[DllImport("gstreamer-0.10.dll")]
    private static extern bool gst_pad_query_position(IntPtr raw, ref Format format, out long cur);

    public bool QueryPosition(Gst.Format format, out long current) 
    {
        return gst_pad_query_position(Handle, ref format, out current);
    }

    [DllImport("gstreamer-0.10.dll")]
    private static extern bool gst_pad_query_duration(IntPtr raw, ref Format format, out long duration);

    public bool QueryDuration(Gst.Format format, out long duration) 
    {
        return gst_pad_query_duration(Handle, ref format, out duration);
    }