private static IntPtr Filter(EncapsulatableOutputStream stream)
 {
     var encapsulated = EncapsulateDotNetOutputStream(stream);
     try
     {
         return filter_output_stream_through_lzma(encapsulated);
     }
     finally
     {
         release_output_stream(encapsulated);
     }
 }
 public LzmaOutputStream(EncapsulatableOutputStream stream)
     : base(Filter(stream))
 {
 }