Add YouTube codec check and their settings

browser/internaluserscripts/bundled-scripts/youtube-codec-check.user.js

@@ -0,0 +1,77 @@
+/*
+ * Adapted from enhanced-h264ify's inject_codec_check.js.
+ *
+ * The MIT License (MIT)
+ * Copyright (c) 2019 alextrv
+ * Copyright (c) 2015 erkserkserks
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ */
+
+/* YouTube-only codec selection controls. */
+(function () {
+  "use strict";
+
+  var settings = window.__dactyloidaeYouTubeVideoSettings || {};
+  var originalCanPlayType = HTMLMediaElement.prototype.canPlayType;
+  var originalIsTypeSupported = window.MediaSource &&
+                                window.MediaSource.isTypeSupported;
+
+  function isVideoType(type) {
+    return /(^|\s|;)video\//i.test(type) ||
+           /(^|[; ])codecs\s*=\s*["']?(?:avc|vp0|av0)/i.test(type);
+  }
+
+  function isBlocked(type) {
+    if (!type || !isVideoType(type)) {
+      return false;
+    }
+
+    // AV1 is always blocked, independently of the preferences.
+    if (/av01|av99/i.test(type)) {
+      return true;
+    }
+
+    if (settings.forceH264 && !/avc1|avc3/i.test(type)) {
+      return true;
+    }
+
+    if (settings.hideUnaccelerated &&
+        !settings.vp9HardwareAccelerated && /vp9|vp09/i.test(type)) {
+      return true;
+    }
+
+    if (settings.disable60fps) {
+      var match = /(?:framerate|fps)\s*=\s*([0-9]+(?:\.[0-9]+)?)/i.exec(type);
+      if (match && Number(match[1]) > 30) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  HTMLMediaElement.prototype.canPlayType = function (type) {
+    if (isBlocked(type)) {
+      return "";
+    }
+    return originalCanPlayType.call(this, type);
+  };
+
+  if (window.MediaSource && originalIsTypeSupported) {
+    window.MediaSource.isTypeSupported = function (type) {
+      if (isBlocked(type)) {
+        return false;
+      }
+      return originalIsTypeSupported.call(this, type);
+    };
+  }
+}());