diff --git a/common/rfb/Decoder.h b/common/rfb/Decoder.h
new file mode 100644
index 0000000..3fdba53
--- /dev/null
+++ b/common/rfb/Decoder.h
@@ -0,0 +1,52 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+#ifndef __RFB_DECODER_H__
+#define __RFB_DECODER_H__
+
+#include <rfb/Rect.h>
+#include <rfb/encodings.h>
+
+namespace rfb {
+  class CMsgReader;
+  class CMsgHandler;
+  class Decoder;
+  typedef Decoder* (*DecoderCreateFnType)(CMsgReader*);
+
+  class Decoder {
+  public:
+    virtual ~Decoder();
+    virtual void readRect(const Rect& r, CMsgHandler* handler)=0;
+
+    static bool supported(unsigned int encoding);
+    static Decoder* createDecoder(unsigned int encoding, CMsgReader* reader);
+    static void registerDecoder(unsigned int encoding,
+                                DecoderCreateFnType createFn);
+  private:
+    static DecoderCreateFnType createFns[encodingMax+1];
+  };
+
+  class DecoderInit {
+    static int count;
+  public:
+    DecoderInit();
+  };
+
+  static DecoderInit decoderInitObj;
+}
+
+#endif