([^=]+?mime%3Dvideo%252F(?:mp4|webm)[^=]+?)(?:,quality|,itag|.u0026)/g;
              var text = response.responseText.split('url_encoded_fmt_stream_map')[1];
              while (m = rx.exec(text)) {
                video.appendChild(document.createElement('source')).src = decodeURIComponent(decodeURIComponent(m[1]));
              }
            }
            if (video.children.length) {
              if (window.chrome) {
                video.addEventListener('click', function(e) { if (e.target.paused) {e.target.play()} else {e.target.pause()} });
              }
              var title = response.responseText.match(/<title>(.+?)(?:\s*-\s*YouTube)?<\/title>/);
              if (title) {
                var a = div.querySelector('.instant-youtube-link');
                a.innerHTML = '<b>' + title[1] + '</b> - watch on Youtube';
                a.className = 'instant-youtube-link2';
              }
              div.querySelector('img').style.display = 'none';
            } else {
              video.remove();
              div.insertAdjacentHTML('beforeend', iframeHTML);
            }
          }
        });
      } 
    });
  }
  
  return true;
}

function setMutationHandler(baseNode, selector, cb) {
  var ob = new MutationObserver(function(mutations){
    for (var i=0, ml=mutations.length, m; (i<ml) && (m=mutations[i]); i++)
      for (var j=0, nodes=m.addedNodes, nl=nodes.length, n; (j<nl) && (n=nodes[j]); j++)
        if (n.nodeType == 1) 
          if ((n = n.matches(selector) ? [n] : n.querySelectorAll(selector)) && n.length)
            if (!cb(ob, n))
              return;
  });
  ob.observe(baseNode, {subtree:true, childList:true}); 
}