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diff --git a/songdbj/javazoom/jl/decoder/Crc16.java b/songdbj/javazoom/jl/decoder/Crc16.java
new file mode 100644
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+++ b/songdbj/javazoom/jl/decoder/Crc16.java
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+/*
+ * 11/19/04 : 1.0 moved to LGPL.
+ * 
+ * 02/12/99 : Java Conversion by E.B , javalayer@javazoom.net
+ *
+ *  @(#) crc.h 1.5, last edit: 6/15/94 16:55:32
+ *  @(#) Copyright (C) 1993, 1994 Tobias Bading (bading@cs.tu-berlin.de)
+ *  @(#) Berlin University of Technology
+ *-----------------------------------------------------------------------
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Library General Public License as published
+ *   by the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program 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 Library General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Library General Public
+ *   License along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *----------------------------------------------------------------------
+ */
+package javazoom.jl.decoder;
+
+/**
+ * 16-Bit CRC checksum
+ */
+public final class Crc16
+{
+  private static        short polynomial=(short)0x8005;
+  private                       short crc;
+
+  /**
+   * Dummy Constructor
+   */
+  public Crc16()
+  { 
+        crc = (short) 0xFFFF;
+  }
+
+  /**
+   * Feed a bitstring to the crc calculation (0 < length <= 32).
+   */
+  public void add_bits (int bitstring, int length)
+  {
+        int bitmask = 1 << (length - 1);
+        do
+         if (((crc & 0x8000) == 0) ^ ((bitstring & bitmask) == 0 ))
+         {
+                crc <<= 1;
+                crc ^= polynomial;
+         }
+         else
+                crc <<= 1;
+        while ((bitmask >>>= 1) != 0);
+  }
+
+  /**
+   * Return the calculated checksum.
+   * Erase it for next calls to add_bits().
+   */
+  public short  checksum()
+  {
+    short sum = crc;
+    crc = (short) 0xFFFF;
+    return sum;
+  }
+}