diff -r 000000000000 -r 6474c204b198 content/media/wmf/WMFDecoder.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/media/wmf/WMFDecoder.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,51 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#if !defined(WMFDecoder_h_)
+#define WMFDecoder_h_
+
+#include "MediaDecoder.h"
+
+namespace mozilla {
+
+// Decoder that uses Windows Media Foundation to playback H.264/AAC in MP4
+// and M4A files, and MP3 files if the DirectShow backend is disabled.
+// Playback is strictly limited to only those codecs.
+class WMFDecoder : public MediaDecoder
+{
+public:
+
+  virtual MediaDecoder* Clone() {
+    if (!IsWMFEnabled()) {
+      return nullptr;
+    }
+    return new WMFDecoder();
+  }
+
+  virtual MediaDecoderStateMachine* CreateStateMachine();
+
+  // Loads the DLLs required by Windows Media Foundation. If this returns
+  // failure, you can assume that WMF is not available on the user's system.
+  static nsresult LoadDLLs();
+  static void UnloadDLLs();
+
+  // Returns true if the WMF backend is preffed on, and we're running on a
+  // version of Windows which is likely to support WMF.
+  static bool IsEnabled();
+
+  // Returns true if MP3 decoding is enabled on this system. We block
+  // MP3 playback on Windows 7 SP0, since it's crashy on that platform.
+  static bool IsMP3Supported();
+
+  // Returns the HTMLMediaElement.canPlayType() result for the mime type
+  // and codecs parameter. aCodecs can be empty.
+  static bool CanPlayType(const nsACString& aType,
+                          const nsAString& aCodecs);
+
+};
+
+} // namespace mozilla
+
+#endif